Cynthia de WitForskare
I urval från Stockholms universitets publikationsdatabas
Dietary Intake Contributed the Most to Chlorinated Paraffin Body Burden in a Norwegian Cohort
2022. Bo Yuan (et al.). Environmental Science and Technology 56 (23), 17080-17089Artikel
Determining the major human exposure pathways is a prerequisite for the development of effective management strategies for environmental pollutants such as chlorinated paraffins (CPs). As a first step, the internal and external exposure to CPs were quantified for a well-defined human cohort. CPs in participants’ plasma and diet samples were analyzed in the present study, and previous results on paired air, dust, and hand wipe samples were used for the total exposure assessment. Both one compartment pharmacokinetic modeling and forensic fingerprinting indicate that dietary intake contributed the most to body burden of CPs in this cohort, contributing a median of 60–88% of the total daily intakes. The contribution from dust ingestion and dermal exposure was greater for the intake of long-chain CPs (LCCPs) than short-chain CPs (SCCPs), while the contribution from inhalation was greater for the intake of SCCPs than medium-chain CPs (MCCPs) and LCCPs. Significantly higher concentrations of SCCPs and MCCPs were observed in diets containing butter and eggs, respectively (p < 0.05). Additionally, other exposure sources were correlated to plasma levels of CPs, including residence construction parameters such as the construction year (p < 0.05). This human exposure to CPs is not a local case. From a global perspective, there are major knowledge gaps in biomonitoring and exposure data for CPs from regions other than China and European countries.
Identifying emerging environmental concerns from long-chain chlorinated paraffins towards German ecosystems
2022. Bo Yuan (et al.). Journal of Hazardous Materials 424Artikel
Germany is one of several major European producers of chlorinated paraffins (CPs). This study showed that not only the legacy short-chain products (SCCPs, C10-13), but also the current-use medium- and long-chain products (MCCPs, C14-17; LCCPs, C 17) as well as the very-short-chain impurities (vSCCPs, C<10) are ubiquitous in the 72 samples collected from the coastal, terrestrial, and freshwater ecosystems across the country. The concentrations of LCCPs surpassed those of the other CPs in 40% of the biota samples. Archived bream samples collected downstream of a CP-manufacturing factory showed decreasing temporal trends of (v)SCCPs and relatively constant levels of MCCPs from 1995 to 2019; however, the overall levels of LCCPs have increased by 290%, reflecting the impact of chemical regulation policies on changes in CP production. A visualization algorithm was developed for integrating CP results from various matrices to illustrate spatial tendencies of CP pollution. Higher levels of (v)SCCPs were indicated in the former West Germany region, while MCCP and LCCP concentrations did not seem to differ between former East and West Germany, suggesting relatively equal production and use of these chemicals after the German Reunification. The results provide an early warning signal of environmental concerns from LCCPs on the eve of their booming global production and use.
Influence of climate change on persistent organic pollutants and chemicals of emerging concern in the Arctic: state of knowledge and recommendations for future research
2022. Cynthia A. de Wit, Katrin Vorkamp, Derek Muir. Environmental Science 24 (10), 1530-1543Artikel
Persistent organic pollutants (POPs) have accumulated in polar environments as a result of long-range transport from urban/industrial and agricultural source regions in the mid-latitudes. Climate change has been recognized as a factor capable of influencing POP levels and trends in the Arctic, but little empirical data have been available previously. A growing number of recent studies have now addressed the consequences of climate change for the fate of Arctic contaminants, as reviewed and assessed by the Arctic Monitoring and Assessment Programme (AMAP). For example, correlations between POP temporal trends in air or biota and climate indices, such as the North Atlantic Oscillation Index, have been found. Besides the climate indices, temperature, precipitation and sea-ice were identified as important climate parameters influencing POP levels in the Arctic environment. However, the physical changes are interlinked with complex ecological changes, including new species habitats and predator/prey relationships, resulting in a vast diversity of processes directly or indirectly affecting levels and trends of POPs. The reviews in this themed issue illustrate that the complexity of physical, chemical, and biological processes, and the rapid developments with regard to both climate change and chemical contamination, require greater interdisciplinary scientific exchange and collaboration. While some climate and biological parameters have been linked to POP levels in the Arctic, mechanisms underlying these correlations are usually not understood and need more work. Going forward there is a need for a stronger collaborative approach to understanding these processes due to high uncertainties and the incremental process of increasing knowledge of these chemicals. There is also a need to support and encourage community-based studies and the co-production of knowledge, including the utilization of Indigenous Knowledge, for interpreting trends of POPs in light of climate change.
Influences of climate change on long-term time series of persistent organic pollutants (POPs) in Arctic and Antarctic biota
2022. Katrin Vorkamp (et al.). Environmental Science 24 (10), 1643-1660Artikel
Time series of contaminants in the Arctic are an important instrument to detect emerging issues and to monitor the effectiveness of chemicals regulation, based on the assumption of a direct reflection of changes in primary emissions. Climate change has the potential to influence these time trends, through direct physical and chemical processes and/or changes in ecosystems. This study was part of an assessment of the Arctic Monitoring and Assessment Programme (AMAP), analysing potential links between changes in climate-related physical and biological variables and time trends of persistent organic pollutants (POPs) in Arctic biota, with some additional information from the Antarctic. Several correlative relationships were identified between POP temporal trends in freshwater and marine biota and physical climate parameters such as oscillation indices, sea-ice coverage, temperature and precipitation, although the mechanisms behind these observations remain poorly understood. Biological data indicate changes in the diet and trophic level of some species, especially seabirds and polar bears, with consequences for their POP exposure. Studies from the Antarctic highlight increased POP availability after iceberg calving. Including physical and/or biological parameters in the POP time trend analysis has led to small deviations in some declining trends, but did generally not change the overall direction of the trend. In addition, regional and temporary perturbations occurred. Effects on POP time trends appear to have been more pronounced in recent years and to show time lags, suggesting that climate-related effects on the long time series might be gaining importance.
Outside the Safe Operating Space of the Planetary Boundary for Novel Entities
2022. Linn Persson (et al.). Environmental Science and Technology 56 (3), 1510-1521Artikel
We submit that the safe operating space of the planetary boundary of novel entities is exceeded since annual production and releases are increasing at a pace that outstrips the global capacity for assessment and monitoring. The novel entities boundary in the planetary boundaries framework refers to entities that are novel in a geological sense and that could have large-scale impacts that threaten the integrity of Earth system processes. We review the scientific literature relevant to quantifying the boundary for novel entities and highlight plastic pollution as a particular aspect of high concern. An impact pathway from production of novel entities to impacts on Earth system processes is presented. We define and apply three criteria for assessment of the suitability of control variables for the boundary: feasibility, relevance, and comprehensiveness. We propose several complementary control variables to capture the complexity of this boundary, while acknowledging major data limitations. We conclude that humanity is currently operating outside the planetary boundary based on the weight-of-evidence for several of these control variables. The increasing rate of production and releases of larger volumes and higher numbers of novel entities with diverse risk potentials exceed societies’ ability to conduct safety related assessments and monitoring. We recommend taking urgent action to reduce the harm associated with exceeding the boundary by reducing the production and releases of novel entities, noting that even so, the persistence of many novel entities and/or their associated effects will continue to pose a threat.
Relationships between gene transcription and contaminant concentrations in Baltic ringed seals: A comparison between tissue matrices
2022. Joy Ometere Boyi (et al.). Aquatic Toxicology 242Artikel
Ringed seals (Pusa hispida) are slowly recovering in the eastern and northern parts of the Baltic Sea after years of hunting pressure and contaminant exposure. Still, consequences of anthropogenic activities such as contaminant exposure and increasing temperatures are stressors that continue to have deleterious effects on their habitat and health. Transcription profiles of seven health-related genes involved in xenobiotic metabolism, endocrine disruption and stress were evaluated in blood, blubber, and liver of Baltic ringed seals in a multi-tissue approach. Selected persistent organic pollutants and total mercury concentrations were measured in blubber and liver, and muscle and liver of these animals, respectively. Concentrations of contaminants varied across tissues on a lipid weight basis but not with sex. mRNA transcript levels for all seven target genes did not vary between sexes or age classes. Transcript levels of thyroid hormone receptor alpha (TR alpha), retinoic acid receptor alpha (RAR alpha) and heat shock protein 70 (HSP70) correlated with levels of persistent organic pollutants. TR alpha transcript levels also correlated positively with mercury concentrations in the liver. Of the three tissues assessed in this multi-tissue approach, blubber showed highest transcription levels of aryl hydrocarbon receptor nuclear translocator (ARNT), thyroid stimulating hormone receptor beta (TSH beta), oestrogen receptor alpha (ESR1) and peroxisome proliferator activated receptor alpha (PPAR alpha). The wide range of genes expressed highlights the value of minimally invasive sampling (e.g. biopsies) for assessing health endpoints in free-ranging marine wildlife and the importance of identifying optimal matrices for targeted gene expression studies. This gene transcript profile study has provided baseline information on transcript levels of biomarkers for early on-set health effects in ringed seals and will be a useful guide to assess the impacts of environmental change in Baltic pinnipeds for conservation and management.
Response to Comment on "outside the Safe Operating Space of the Planetary Boundary for Novel Entities"
2022. L. Persson (et al.). Environmental Science and Technology 56 (10), 6788-6789Artikel
Temporal Trends and Age-Dependent Sex Differences in Chlorinated Paraffin Accumulation in Moose
2022. Bo Yuan, Cynthia A. de Wit. Environmental Science and Technology Letters 9 (12), 1044-1049Artikel
Previous studies have found relatively high chlorinated paraffin (CP) concentrations in moose (Alces alces) compared with other wildlife from Scandinavia. To explore CP accumulation behaviors in this long-lived terrestrial mammal, temporal trends of muscle concentrations of CPs were first measured in samples collected over the past 40 years from moose calves from Grimsö, Sweden. The four CP classes, i.e., very-short-chain, short-chain, medium-chain, and long-chain (LCCPs) classes, showed similar temporal trends, with increasing concentrations from 1982 to the 1990s, relatively high levels in two time periods around 1993 and 2008, and decreasing concentrations after 2012. A concentration plateau period was identified, and moose samples of both sexes and different ages from the median year (1993) of the concentration plateau period were selected for further analysis. CP levels increased exponentially with age in the male moose, while CP levels were found to exponentially decrease with age in females. LCCPs showed the slowest decreasing tendency with age in females compared with the other three classes, resulting in a general increase of the LCCP proportions with age. The sex-biased accumulation of CPs indicates additional stresses from these POP-like chemicals toward males of the largest and one of the most widespread terrestrial mammals in northern hemisphere forests.
Understanding and addressing the planetary crisis of chemicals and plastics
2022. Bethanie Carney Almroth (et al.). One Earth 5 (10), 1070-1074Artikel
Planetary functions are destabilized by the releases of large quantities and numbers of anthropogenic chemicals, which go beyond planetary boundaries and threaten the safe operating space for humanity. Here, we call for urgent action to mitigate these threats and identify opportunities for intervention along the impact pathway of anthropogenic chemicals, including plastics.
Can determination of extractable organofluorine (EOF) be standardized? First interlaboratory comparisons of EOF and fluorine mass balance in sludge and water matrices
2021. Anna Kärrman (et al.). Environmental Science (10)Artikel
The high proportion of unidentified extractable organofluorine (EOF) observed globally in humans and the environment indicates widespread occurrence of unknown per- and polyfluoroalkyl substances (PFAS). However, efforts to standardize or assess the reproducibility of EOF methods are currently lacking. Here we present the first EOF interlaboratory comparison in water and sludge. Three participants (four organizations) analyzed unfortified and PFAS-fortified ultrapure water, two unfortified groundwater samples, unfortified wastewater treatment plant effluent and sludge, and an unfortified groundwater extract. Participants adopted common sample handling strategies and target lists for EOF mass balance but used in-house combustion ion-chromatography (CIC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods. EOF accuracy ranged from 85-101% and 76-109% for the 60 and 334 ng L-1 fluorine (F) - fortified water samples, respectively, with between-laboratory variation of 9-19%, and within-laboratory variation of 3-27%. In unfortified sludge and aqueous samples, between-laboratory variation ranged from 21-37%. The contribution from sum concentrations of 16 individual PFAS ( n-ary sumation PFAS-16) to EOF ranged from 2.2-60% but extended analysis showed that other targets were prevalent, in particular ultra-short-chain perfluoroalkyl acids (e.g. trifluoroacetic acid) in aqueous samples and perfluoroalkyl acid-precursors (e.g. polyfluoroalkyl phosphate diesters) in sludge. The EOF-CIC method demonstrated promising accuracy, robustness and reporting limits but poor extraction efficiency was observed for some targets (e.g. trifluoroacetic acid).
Human Exposure to Chlorinated Paraffins via Inhalation and Dust Ingestion in a Norwegian Cohort
2021. Bo Yuan (et al.). Environmental Science and Technology 55 (2), 1145-1154Artikel
Very-short- (vSCCPs, C6-9), short- (SCCPs, C10-13), medium-(MCCPs, C14-17), and long-chain chlorinated paraffins (LCCPs, C->17) were analyzed in indoor air and dust collected from the living rooms and personal 24 h air of 61 adults from a Norwegian cohort. Relatively volatile CPs, i.e., vSCCPs and SCCPs, showed a greater tendency to partition from settled indoor dust to paired stationary indoor air from the same living rooms than MCCPs and LCCPs, with median logarithmic dust-air partition ratios of 1.3, 2.9, 4.1, and 5.4, respectively. Using the stationary indoor air and settled indoor dust concentrations, the combined median daily exposures to vSCCPs, SCCPs, MCCPs, and LCCPs were estimated to be 0.074, 2.7, 0.93, and 0.095 ng/kg bw/d, respectively. Inhalation was the predominant exposure pathway for vSCCPs (median 99%) and SCCPs (59%), while dust ingestion was the predominant exposure pathway for MCCPs (75%) and LCCPs (95%). The estimated inhalation exposure to total CPs was similar to 5 times higher when the personal 24 h air results were used rather than the corresponding stationary indoor air results in 13 paired samples, indicating that exposure situations other than living rooms contributed significantly to the overall personal exposure. The 95th percentile exposure for CPs did not exceed the reference dose.
Long-Chain Chlorinated Paraffins Have Reached the Arctic
2021. Bo Yuan (et al.). Environmental Science and Technology Letters 8 (9), 753-759Artikel
Chlorinated paraffins (CPs) were analyzed in marine wildlife from Greenland, Iceland, and the Swedish west coast. CPs up to C-29 were detected in the samples from the Arctic, indicating long-range transport of an industrial chemical group with a 2-million-ton annual production volume. CP concentrations were generally higher in biota from the Swedish west coast. The Sweden/Arctic concentration ratios for very-short-chain (vSCCPs, C-<10), short-chain (SCCPs, C10-13), medium-chain (MCCPs, C14-17), and long-chain CPs (LCCPs, C->17) in cetacean and bivalve species were in the range of 3.6-150, 5-29, 3-11, and 11-450, respectively. For the first time, fetal accumulation of four CP classes was found, whereby concentrations were 3.4 to 4.5 times lower in the fetus relative to the pregnant female minke whale. Cetacean blubber contained a higher proportion of higher chlorinated CPs compared to muscle tissue, while muscle contained higher lipid-normalized concentrations of longer chain CPs than blubber tissue. LCCPs predominated (52% of total CPs) in the muscle of a killer whale from Swedish waters, which is the first report where concentrations of LCCPs surpassed those of other CPs in marine mammals. This study shows that, like other CP classes, LCCPs are Arctic contaminants that may adversely affect biota in this remote region.
Persistent organic pollutants (POPs) in fish species from different lakes of the lesser Himalayan region (LHR), Pakistan: The influence of proximal sources in distribution of POPs
2021. Rahat Riaz, Cynthia A. de Wit, Riffat Naseem Malik. Science of the Total Environment 760Artikel
Fish dwelling in remote mountain water systems are sensitive to long term exposure of POPs and can be used as an important bioindicator of POPs pollution in fragile mountain ecosystems. Current study aimed to investigate the concentrations and patterns of organic pollutants in fish tissues from different lakes of the Lesser Himalayan Region (LHR). OCPs, PCBs, PBDEs were analyzed in four common edible fish species of the LHR: Oncorhynchus mykiss, Labeo rohita, Hypophthalmichthys molitrix and Orechromis aureus. The fish were collected from lakes with different types of catchment areas (glacial, non-glacial mountain region and urban region) and extent of anthropogenic influence. The levels OCPs, PCBs and PBDEs analyzed in the selected fish species were in range of 0.21-587, 6.4-138 and 1.2-14 ng g(-1) lw, respectively. The SDDTs, higher chlorinated PCBs, tetra- and pentaBDEs were more prevalent in urban and remote lakes whereas pp'-DDE, lower chlorinated PCBs and BDE-47 and -99 were predominant in fish species from glacial lakes. SDDTs, SPCBs and SPBDEs showed statistically significant differences (p < 0.05) among species, trophic guilds (carnivore, herbivore and omnivore) and feeding regimes (surface, bottom and column feeder) and SHCH showed a significant difference only among trophic guilds. The stable isotope values of delta N-15 and delta C-13 differed significantly among species for SSHCH, SPCBs, SPBDEs (p < 0.05) and SDDT (p < 0.01). The range of delta C-13 values (-34 to-19%) indicated the importance of littoral and pelagic sources of dietary carbon. Trophic position and dietary proxieswere identified as important variables for explaining the variability of the studied compounds. Kohonen self-organizing maps (SOM) showed that in addition to trophic position and other physiological characteristics of fish, that the type of lakes and proximal sources of POPswere the most important predictors for distribution of organic contaminants in fish samples from LHR.
Semi-Volatile Organic Compounds in Car Dust: A Pilot Study in Jeddah, Saudi Arabia
2021. Nadeem Ali (et al.). International Journal of Environmental Research and Public Health 18 (9)Artikel
People may spend a significant amount of their daily time in cars and thus be exposed to chemicals present in car dust. Various chemicals are emitted from during car use, contaminating the car dust. In this study, we compiled published and unpublished data on the occurrence of phthalates, flame retardants (FRs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) in Saudi car dust. Phthalates, a class of chemical commonly used as plasticizers in different car parts, were the major pollutants found in car dust, with a median value of n-ary sumation phthalates 1,279,000 ng/g. Among other chemicals, organophosphate flame retardants (OPFRs) were found to be between 1500-90,500 ng/g, which indicates their use as alternative FRs in the car industry. The daily exposure to Saudi drivers (regular and taxi drivers) was below the respective reference dose (RfD) values of the individual chemicals. However, the estimated incremental lifetime cancer risk (ILCR) values due to chronic exposure to these chemicals was >1 x 10(-5) for taxi drivers for phthalates and PAHs, indicating that the long-term exposure to these chemicals is a cause of concern for drivers who spend considerable time in cars. The study has some limitations, due to the small number of samples, lack of updated RfD values, and missing cancer slope factors for many studied chemicals. Despite these limitations, this study indicates the possible range of exposure to drivers from chemicals in car dust and warrants further extensive studies to confirm these patterns.
Soil-air partitioning of semivolatile organic compounds in the Lesser Himalaya region: Influence of soil organic matter, atmospheric transport processes and secondary emissions
2021. Rahat Riaz, Riffat Naseem Malik, Cynthia A. de Wit. Environmental Pollution 291Artikel
After decades of imposed regulations about reducing the primary emissions of persistent organic pollutants (POPs), these pollutants are still present in the environment. Soils are important repositories of such persistent semivolatile organic contaminants (SVOCs), and it is assumed that SVOCs sequestered in these reservoirs are being re-mobilized due to anthropogenic influence. In this study, concentrations of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) in soil and air, their fugacities, fluxes and the soil-air partition coefficient (KSA) were determined for three different land cover types (glacial, remote/mountainous and urban) of the Lesser Himalayan Region (LHR). The concentrations of OCPs, PCBs and PBDEs in soils and air ranged between 0.01 and 2.8, 0.81-4.8, 0.089-0.75 ng g(-1); 0.2-106, 0.027-182, and 0.011-7.26 pg m- 3, respectively. The levels of SVOCs in the soil were correlated with soil organic matter (SOM) indicating that SOM is a substrate for the organic pollutants in soils. The Clausius-Clapeyron plots between ln P and inverse of temperature (1000/T) suggested that long range atmospheric transport was the major input source of PBDEs and higher chlorinated PCBs over the LHR. The uneven and wide distribution of local sources in LHR and up-slope enrichment of SVOCs explained the spatial variability and altitudinal patterns. The soils near mountain and urban lakes act as local sinks of SVOCs such as beta-HCH, ppGREEK TONOS-DDT, CB-28,-118,-153, BDE-47,-99, and-154, with soil-air exchange fluxes tending more toward deposition. However, the soils near glacial lakes acted as local sources of more volatile congeners of alpha-HCH, gamma-HCH, op'-DDT, pp'-DDE and lower to medium chlorinated PCBs such as CB-18,-28,-53,-42 and BDE-47,-99, with soil-air exchange tending more toward volatilization flux.
The Baltic Sea: An ecosystem with multiple stressors
2021. R. Dietz (et al.). Environment International 147Artikel
This introductory chapter to our Environment International VSI does not need an abstract and therefore we just include our recommendations below in order to proceed with the resubmission. Future work should examine waterbirds as food web sentinels of multiple stressors as well as Baltic Sea food web dynamics of hazardous substances and how climate change may modify it. Also, future work should aim at further extending the new frameworks developed within BALTHEALTH for energy and contaminant transfer at the population level (Des forges et al., 2018, Cervin et al., 2020/this issue Silva et al., 2020/this issue) and their long term effects on Baltic Sea top predators, such as harbour porpoises, grey seals ringed seals, and white-tailed eagles. Likewise, the risk evaluation conducted for PCB in connection with mercury on Arctic wildlife (Dietz et al., 2019, not a BONUS BALTHEALTH product) could be planned for Baltic Sea molluscs, fish, bird and marine mammals in the future. Finally, future efforts could include stressors not covered by the BONUS BALTHEALTH project, such as food web fluxes, overexploitation, bycatches, eutrophication and underwater noise.
The effect of reduction measures on concentrations of hazardous semivolatile organic compounds in indoor air and dust of Swedish preschools
2021. Sarka Langer (et al.). Indoor Air 31 (5), 1673-1682Artikel
Young children spend a substantial part of their waking time in preschools. It is therefore important to reduce the load of hazardous semivolatile organic compounds (SVOCs) in the preschools' indoor environment. The presence and levels of five SVOC groups were evaluated (1) in a newly built preschool, (2) before and after renovation of a preschool, and (3) in a preschool where SVOC-containing articles were removed. The new building and the renovation were performed using construction materials that were approved with respect to content of restricted chemicals. SVOC substance groups were measured in indoor air and settled dust and included phthalates and alternative plasticizers, organophosphate esters (OPEs), brominated flame retardants, and bisphenols. The most abundant substance groups in both indoor air and dust were phthalates and alternative plasticizers and OPEs. SVOC concentrations were lower or of the same order of magnitude as those reported in comparable studies. The relative Cumulative Hazard Quotient (HQ(cum)) was used to assess the effects of the different reduction measures on children's SVOC exposure from indoor air and dust in the preschools. HQ(cum) values were low (1.0-6.1%) in all three preschools and decreased further after renovation and article substitution. The SVOCs concentrations decreased significantly more in the preschool renovated with the approved building materials than in the preschool where the SVOC-containing articles were removed.
Chlorinated Paraffins in Two Snake Species from the Yangtze River Delta: Tissue Distribution and Biomagnification
2020. Xinyu Du (et al.). Environmental Science and Technology 54 (5), 2753-2762Artikel
Very-short, short-, medium-, and long-chain chlorinated paraffins (vSCCPs, SCCPs, MCCPs, and LCCPs, respectively) were analyzed in different tissues of the terrestrial short-tailed mamushi (Gloydius brevicaudus) and the semi-aquatic red-backed rat snake (Elaphe rufodorsata) from the Yangtze River Delta, China. The total CP concentrations in liver, muscle, and adipose tissues in the two snake species were in the range of 2500-24 000, 4900-48 000, and 12-630 ng/g lw, respectively. Tissue burdens indicated that vSCCPs (C6-9) and SCCPs (C10-3) preferentially distributed to snake liver, while adipose was an important storage site and sink of MCCPs (C14-17) and LCCPs (C->18). On a lipid weight basis, vSCCPs and SCCPs were found in highest concentrations in red-backed rat snake liver and MCCPs and LCCPs in muscle, whereas for short-tailed mamushi, all CP groups were predominant in muscle, probably reflecting ecosystem/food web differences. Moreover, vSCCPs, SCCPs, MCCPs, and LCCPs were found to be biomagnified from black-spotted frogs to red-backed rat snakes with mean (maximum) biomagnification factors of 2.2 (3.4), 1.9 (3.7), 1.8 (2.8), and 1.7 (4.5), respectively. This is the first field study of biomagnification potential involving vSCCPs and LCCPs and highlights the need to include all CPs in studies.
Complex Mixtures of Chlorinated Paraffins Found in Hand Wipes of a Norwegian Cohort
2020. Bo Yuan (et al.). Environmental Science and Technology Letters 7 (3), 198-205Artikel
Up to 18000 ng of total chlorinated paraffins (CPs) was found in hand wipes of individual adult participants in a Norwegian cohort study (n = 60), with a geometric mean (SD) value of 870 (2700) ng. The CPs covered a wide range of alkane chain lengths from C-7 to C-48 with variable chlorine substitution. Complex mixtures of very-short-chain (vSCCPs, C-<10), short-chain (SCCPs, C10-13), medium-chain (MCCPs, C14-17), and long-chain (LCCPs, C->17) CPs were found, contributing on average 0.3%, 20%, 58%, and 22%, respectively, of the total CPs. Significant positive correlations were found between CP levels and factors related to the indoor environment and product use, including living in a house/apartment built before the ban of SCCPs, having a sofa, the number of TVs in the home, and owning a car, which mirrors CP usage as flame retardants and/or plasticizers in consumer products. Compared to previous studies of other organic contaminants in hand wipe samples from the same cohort, CPs were the most abundant flame retardants. This is the first report of CPs in hand wipes, and dermal exposure based on these data suggested that hand contact could be an important human exposure pathway for LCCPs.
Organohalogen compounds of emerging concern in Baltic Sea biota: Levels, biomagnification potential and comparisons with legacy contaminants
2020. Cynthia A. de Wit (et al.). Environment International 144Artikel
While new chemicals have replaced major toxic legacy contaminants such as polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT), knowledge of their current levels and biomagnification potential in Baltic Sea biota is lacking. Therefore, a suite of chemicals of emerging concern, including organophosphate esters (OPEs), short-chain, medium-chain and long-chain chlorinated paraffins (SCCPs, MCCPs, LCCPs), halogenated flame retardants (HFRs), and per- and polyfluoroalkyl substances (PFAS), were analysed in blue mussel (Mytilus edulis), viviparous eelpout (Zoarces viviparus), Atlantic herring (Clupea harengus), grey seal (Halichoerus grypus), harbor seal (Phoca vitulina), harbor porpoise (Phocoena phocoena), common eider (Somateria mollissima), common guillemot (Uria aalge) and white-tailed eagle (Haliaeetus albicilla) from the Baltic Proper, sampled between 2006 and 2016. Results were benchmarked with existing data for legacy contaminants. The mean concentrations for Sigma OPEs ranged from 57 to 550 ng g(-1) lipid weight (lw), for Sigma CPs from 110 to 640 ng g(-1) lw for Sigma HFRs from 0.42 to 80 ng g(-1) lw, and for Sigma PFAS from 1.1 to 450 ng g(-1) wet weight. Perfluoro-4-ethyl-cyclohexanesulfonate (PFECHS) was detected in most species. Levels of OPEs, CPs and HFRs were generally similar or higher than those of polybrominated diphenyl ethers (PBDEs) and/or hexabromocyclododecane (HBCDD). OPE, CP and HFR concentrations were also similar to PCBs and DDTs in blue mussel, viviparous eelpout and Atlantic herring. In marine mammals and birds, PCB and DDT concentrations remained orders of magnitude higher than those of OPEs, CPs, HFRs and PFAS. Predator-prey ratios for individual OPEs (0.28-3.9) and CPs (0.40-5.0) were similar or somewhat lower than those seen for BDE-47 (5.0-29) and HBCDD (2.4-13). Ratios for individual HFRs (0.010-37) and PFAS (0.15-47) were, however, of the same order of magnitude as seen for p,p'-DDE (4.7-66) and CB-153 (31-190), indicating biomagnification potential for many of the emerging contaminants. Lack of toxicity data, including for complex mixtures, makes it difficult to assess the risks emerging contaminants pose. Their occurence and biomagnification potential should trigger risk management measures, particularly for MCCPs, HFRs and PFAS.
Spatio-temporal variation of metals and organic contaminants in bank voles (Myodes glareolus)
2020. Frauke Ecke (et al.). Science of the Total Environment 713Artikel
Environmental contamination with metals and organic compounds is of increasing concern for ecosystem and human health. Still, our knowledge about spatial distribution, temporal changes and ecotoxicological fate of metals and organic contaminants in wildlife is limited. We studied concentrations of 69 elements and 50 organic compounds in 300 bank voles (Myodes glareolus), Europe's most common mammal, sampled in spring and autumn 2017-2018 in five monitoring areas, representing three biogeographic regions. In addition, we compared measured concentrations with previous results from bank voles sampled within the same areas in 1995-1997 and 2001. In general, our results show regional differences, but no consistent patterns among contaminants and study areas. The exception was for the lowest concentrations of organic contaminants (e.g. perfluorooctane sulfonate, PFOS), which were generally found in the northern Swedish mountain area Concentrations of metals and organic contaminants in adults varied seasonally with most organic contaminants being higher in spring; likely induced by diet shifts but potentially also related to age differences. In addition, metal concentrations varied between organs (liver vs. kidney), age classes (juveniles vs. adults; generally higher in adults) as well as between males and females. Concentrations of chromium and nickel in kidney and liver in the northernmost mountain area were lower in 2017-2018 than in 1995-1997 and in three of four areas, lead concentrations were lower in 2017-2018 than in 2001. Current metal concentrations (except mercury) are not expected to negatively affect the voles. Concentrations of hexachlorobenzene displayed highest concentrations in 2001 in the mountains, while it was close to detection limit in 2017-2018. Likewise, PFOS concentrations decreased in the mountains and in south-central lowland forests between 2001 and 2017-2018. Our results suggest that season, age class and sex need to be considered when designing and interpreting results from monitoring programs targeting inorganic and organic contaminants in wildlife.
Accumulation of Short-, Medium-, and Long-Chain Chlorinated Paraffins in Marine and Terrestrial Animals from Scandinavia
2019. Bo Yuan (et al.). Environmental Science and Technology 53 (7), 3526-3537Artikel
Short-, medium-, and long-chain chlorinated paraffins (SCCPs, MCCPs, and LCCPs) have a wide range of physical-chemical properties, indicating their varying bioaccumulation tendencies in marine and terrestrial ecosystems. However, there are few empirical data to reveal such bioaccumulation tendencies. In this study, we analyzed SCCPs, MCCPs, and LCCPs in samples from 18 species at both low and high trophic levels of marine and terrestrial ecosystems from the Scandinavian region collected during the past decade. These included fish, seabirds, marine mammals, and terrestrial birds and mammals. SCCPs, MCCPs, and LCCPs were present in all the species, with concentrations ranging from 26-1500, 30-1600, 6.0-1200 ng/g lipid, respectively. Although MCCPs and SCCPs predominated in species, many terrestrial species had generally higher concentrations of LCCPs than marine species. Terrestrial raptors in particular accumulated higher concentrations of LCCPs, including C-24/25-which are predominant among very-long-chain components. LCCP concentrations were highest and predominated (55% of total CPs) in peregrine falcons in this study, which is the first report where concentrations of LCCPs surpass those of SCCPs and MCCPs in wildlife. The results also indicate biomagnification of SCCPs, MCCPs, and LCCPs in both marine and terrestrial food chains, but in-depth studies of specific food webs are needed.
Mass balance study of brominated flame retardants in female captive peregrine falcons
2019. Cynthia A. de Wit (et al.). Environmental Science 21 (7), 1115-1131Artikel
Little is known about brominated flame retardant (BFR) dynamics in birds, especially large molecules such as decabromodiphenyl ether (BDE-209). In particular, bioaccumulation from food and transfer dynamics to eggs are poorly understood. Therefore, an input-output mass balance study of tri-decaBDEs, DBDPE and HBCDD was performed in three female peregrine falcons from a captive breeding program by analyzing their naturally contaminated food (quail, chicken (cockerels)), plasma, feces and eggs. Predominant BFRs in cockerels and quail were BDE-209 and DBDPE, as well as HBCDD in quail. The predominant BFRs found in falcon plasma were BDE-209, -153 and -183, in eggs, HBCDD, BDE-209 and -153 and in feces, BDE-209. Mean absorption efficiencies (AE) for the tetra-octabrominated BDEs ranged from 84-100% and 70% for HBCDD. The AEs for BDE-206, -207, -208 and -209 varied due to the large variability seen for feces fluxes. All egg/plasma ratios for BDEs were similar and greater than one (range 1.1-2.7), including for BDE-209, indicating efficient transfer from females to the eggs. Excretion via egg-laying was approximately 6.0-29% of the initial, pre-breeding body burden of individual penta-decaBDE congeners, (15-45% for BDE-206). HBCDD was not detected in plasma but was found in eggs, also indicating efficient transfer and excretion via eggs. Input fluxes from food exceeded the output fluxes (feces, eggs) indicating considerable metabolism for tetra-octaBDEs, possibly also for the nona-decaBDEs and HBCDD. Bioaccumulation factors calculated from lipid weight concentrations in plasma and food (BAF(p)) were highest for BDE-208 (31), -153 (23), -209 (19) and -207 (16) and from eggs and food (BAF(e)), were highest for HBCDD (140), BDE-153 (41), -208 (42), BDE-207 (24) and BDE-209 (21). BAF(e) and BAF(p) values were below 10 for BDE-47, -99 and -100. For one falcon, egg results were available from three different years and estimated half-lives were 65 d (BDE-99), 624 d (BDE-153), 31 d (BDE-154), 349 d (BDE-183), 77 d (BDE-196) and 89 d (BDE-197).
Occurrence of legacy and alternative plasticizers in indoor dust from various EU countries and implications for human exposure via dust ingestion and dermal absorption
2019. Christina Christia (et al.). Environmental Research 171, 204-212Artikel
Plasticizers are a category of chemicals extensively used in consumer products and, consequently, their presence is ubiquitous in the indoor environment. In the present study, an analytical method has been developed for the quantification of plasticizers (7 legacy phthalate esters (LPEs) and 14 alternative plasticizers (APs)) in indoor floor dust based on ultrasonic and vortex extraction, Florisil fractionation and GC-(EI)-MS analysis. Dust samples (n = 54) were collected from homes, offices, and daycare centers from different EU countries (Belgium, the Netherlands, Ireland and Sweden). Method LOQs ranged from 0.2 to 5 mu g/g. Tri-n-hexyl trimellitate (THTM) was not detected in any sample, whereas dimethyl phthalate (DMP), diphenyl phthalate and acetyl triethyl citrate (ATEC) were detected only in 6, 2 and 1 out of 54 samples, respectively. The highest concentrations of plasticizers were measured in Swedish offices, at a mean concentration of total plasticizers of 1800 mu g/g, followed by Swedish daycare centers at 1200 and 670 mu g/g for winter and spring sampling, respectively. Generally, the contribution of APs was slightly higher than for LPEs for all indoor environments (mean contribution 60% and 40%, respectively based on contributions per indoor environment). For the APs, main contributors were DINP in Belgian homes (28%), Swedish offices (60%), Swedish daycare centers (48%), and Dutch offices (31%) and DEHT in Belgian (28%), Irish (40%) and Dutch homes (37%) of total APs. The predominant LPE was bis-2-ethylhexyl-phthalate (DEHP) with a mean contribution varying from 60% to 85% of total LPEs. Human exposure was evaluated for dust ingestion and dermal absorption using hazard quotients (HQs) of plasticizers (ratio between average daily doses and the reference dose). None of the HQs of plasticizers exceeded 1, meaning that the risk for adverse human health effects from these plasticizers via dust ingestion and dermal absorption is unlikely.
Organohalogenated Flame Retardants and Organophosphate Esters in Office Air and Dust from Sweden
2019. Fang Tao, Ulla Sellström, Cynthia A. de Wit. Environmental Science and Technology 53 (4), 2124-2133Artikel
A wide range of organohalogenated flame retardants (HFRs) and organophosphate esters (OPEs) were measured in air and floor dust from 10 offices in Stockholm, Sweden. Concentrations of Sigma 18 emerging HFRs, Sigma 21 legacy HFRs and Sigma 11 OPEs from the offices were found to be 420, 510, and 1600000 ng/g, respectively, in floor dust and 400, 15, and 160 000 pg/m(3) respectively in active air samples. All targeted compounds were detected in dust except 2,3,5,6-tetrabromo-p-xylene (pTBX) indicating widespread application of a broad range of FRs in the Swedish offices while only 54% of targeted compounds were detected in indoor air. Estimated Sigma OPE exposure in Swedish offices is 3-4 orders of magnitude higher than for Sigma emerging HFRs and Sigma legacy HFRs via all three different exposure routes in our study. Adult's estimated intakes of emerging and legacy HFRs and OPEs from office air and dust during working hours (30% of a day) are some orders of magnitude lower than the corresponding reference doses (RfD). However, in worst case exposure scenarios (maximum concentrations and high dust intake), the intake of tris(2-butoxyethyl) phosphate (TBOEP) was one-third of its RfD, which may be of potential concern if exposure is as high in other microenvironments.
Serum concentrations of legacy and emerging halogenated flame retardants in a Norwegian cohort: Relationship to external exposure
2019. Joo Hui Tay (et al.). Environmental Research 178Artikel
Sixty-one serum samples from a Norwegian cohort were analyzed for 43 emerging and legacy halogenated flame retardants (HFRs). BDE-47, -153, -197 and -209 were detected in > 56% of the samples with median concentrations of 0.23, 1.0, 0.64 and 1.5 ng/g lipid, respectively. BDE-49, -85, -99, -100, -154, -206, -207, 208 as well as HBB, syn- and anti-DDC-CO, OBTMPI, DBDPE, alpha-HBCDD and TBBPA were also detected in some serum samples (detection frequencies of 2-36%). Other tri-octaBDEs, TBP-AE, alpha- and beta-DBE-DBCH, BATE, pTBX, alpha beta-TBCO, PBBz, TBCT, PBT, PBEB, DPTE, EH-TBB, BTBPE, BEH-TEBP, HCDBCO, beta- and gamma-HBCDD were below the limits of detection (mLOD). Concentrations of individual BDE congeners detected in this study were within the range from previous European studies. Positive correlations were seen between concentrations of BDE-47 in dust and BDE-153 in serum, between BDE-153 in dust and BDE-153 in serum, and between BDE-153 masses in handwipes and BDE-47 concentrations in serum (Spearman's rank, 0.29 < r < 0.43). Associations between the number of phones/mobiles, numbers of electronic equipment per person in the home and the consumption of specific food categories (such as soups/spices/sauces and alcoholic beverages) with BDE-47 and -153 serum levels were confirmed by multivariate linear regression analyses. The measured median serum level of BDE-47 was slightly over-predicted by a factor of 5.5 whereas other BDE congeners were under-predicted by factors of 13-6000 when compared to serum concentrations predicted from external exposure media (inhalation, dermal uptake, dietary intake from duplicate diet and dust ingestion) using a simple one compartment pharmacokinetic (PK) model. BDE-153 was not detected and BDE-197 not analyzed in food so no dietary intake assessments for these could be made, which may partially explain the discrepancies between their measured and predicted serum concentrations. Overall, our results suggest that exposure via diet is the most important exposure pathway for BDE-47 and -209, with diet being responsible for more than 96% of the total daily intake of these two BDEs in the Norwegian cohort.
Shorter than short-chain: Very short-chain chlorinated paraffins (vSCCPs) found in wildlife from the Yangtze River Delta
2019. Yihui Zhou (et al.). Environment International 130Artikel
Very short-chain chlorinated paraffins (vSCCPs, C6-9) occurred in 94% of wildlife samples from the Yangtze River Delta (YRD), China, with CnClm comparable to that of a local CP product, CP-52. Therefore, we determined the content of vSCCPs in CP-52 using a mathematical deconvolution technique. Then with CP-52 and several other reference standards, vSCCPs together with short-, medium-, and long-chain CPs were quantified in 21 wildlife species from an artificial wetland ecosystem and a freshwater ecosystem in the YRD. Concentrations of vSCCPs ranged from 2.6 to 8400 ng/g lipid. These concentrations were 1.2-380 fold lower than SCCPs, but were significantly correlated with those of SCCPs. vSCCP concentrations were comparable to or higher than reported for brominated flame retardants in the same samples. Bioaccumulation tendency of vSCCPs was identified in two benthic species, indicating congener-specific accumulation of vSCCPs in the environment.
Assessment of dermal exposure to halogenated flame retardants: Comparison using direct measurements from hand wipes with an indirect estimation from settled dust concentrations
2018. Joo Hui Tay (et al.). Environment International 115, 285-294Artikel
There are few studies estimating dermal exposure to halogenated flame retardants in adults. To fill this gap, sixty-one hand wipe samples were collected from a Norwegian adult cohort using gauze pads immersed in isopropanol. BDE-47, BDE-209, bis(2‑ethyl‑hexyl)‑3,4,5,6‑tetrabromophthalate (BEH-TEBP) and decabromodiphenylethane (DBDPE) were the most frequently detected chemicals. The highest median mass in hand wipes was that of sumEHFR (570 ng), followed by sumHBCDD (180 ng) and sumPBDE (2.9 ng). The high EHFR level was mainly driven by tetrabromobisphenol A (TBBPA) which accounted for 77% of the total mass. Positive and significant correlations were observed between FR levels in hand wipes and settled dust (0.26 < r < 0.56, p < 0.05), as well as between FR levels in hand wipes and the number of electronic consumer products at home (0.27 < r < 0.40, p < 0.05). Significant bivariate associations with number of laptops/tablets and phones/mobiles were further confirmed by multivariate linear regression analyses. Dermal exposure was estimated using the levels measured in handwipes. The estimated median dermal exposure was 2600, 840 and 6.2 pg/kg bw/d for sumEHFR, sumHBCDD and sumPBDE, respectively. Further, we compared these results with the dermal exposure as estimated indirectly by utilizing previously reported FR levels in settled dust collected from the residences of the same studied cohort. With the indirect approach, higher dermal exposures to sumPBDE but lower exposures to sumEHFR and sumHBCDD were observed compared to the direct dermal exposure estimated via hand wipes. Comparable exposure estimates between hand wipes and the indirect method were obtained for α‑, β‑tetrabromoethylcyclohexane (DBE-DBCH), DBDPE, BDE-28, -35, -49, -99, -153, 154, and -183. For other individual HFRs, the exposure estimates obtained from the two approaches were significantly different (Mann-Whitney U test, p < 0.05). Both methods gave similar dermal exposure estimates for many individual FRs. However, it is important to be aware of the value and limitations of each method when using them to estimate human exposure.
Brominated Flame Retardants and Organophosphate Esters in Preschool Dust and Children's Hand Wipes
2018. Kristin Larsson (et al.). Environmental Science and Technology 52 (8), 4878-4888Artikel
Children spend a considerable part of their day in preschool, where they may be exposed to hazardous chemicals in indoor dust. In this study, brominated flame retardants (BFRs) and organophosphate esters (OPEs) were analyzed in preschool dust ( n = 100) and children's hand wipe samples ( n = 100), and diphenyl phosphate (DPHP) was analyzed in urine ( n = 113). Here we assessed children's exposure via dust, identified predictors for chemicals in dust, and studied correlations between different exposure measures. The most abundant BFRs in dust were decabromodiphenyl ether (BDE-209) and decabromodiphenyl ethane (DBDPE) found at median levels of 270 and 110 ng/g dust, respectively. Tris(2-butoxyethyl) phosphate (TBOEP) was the most abundant OPE, found at a median level of 79 000 ng/g dust. For all OPEs and some BFRs, there were significant correlations between the levels in dust and hand wipes. In addition, triphenyl phosphate (TPHP) in preschool dust was significantly correlated with the corresponding metabolite DPHP in children's urine. The levels of pentaBDEs in dust were higher in older preschools compared with newer, whereas levels of DBDPE were higher in newer preschools. Children's estimated intakes of individual BFRs and OPEs via preschool dust were below available health-based reference values. However, there are uncertainties about the potential health effects of some emerging BFRs and OPEs.
Concentrations and variability of organophosphate esters, halogenated flame retardants, and polybrominated diphenyl ethers in indoor and outdoor air in Stockholm, Sweden
2018. Fiona Wong, Cynthia A. de Wit, Seth R. Newton. Environmental Pollution 240, 514-522Artikel
We investigated the concentrations and temporal variability of organophospate esters (OPEs), halogenated flame retardants (HFRs) and polybrominated diphenyl ethers (PBDEs) in indoor and outdoor urban air in Stockholm, Sweden over one year (2014-2015) period. The median concentrations of the three target chemical groups (OPEs, HFRs, PBDEs) were 1-2 orders of magnitude higher in indoor air than outdoor urban air. OPEs were the most abundant target FRs with median concentrations in indoor (Sigma 10OPE = 340 000 pg/m(3)) and outdoor urban (Sigma 10OPEs = 3100 pg/m(3)) air, being 3 orders of magnitude greater than for HFRs in indoor (Sigma(15)HFRs = 120 pg/m(3)) and outdoor urban (Sigma(15)HFRs = 1.6 pg/m(3)) air. In indoor air, PBDE concentrations (Sigma 17PBDEs =33 pg/m(3)) were lower than for the HFRs, but in outdoor urban air, concentrations (Sigma 17PBDEs = 1.1 pg/m(3)) were similar to HFRs. The most abundant OPEs in both the indoor and outdoor urban air were tris(2-butoxyethyl)phosphate (TBOEP), tris(chloroisopropyl) phosphate (TCIPP), tris(2-chloroethyl)phosphate (TCEP), tri-n-butyl-phosphate (TnBP), triphenyl phosphate (TPhP) and tris(1,3-dichloroisopropyl)phosphate (TDCIPP). TCIPP in indoor air was found in the highest concentrations and showed the greatest temporal variability, which ranged from 85 000 to 1 900 000 pg/m(3) during the one-year sampling period. We speculate that activities in the building, e.g. floor cleaning, polishing, construction, introduction of new electronics and changes in ventilation rate could explain its variation. Some OPEs (TnBP, TCEP, TCIPP, TDCIPP and TPhP), HFRs/PBDEs (pentabromotoluene, 2, 3-dibromopropyl 2, 4, 6-tribromophenyl ether, hexabromobenzene, BDE-28, -47, and -99) in outdoor urban air showed seasonality, with increased concentrations during the warm period (p < 0.05, Pearson's r ranged from 0.45 to 0.91). The observed seasonality for OPEs was probably due to changes in primary emission, and those for the HFRs and PBDEs was likely due to re-volatilization from contaminated surfaces.
In Vitro Inhalation Bioaccessibility of Phthalate Esters and Alternative Plasticizers Present in Indoor Dust Using Artificial Lung Fluids
2018. Katerina Kademoglou (et al.). Environmental Science and Technology Letters 5 (6), 329-334Artikel
Phthalate esters (PEs) are used as plasticizers in consumer products. Their low migration stability has resulted in the classification of PEs as major indoor contaminants. Because of PE's ubiquity and adverse health effects on humans and especially children, non-phthalate alternative plasticizers have been introduced into the market. This is the first study of in vitro inhalation bioaccessibility of PEs (e.g., DMP, DEP, and DEHP) and alternative plasticizers (e.g., DEHT and DINCH) via indoor dust to assess inhalation as an alternative route of exposure. Two artificial lung fluids were used, mimicking two distinctively different pulmonary environments: (1) artificial lysosomal fluid (ALF, pH 4.5) representing the intracellular acidic lung fluid inhaled particle contact after phagocytosis by alveolar macrophages and (2) Gamble's solution (pH 7.4), the extracellular healthy fluid for deep lung deposition of dust. DMP and DEP were highly bioaccessible (>75%), whereas highly hydrophobic compounds such as DEHP, DINCH, and DEHT were <5% bioaccessible via both artificial lung fluids. Our findings show that the inhalation bioaccessibility of PEs is primarily governed by their hydrophobicity and water solubility. Further research is necessary to develop unified and biologically relevant inhalation bioaccessibility tests, employed as part of human risk assessment of volatile and semivolatile organic pollutants.
Multi-pathway human exposure assessment of phthalate esters and DINCH
2018. Georgios Giovanoulis (et al.). Environment International 112, 115-126Artikel
Phthalate esters are substances mainly used as plasticizers in various applications. Some have been restricted and phased out due to their adverse health effects and ubiquitous presence, leading to the introduction of alternative plasticizers, such as DINCH. Using a comprehensive dataset from a Norwegian study population, human exposure to DMP, DEP, DnBP, DiBP, BBzP, DEHP, DINP, DIDP, DPHP and DINCH was assessed by measuring their presence in external exposure media, allowing an estimation of the total intake, as well as the relative importance of different uptake pathways. Intake via different uptake routes, in particular inhalation, dermal absorption, and oral uptake was estimated and total intake based on all uptake pathways was compared to the calculated intake from biomonitoring data. Hand wipe results were used to determine dermal uptake and compared to other exposure sources such as air, dust and personal care products. Results showed that the calculated total intakes were similar, but slightly higher than those based on biomonitoring methods by 1.1 to 3 times (median), indicating a good understanding of important uptake pathways. The relative importance of different uptake pathways was comparable to other studies, where inhalation was important for lower molecular weight phthalates, and negligible for the higher molecular weight phthalates and DINCH. Dietary intake was the predominant exposure route for all analyzed substances. Dermal uptake based on hand wipes was much lower (median up to 2000 times) than the total dermal uptake via air, dust and personal care products. Still, dermal uptake is not a well-studied exposure pathway and several research gaps (e.g. absorption fractions) remain. Based on calculated intakes, the exposure for the Norwegian participants to the phthalates and DINCH was lower than health based limit values. Nevertheless, exposure to alternative plasticizers, such as DPHP and DINCH, is expected to increase in the future and continuous monitoring is required.
What is the effect of phasing out long-chain per- and polyfluoroalkyl substances on the concentrations of perfluoroalkyl acids and their precursors in the environment? A systematic review
2018. Magnus Land (et al.). Environmental Evidence 7 (1)Artikel
Background: There is a concern that continued emissions of man-made per-and polyfluoroalkyl substances (PFASs) may cause environmental and human health effects. Now widespread in human populations and in the environment, several PFASs are also present in remote regions of the world, but the environmental transport and fate of PFASs are not well understood. Phasing out the manufacture of some types of PFASs started in 2000 and further regulatory and voluntary actions have followed. The objective of this review is to understand the effects of these actions on global scale PFAS concentrations. Methods: Searches for primary research studies reporting on temporal variations of PFAS concentrations were performed in bibliographic databases, on the internet, through stakeholder contacts and in review bibliographies. No time, document type, language or geographical constraints were applied in the searches. Relevant subjects included human and environmental samples. Two authors screened all retrieved articles. Dual screening of 10% of the articles was performed at title/abstract and full-text levels by all authors. Kappa tests were used to test consistency. Relevant articles were critically appraised by four reviewers, with double checking of 20% of the articles by a second reviewer. Meta-analysis of included temporal trends was considered but judged to not be appropriate. The trends were therefore discussed in a narrative synthesis. Results: Available evidence suggests that human concentrations of perfluorooctane sulfonate (PFOS), perfluorodecane sulfonate (PFDS), and perfluorooctanoic acid (PFOA) generally are declining, while previously increasing concentrations of perfluorohexane sulfonate (PFHxS) have begun to level off. Rapid declines for PFOS-precursors (e.g. perfluorooctane sulfonamide, FOSA) have also been consistently observed in human studies. In contrast, limited data indicate that human concentrations of PFOS and PFOA are increasing in China where the production of these substances has increased. Human concentrations of longer-chained perfluoroalkyl carboxylic acids (PFCAs) with 9-14 carbon atoms are generally increasing or show insignificant trends with too low power to detect a trend. For abiotic and biological environmental samples there are no clear patterns of declining trends. Most substances show mixed results, and a majority of the trends are insignificant with low power to detect a trend. Conclusions: For electrochemically derived PFASs, including PFOS and PFOA, most human studies in North America and Europe show consistent statistically significant declines. This contrasts with findings in wildlife and in abiotic environmental samples, suggesting that declining PFOS, PFOS-precursor and PFOA concentrations in humans likely resulted from removal of certain PFASs from commercial products including paper and board used in food packaging. Increasing concentrations of long-chain PFCAs in most matrices, and in most regions, is likely due to increased use of alternative PFASs. Continued temporal trend monitoring in the environment with well-designed studies with high statistical power are necessary to evaluate the effectiveness of past and continuing regulatory mitigation measures. For humans, more temporal trend studies are needed in regions where manufacturing is most intense, as the one human study available in China is much different than in North America or Europe.
Assessment of dietary exposure to organohalogen contaminants, legacy and emerging flame retardants in a Norwegian cohort
2017. Fuchao Xu (et al.). Environment International 102, 236-243Artikel
Polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), emerging halogenated flame retardants (EHFRs) and organophosphate flame retardants (PFRs) were detected in 24 h duplicate diet samples from a Norwegian cohort (n = 61), with concentrations ranging from <method limit of quantification (MLQ)-0.64 ng/g ww, <MLQ-0.70 ng/g ww, <MLQ-0.93 ng/g ww, <MLQ-0.14 ng/g ww, and <MLQ-150 ng/g ww, respectively. All studied contaminants were detected in the duplicate diet samples with detection frequencies (DF) ranging from 1.6 to 98%. The major contaminants were CB153 (median 0.042 ng/g ww), alpha-HCH (median 0.22 ng/g ww), BDE209 (median 0.45 ng/g ww), ethyl hexyl diphenyl phosphate (EHDPHP) (median 3.0 ng/g ww) and bis(2-ethylhexyl)-3,4,5,6-tetrabromo-phthalate (BEH-TEBP) (< MLQ-0.14 ng/g ww). Human dietary exposure assessment was conducted for each participant based on individual body weight and contaminant concentrations in their collected duplicate diet samples. The estimated median (95th percentile) dietary exposures for Sigma PFR, Sigma PCB, Sigma OCP, Sigma PBDE, and Sigma EHFR were 87 (340), 5.8 (27),11 (31), 1.3 (14), and <0.01 (3.4) ng/kg bw/day, respectively. The median and 95th percentile dietary exposures of most of the target analytes did not exceed the reference dose (RID), except for PCBs where 16% of the participants exceeded the RID. However, a relatively short period of such high intake is not expected to result in any adverse health effects. Participants of this cohort were exposed to higher levels of EHDPHP than any other FRs. Fish was the major dietary route for PCB, OCP and PBDE exposure, while meat was the main dietary exposure route for PFRs.
Case Study on Screening Emerging Pollutants in Urine and Nails
2017. Andreia Alves (et al.). Environmental Science and Technology 51 (7), 4046-4053Artikel
Alternative plasticizers and flame retardants (FRs) have been introduced as replacements for banned or restricted chemicals, but much is still unknown about their metabolism and occurrence in humans. We identified the metabolites formed in vitro for four alternative plasticizers (acetyltributyl citrate (ATBC), bis(2-propylheptyl) phthalate (DPHP), bis(2-ethylhexyl) terephthalate (DEHTP), bis(2ethylhexyl) adipate (DEHA)), and one FR (2,2-bis (chloromethyl)-propane-1,3-diyltetrakis(2-chloroethyl) bisphosphate (V6)). Further, these compounds and their metabolites were investigated by LC/ESI-Orbitrap-MS in urine and finger nails collected from a Norwegian cohort. Primary and secondary ATBC metabolites had detection frequencies (% DF) in finger nails ranging from 46 to 95%. V6 was identified for the first time in finger nails, suggesting that this matrix may also indicate past exposure to FRs as well as alternative plasticizers. Two isomeric forms of DEHTP primary metabolite were highly detected in urine (97% DF) and identified in finger nails, while no DPHP metabolites were detected in vivo. Primary and secondary DEHA metabolites were identified in both matrices, and the relative proportion of the secondary metabolites was higher in urine than in finger nails; the opposite was observed for the primary metabolites. As many of the metabolites present in in vitro extracts were further identified in vivo in urine and finger nail samples, this suggests that in vitro assays can reliably mimic the in vivo processes. Finger nails may be a useful noninvasive matrix for human biomonitoring of specific organic contaminants, but further validation is needed.
Chlorinated paraffins leaking from hand blenders can lead to significant human exposures
2017. Bo Yuan (et al.). Environment International 109, 73-80Artikel
Background: Chlorinated paraffins (CPs, polychlorinated n-alkanes) are versatile, high-production-volume chemicals. A previous study indicated that hand blenders leak CPs into prepared food. & para;& para;Objectives: (1) to estimate exposure to CPs from hand blender use compared to background CP exposure from diet; (2) to assess the risk from human dietary exposure to CPs from hand blender use; (3) to investigate how hand blenders leak out CPs. & para;& para;Methods: CPs were analyzed in food market baskets, in cooking oil/water samples (1 g oil/100 mL water) mixed using 16 different hand blenders, and in dismantled components of the hand blenders. & para;& para;Results: Dietary intake of CPs from food market baskets was calculated to be 4.6 mu g/day per capita for Swedish adults. Total CP amounts in oil/water leakage samples ranged from < 0.09 to 120 mu g using the hand blenders once. CP leakage showed no decreasing levels after 20 times of hand blender usage. CP profiles in the leakage samples matched those of self-lubricating bearings and/or polymer components disassembled from the hand blenders. & para;& para;Conclusions: Usage of 75% of the hand blenders tested will lead to increased human exposure to CPs. The intake of CPs for Swedish adults by using hand blenders once a day can raise their daily dietary intake by a factor of up to 26. The 95th percentile intake of CPs via using the hand blenders once a day exceeded the TDI for Swedish infants with a body weight < 7.2 kg. CP leakage came from blender components which contain CPs. The leakage may last several hundred times of hand blender use.
Dioxin-like activities, halogenated flame retardants, organophosphate esters and chlorinated paraffins in dust from Australia, the United Kingdom, Canada, Sweden and China
2017. Fiona Wong (et al.). Chemosphere 168, 1248-1256Artikel
The concentrations of organic flame retardants (FRs) and dioxin-like activities in dust collected from five countries were investigated. The correlations between the concentrations of the different groups of FRs and dioxin-like activities were examined. Chlorinated paraffins (CPs, C-9 to C-31) were found in the highest concentration (median Sigma CP 700 mu g/g, range 280-4750 mu g/g), followed by organophosphate esters (median Sigma 13OPEs 56 mu g/g, range 21-110 mu g/g), halogenated flame retardants (median Sigma(17)HFRs 3.3 mu g/g, range 0.87-14 mu g/g) and polybrominated diphenyl ethers (median Sigma 17PBDEs 2.8 mu g/g, range 0.46-11 mu g/g). There were no significant differences in concentrations of the FRs among the countries but differences in PBDE and CP congener profiles were found. BDE209 predominated in dust from Australia, the UK, Sweden and China, ranging from 50 to 70% of total PBDEs. The lowest percentage of BDE209 was found in the dust from Canada, representing only 20% of total PBDEs. For CPs in dust from Sweden, the long-chain CPs (especially C-18 congeners) predominated, while for other countries, medium-chain CPs (especially C-14 congeners) predominated. The dioxin-activities of the dusts ranged from 58 to 590 pg CALUX-TEQ/g, and had a median of 200 pg CALUX-TEQ/g. There were significant positive correlations between concentrations of PBDEs and CPs with dioxin-like activities. The dioxin-like activity may be due to the presence of polychlorinated or polybrominated dioxin/furans (PBDD/DFs) or polychlorinated naphthalenes (PCNs) in the dust. The PBDD/DFs are known impurities and degradation product of the penta-BDE mixture, and PCNs are known impurities of CPs which exhibit dioxin-like activities.
Human Exposure to Legacy and Emerging Halogenated Flame Retardants via Inhalation and Dust Ingestion in a Norwegian Cohort
2017. Joo Hui Tay (et al.). Environmental Science and Technology 51 (14), 8176-8184Artikel
In this study, we estimated human exposure to polybrominated diphenyl ethers (PBDEs), hexabromocyclo-dodecanes (HBCDDs), and several emerging flame retardants (EFRs) via inhalation and dust ingestion. Sixty indoor stationary air samples, 13 personal air samples, and 60 settled dust samples were collected from a Norwegian cohort during winter 2013. PBDEs showed the highest median concentration in dust (1200 ng/g), followed by EFRs (730 ng/g) and HBCDDs (190 ng/g). The PBDE concentrations in dust were mainly driven by BDE-209 and those of EFRs by bis(2-ethylhexyl) tetrabromophthalate. EFRs predominated in stationary air samples, with 2-ethylhexyl 2,3,4,5-tetrabromo-benzoate and 4-(1,2-dibromoethyl)-1,2-dibromocyclohexane having the highest median concentrations (150 and 25 pg/m(3) (sum of alpha- and beta-isomers), respectively). Different profiles and concentrations were observed in personal air samples compared to the corresponding stationary air samples. In relation to inhalation exposure, dust ingestion appears to be the major exposure pathway to FRs (median total exposure 230 pg/kg bw/d, accounting for more than 65% of the total exposure) for the Norwegian cohort. The calculated exposure due to air inhalation was substantially lower when the stationary air concentrations were used rather than personal air concentrations (43 pg/kg bw/d versus 130 pg/kg bw/d). This suggests that other exposure situations (such as outdoors or in offices) contributed significantly to the overall personal exposure, which cannot be included by using only a stationary air sampling technique. The median and 95th percentile exposures for all target FRs did not exceed the reference dose.
Quantifying Short-Chain Chlorinated Paraffin Congener Groups
2017. Bo Yuan (et al.). Environmental Science and Technology 51 (18), 10633-10641Artikel
Accurate quantification of short-chain chlorinated paraffins (SCCPs) poses an exceptional challenge to analytical chemists. SCCPs are complex mixtures of chlorinated alkanes with variable chain length and chlorination level; congeners with a fixed chain length (n) and number of chlorines (m) are referred to as a congener group CnClm Recently, we resolved individual CnClm by mathematically deconvolving soft ionization high-resolution mass spectra of SCCP mixtures. Here we extend the method to quantifying CnClm by introducing CnClm specific response factors (RFs) that are calculated from 17 SCCP chain-length standards with a single carbon chain length and variable chlorination level. The signal pattern of each standard is measured on APCI-QTOF-MS. RFs of each CnClm are obtained by pairwise optimization of the normal distribution's fit to the signal patterns of the 17 chain-length standards. The method was verified by quantifying SCCP technical mixtures and spiked environmental samples with accuracies of 82-123% and 76-109%, respectively. The absolute differences between calculated and manufacturer-reported chlorination degrees were 0.9 to 1.0%Cl for SCCP mixtures of 49-71%Cl. The quantification method has been replicated with ECNI magnetic sector MS and ECNI-Q:Orbitrap-MS. CnClm concentrations determined with the three instruments were highly correlated (R-2 > 0.90) with each other.
Temporal Trends of C-8-C-36 Chlorinated Paraffins in Swedish Coastal Sediment Cores over the Past 80 Years
2017. Bo Yuan (et al.). Environmental Science and Technology 51 (24), 14199-14208Artikel
Temporal trends of chlorinated paraffins (CPs) were analyzed in three sediment cores collected near different potential CP sources along the Swedish Baltic Sea coast. C-8-C-36 CPs were found in sediment dating back to the 1930s. The maximum CP concentrations found in proximity to a metropolitan sewage treatment plant, a wood related industrial area, and a steel factory were 48; 160, and 1400 ng/g d.w., respectively, in sediment sections dated from the early 1990s or the 2000s. The temporal trends agree with statistics on CP importation in Sweden or local industrial activities. MCCPs (C-14-C-17 CPs) and LCCPs (C->= 18 CPs) predominated, in most sediments with average percentage compositions of 47 +/- 20% and 37 +/- 20%, respectively. Concentrations of SCCPs in the three cores showed a decreasing trend in recent years. The temporal trends of MCCPs indicated that these are currently the predominant CPs in use. This study showed for the first time that LCCPs from C-18 to C-36, as well as C-8-C-17 CPs, are persistent in sediments over the last 30-80 years, indicating that CPs are persistent chemicals regaidless of alkane-chain lengths.
Concentrations of legacy and emerging flame retardants in air and soil on a rural-urban transect in the UK West Midlands
2016. Daniel S. Drage (et al.). Chemosphere 148, 195-203Artikel
Passive air samples were collected monthly for 6 months from 8 sites along a transect of Birmingham, United Kingdom between June 2012 and January 2013. Soil samples were collected once at each site. Average concentrations of BDE-209, ΣPBDEs17:183 and ΣPBDEs in ambient air were 150, 49, and 180 pg m−3, respectively. Atmospheric concentrations of PBDEs were negatively correlated with distance from the city centre, exhibiting an “urban pulse”. The average ΣHBCDD air concentration was 100 pg m−3, however concentrations were not correlated with distance from the city centre. Several emerging flame retardants (EFRs) were identified in air and/or soil samples: 2,3,4,5-tetrabromo-bis(2-ethylhexyl) phthalate (BEH-TEBP), 1,2-dibromo-4-(1,2 dibromoethyl)cyclohexane (TBECH or DBE-DBCH), allyl 2,4,6-tribromophenyl ether (ATE), 2-bromoallyl 2,4,6-tribromophenyl ether (BATE), decabromodiphenyl ethane (DBDPE), and dechlorane plus (DP or DDC-CO). Average concentrations of BDE-209, ΣPBDEs17:183 and ΣPBDEs in soil were 11, 3.6, and 15 ng g−1 soil organic matter. PBDE concentrations in soil were higher at sites closest to the city centre, however correlations with distance from the city centre were not significant. BDEs-47 and -99 contributed more to ΣPBDEs in soil samples than air samples, but in both, the predominant congener was BDE-209. BATE was more abundant in air than soil but ATE was abundant in soil but not air.
Deconvolution of Soft Ionization Mass Spectra of Chlorinated Paraffins To Resolve Congener Groups
2016. Bo Yuan (et al.). Analytical Chemistry 88 (18), 8980-8988Artikel
We describe and illustrate a three-step data-processing approach that enables individual congener groups of chlorinated-paraffins (CPs) to be resolved in mass spectra obtained from either-of two soft ionization methods: electron capture negative-ionization mass spectrometry (ECNI-MS) or atmospheric pressure chemical ionization mass spectrometry (APCI-MS). In the first step, general fragmentation pathways of CPs are deduced from analysis of mass spectra of individual CP congeners. In the-Second step, all possible fragment ions in the general fragmentation pathways of CPs with 10 to 20 carbon atoms are enumerated and compared to mass spectra of CP mixture standards, and a deconvolution algorithm is applied to identify fragment ions that are actually observed. In the third step, isotope permutations of the observed fragment ions are calculated and used to identify isobaric overlaps, so that mass intensities of indivichial CP congener groups can be deconvolved from the unresolved isobaric ion signal intensities in mass spectra. For a specific instrument; the three steps only need to be done once to enable deconvolution of CPs in unknown samples. This approach enables congener group-level resolution of CP mixtures in environmental samples, and: it opens up the possibility, for quantification of congener group.
Human exposure to plasticizer chemicals – correlation between indirect and biomonitoring exposure estimates in a Norwegian human cohort
2016. Georgios Giovanoulis (et al.).Konferens
Human exposure, hazard and risk of alternative plasticizers to phthalate esters
2016. Thuy T. Bui (et al.). Science of the Total Environment 541, 451-467Artikel
Alternative plasticizers to phthalate esters have been used for over a decade, but data regarding emissions, human exposure and health effects are limited. Here we review 20 alternative plasticizers in current use and their human exposure, hazard and risk. Physicochemical properties are collated for these diverse alternatives and log K-OW values range over 15 orders of magnitude and log K-AW and log K-OA values over about 9 orders of magnitude. Most substances are hydrophobic with low volatility and are produced in high volumes for use in multiple applications. There is an increasing trend in the total use of alternative plasticizers in Sweden compared to common phthalate esters in the last 10 years, especially for DINCH. Evaluative indoor fate modeling reveals that most alternatives are distributed to vertical surfaces (e.g. walls or ceilings). Only TXIB and GTA are predicted to be predominantly distributed to indoor air. Human exposure data are lacking and clear evidence for human exposure only exists for DEHT and DINCH, which show increasing trends in body burdens. Human intake rates are collected and compared with limit values with resulting risk ratios below 1 except for infant's exposure to ESBO. PBT properties of the alternatives indicate mostly no reasons for concern, except that TEHPA is estimated to be persistent and TCP toxic. A caveat is that non-standard toxicological endpoint results are not available and, similar to phthalate esters, the alternatives are likely pseudo-persistent. Keydata gaps for more comprehensive risk assessment are identified and include: analytical methods to measure metabolites in biological fluids and tissues, toxicological information regarding non-standard endpoints such as endocrine disruption and a further refined exposure assessment in order to consider high risk groups such as infants, toddlers and children.
In vitro bioaccessibility of plasticisers in indoor dust using simulated lung fluids
2016. Aikaterinin Kademoglou (et al.).Konferens
Assessment of external routes for human exposure to phthalate plasticizers in indoor environment. A case study based on a Norwegian cohort of 61 adults in Oslo area.
2015. Georgios Giovanoulis (et al.).Konferens
Emerging Flame Retardants, PBDEs, and HBCDDs in Indoor and Outdoor Media in Stockholm, Sweden
2015. Seth Newton, Ulla Sellström, Cynthia A. de Wit. Environmental Science and Technology 49 (5), 2912-2920Artikel
Dust, indoor air, outgoing air from ventilation systems, outdoor air, and soil were sampled in and around Stockholm, Sweden during the winter and spring 2012. The concentrations of several emerging flame retardants (EFRs), polybrominated diphenyl ethers (PBDEs), and isomers of hexabromocyclododecane (HBCDD) were measured. The most commonly found EFR was 1,2-dibromo-4-(1,2 dibromoethyl)cyclohexane (TBECH or DBE-DBCH), which was found in nearly all indoor, ventilation, and outdoor air samples, most dust samples, but not in soil samples. Other frequently detected EFRs included pentabromotoluene (PBT), hexabromobenzene (HBB), 2,3,4,5-tetrabromo-ethylhexylbenzoate (EHTBB), 2,3,4,5-tetrabromo-bis(2-ethylhexyl) phthalate (BEH-TEBP), and decabromodiphenyl ethane (DBDPE). PBDE concentrations were significantly lower in air and dust samples compared to a previous study in Stockholm. In outdoor air, DBE-DBCH, PBT, EHTBB, DBDPE, and PBDEsshowed an “urban pulse” with concentrations increasing as samples were taken in more urban areas compared to rural areas. These EFRs show similar environmental behavior asPBDEs. Higher brominated BDEs showed this same urban pulse in soil but lower brominated BDEs did not. Air–soil fugacity fractions were calculated, and these indicated that most compounds are undergoing net deposition from atmosphere to soil, with the higher brominated PBDEs furthest from equilibrium.
Estimated intakes of brominated flame retardants via diet and dust compared to internal concentrations in a Swedish mother-toddler cohort
2015. Leena M. O. Sahlström (et al.). International journal of hygiene and environmental health (Print) 218 (4), 422-432Artikel
Tri-decabrominated diphenyl ethers (tri-decaBDEs), isomer-specific hexabromocyclododecanes (HBCDs) and 14 emerging brominated flame retardants (EBFRs) were determined in Swedish market basket samples, two pooled breast milk samples and house dust collected in homes of first-time mothers. Daily dietary and dust intakes were estimated for the mothers and their toddlers and compared to previously reported levels in serum of both the mothers and toddlers and in feces of the toddlers (n = 20). Diet was the main contributor for intake of Sigma pentaBDE and alpha-tetrabromoethylcyclohexane (DBE-DBCH) for both mothers and toddlers. For Sigma octaBDE, Sigma HBCD and pentabromobenzene (PBBz), dietary intake was more important for mothers while house dust ingestion was more important for toddlers. House dust was the main exposure route for Sigma decaBDE, decabromodiphenyl ethane (DBDPE), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB), bis(2-ethylhexyl)tetrabromophthalate (BEH-TEBP), bis(2,4,6-tribromophenoxy) ethane (BTBPE) and pentabromotoluene (PBT) for both mothers and toddlers. Significant correlations (Spearmans, alpha<0.05) were found between the mothers' BDE serum concentrations and their consumption of meat and fish while no correlations were found between BFR dietary intake and serum or feces concentrations in toddlers. Octa-decaBDE congener concentrations in serum and feces of toddlers were significantly correlated to those in house dust. BDE-207 and -208 concentrations in serum of mothers were significantly correlated with the nonaBDEs in house dust. The correlations between house dust and internal concentrations and comparison of the house dust and dietary contributions to the estimated daily intakes suggest that dust exposure plays a larger role for the octa-decaBDE body burden in toddlers than in their mothers.
Exploring the planetary boundary for chemical pollution
2015. Miriam L. Diamond (et al.). Environment International 78, 8-15Artikel
Rockstrom et al. (2009a, 2009b) have warned that humanity must reduce anthropogenic impacts defined by nine planetary boundaries if unacceptable global change is to be avoided. Chemical pollution was identified as one of those boundaries for which continued impacts could erode the resilience of ecosystems and humanity. The central concept of the planetary boundary (or boundaries) for chemical pollution (PBCP or PBCPs) is that the Earth has a finite assimilative capacity for chemical pollution, which includes persistent as well as readily degradable chemicals released at local to regional scales, which in aggregate threaten ecosystem and human viability. The PBCP allows humanity to explicitly address the increasingly global aspects of chemical pollution throughout a chemical's life cycle and the need for a global response of internationally coordinated control measures. We submit that sufficient evidence shows stresses on ecosystem and human health at local to global scales, suggesting that conditions are transgressing the safe operating space delimited by a PBCP. As such, current local to global pollution control measures are insufficient. However, while the PBCP is an important conceptual step forward, at this point single or multiple PBCPs are challenging to operationalize due to the extremely large number of commercial chemicals or mixtures of chemicals that cause myriad adverse effects to innumerable species and ecosystems, and the complex linkages between emissions, environmental concentrations, exposures and adverse effects. As well, the normative nature of a PBCP presents challenges of negotiating pollution limits amongst societal groups with differing viewpoints. Thus, a combination of approaches is recommended as follows: develop indicators of chemical pollution, for both control and response variables, that will aid in quantifying a PBCP(s) and gauging progress towards reducing chemical pollution; develop new technologies and technical and social approaches to mitigate global chemical pollution that emphasize a preventative approach; coordinate pollution control and sustainability efforts; and facilitate implementation of multiple (and potentially decentralized) control efforts involving scientists, civil society, government, non-governmental organizations and international bodies.
Feasibility Study of Feces for Noninvasive Biomonitoring of Brominated Flame Retardants in Toddlers
2015. Leena M. O. Sahlström (et al.). Environmental Science and Technology 49 (1), 606-615Artikel
This study investigated the feasibility of using feces as a noninvasive matrix to estimate serum concentrations of brominated flame retardants (BFRs) in toddlers for biomonitoring purposes. Tri- to decabrominated diphenyl ethers (tri-decaBDEs), isomer-specific hexabromocyclododecanes, and 16 emerging BFRs were determined in feces from 22 toddlers (11-15 months of age), and results were compared to previously analyzed matched serum samples. BDE-47, -153, -196, -197, -203, -206, -207, -208, and -209 were detected in the feces creating a matched data set (feces-serum, n = 21). Tetra-octaBDE concentrations were significantly higher (Student's paired comparisons t test, a = 0.05) in serum versus feces with BDE-153 having the highest mean difference between the sample matrices. BDE-209 was found in significantly higher concentrations in feces compared to serum. Significant correlations (Pearson's, alpha = 0.05) between congener-specific concentrations in feces and serum were found for all BDEs except BDE-197 and -203. The feces-serum associations found can be used to estimate serum concentrations of tetra-decaBDEs from feces concentrations and enable a noninvasive sampling method for biomonitoring BDEs in toddlers.
Modelling isotopic peak distributions of chlorinated paraffins homologue groups in high resolution mass spectrometry in soft ionization modes
2015. Bo Yuan (et al.).Konferens
Planetary boundaries: Guiding human development on a changing planet
2015. Will Steffen (et al.). Science 347 (6223)Artikel
The planetary boundaries framework defines a safe operating space for humanity based on the intrinsic biophysical processes that regulate the stability of the Earth system. Here, we revise and update the planetary boundary framework, with a focus on the underpinning biophysical science, based on targeted input from expert research communities and on more general scientific advances over the past 5 years. Several of the boundaries now have a two-tier approach, reflecting the importance of cross-scale interactions and the regional-level heterogeneity of the processes that underpin the boundaries. Two core boundaries-climate change and biosphere integrity-have been identified, each of which has the potential on its own to drive the Earth system into a new state should they be substantially and persistently transgressed.
What is the effect of phasing out long-chain per- and polyfluoroalkyl substances on the concentrations of perfluoroalkyl acids and their precursors in the environment? A systematic review protocol
2015. Magnus Land (et al.). Environmental Evidence 4 (1)Artikel
There is a growing concern in Sweden and elsewhere that continued emissions of per- and polyfluoroalkyl substances (PFASs) may cause environmental as well as human health effects. PFASs are a broad class of man-made substances that have been produced and used in both commercial products and industrial processes for more than 60 years. Although the production and use of some PFASs has been phased-out in some parts of the world, it is not known what effect these actions to date have had on PFAS concentrations in the environment. Owing to the wide diversity of PFASs, it is difficult to generalize their properties, environmental fate and production histories. However, the strength and stability of the C-F bond renders the perfluoroalkyl moieties resistant to heat and environmental degradation. Several PFASs are now occurring even in very remote areas in large parts of the world, but the environmental transport and fate of substances within this group is not well understood. A systematic review may be able to determine whether the concentrations of these substances in different environments are changing in any particular direction with time, and whether the phase-outs have had any effects on the concentration trends.
Searches for primary research studies reporting on temporal variations of PFAS concentrations in the environment will be performed in the scientific literature as well as in other reports. Relevant samples include both abiotic and biological samples including humans. No particular time, document type, language or geographical constraints will be applied. Two authors will screen all retrieved articles. Double screening of about 10% of the articles will be performed by all authors at both title/abstract and full-text levels. Kappa tests will be used to test if the screening is consistent. Relevant articles will be critically appraised by four authors (double checking of 25% of the articles). Quality assessment will focus on selection bias, dating of samples, sample integrity and analytical procedures. Data synthesis will be based on statistical analysis of temporal concentration trends.
Brominated Flame Retardants in Matched Serum Samples from Swedish First-Time Mothers and Their Toddlers
2014. Leena M. O. Sahlström (et al.). Environmental Science and Technology 48 (13), 7584-7592Artikel
Tri-decabrominated diphenyl ethers and 21 other flame retardants were determined in matched serum samples from 24 Swedish mothers (Uppsala county) and their toddlers (11-15 months of age). The median concentrations of individual polybrominated diphenyl ethers (PBDEs) ranged from 0.036 to 0.95 ng/g lipid in mothers and from 0.057 to 1.5 ng/g lipid in toddlers. BDE-209 was detected in all but one sample. BDE-153 was the predominant congener in the mothers while in toddlers, BDE-209 was found in the highest concentrations. The levels of BDE-47, -100, -207, -208, and -209 in toddlers were significantly higher (p < 0.05) than those in their mothers. Dechlorane Plus (anti- and syn-) and alpha- and beta-tetrabromoethylcyclohexane were detected in a few (2-4) serum samples from both mothers and toddlers. This study also reports concentrations of alpha-HBCD and eight emerging brominated flame retardants (EBFRs) in the standard reference material serum (SRM 1958, NIST). Lack of correlations between the matched serum samples indicate different exposure routes for octa-decaBDEs in mothers versus toddlers. Congener-to-congener correlations within the mother or toddler cohorts suggest diet as an important exposure pathway for tetra-nonaBDEs for mothers, breastfeeding as a predominant exposure pathway for tetra-hexaBDEs, and dust for octa-decaBDEs for toddlers.
Identifying Chemicals That Are Planetary Boundary Threats
2014. Matthew MacLeod (et al.). Environmental Science and Technology 48 (19), 11057-11063Artikel
Rockstrom et al. proposed a set of planetary boundaries that delimit a safe operating space for humanity Many of the planetary boundaries that have so far been identified are determined by chemical agents. Other chemical pollution-related planetary boundaries likely exist, but are currently unknown. A chemical posed an unknown planetary boundary threat if it simultaneously fulfills three conditions (1) it has an unknown disruptive effect on a vital Earth system process; (2) the disruptive effect is not discovered until it is a problem at the global scale, and (3) the effect is not readily reversible. In this paper, we outline scenarios in which chemical could fulfill each of the three conditions, then use the scenarios as the basis to define chemical profiles that fit each scenario. The chemical profiles are defined in terms of the nature of the effect of the chemical and the nature of exposure of the environment to the chemical. Priortization of chemicals in commerce against some of the profiles appears feasible, but there are considerable uncertainites and scientific challenges that must be addressed. Most challenging is prioritizing chemicals for the potential to have a currently unknown effect on a vital. Earth system process. We conclude that the most effective strategy currently available to identify chemicals that are planetary boundary threats is prioritization against profiles defined in terms of environmental exposure combined with monitoring and study of the biogeochemical process that underlie vital Earth system processes to identify currently unknown disruptive effects.
Confronting Unknown Planetary Boundary Threats from Chemical Pollution
2013. Linn Persson (et al.). Environmental Science and Technology 47 (22), 12619-12622Artikel
Rockström et al. proposed a set of planetary boundaries that delimitate a “safe operating space for humanity”. One of the planetary boundaries is determined by “chemical pollution”, however no clear definition was provided. Here, we propose that there is no single chemical pollution planetary boundary, but rather that many planetary boundary issues governed by chemical pollution exist. We identify three conditions that must be simultaneously met for chemical pollution to pose a planetary boundary threat. We then discuss approaches to identify chemicals that could fulfill those conditions, and outline a proactive hazard identification strategy that considers long-range transport and the reversibility of chemical pollution.
Persistence, Bioaccumulation, and Toxicity of Halogen-Free Flame Retardants
2013. Susanne L. Waaijers (et al.). Reviews of Environmental Contamination and Toxicology, 1-71Kapitel
Polymers are synthetic organic materials having a high carbon and hydrogen content, which make them readily combustible. Polymers have many indoor uses and their flammability makes them a fire hazard. Therefore, flame retardants (FRs) are incorporated into these materials as a safety measure. Brominated flame retardants (BFRs), which accounted for about 21% of the total world market of FRs, have several unintended negative effects on the environment and human health. Hence, there is growing interest in finding appropriate alternative halogen-free flame retardants (HFFRs). Many of these HFFRs are marketed already, although their environ- mental behavior and toxicological properties are often only known to a limited extent, and their potential impact on the environment cannot yet be properly assessed. Therefore, we undertook this review to make an inventory of the available data that exists (up to September 2011) on the physical-chemical properties, pro- duction volumes, persistence, bioaccumulation, and toxicity (PBT) of a selection of HFFRs that are potential replacements for BFRs in polymers. Large data gaps were identified for the physical-chemical and the PBT properties of the reviewed HFFRs. Because these HFFRs are currently on the market, there is an urgent need to fill these data gaps. Enhanced transparency of methodology and data are needed to reevaluate certain test results that appear contradictory, and, if this does not provide new insights, further research should be performed. TPP has been studied quite extensively and it is clearly persistent, bioaccumulative, and toxic. So far, RDP and BDP have demonstrated low to high ecotoxicity and persistence. The compounds ATH and ZB exerted high toxicity to some species and ALPI appeared to be persistent and has low to moderate reported ecotoxicity. DOPO and MPP may be persistent, but this view is based merely on one or two studies, clearly indicating a lack of information. Many degradation studies have been performed on PER and show low persistence, with a few exceptions. Additionally, there is too l ittle information on the bioaccumulation potential of PER. APP mostly has low PBT properties; however, moderate ecotoxicity was reported in two studies. Mg(OH)₂, ZHS, and ZS do not show such remarkably high bioaccumulation or toxicity, but large data gaps exist for these compounds also. Nevertheless, we consider the latter compounds to be the most promising among alternative HFFRs. To assess whether the presently reviewed HFFRs are truly suitable alternatives, each compound should be examined individually by comparing its PBT values with those of the relevant halogenated flame retardant. Until more data are available, it remains impossible to accurately evaluate the risk of each of these compounds, including the ones that are already extensively marketed.
Two organophosphorus flame retardants, resorcinol bis (diphenylphosphate)(PBDPP) and bisphenol A bis (diphenylphosphate) (BPA-BDPP) used as alternatives for BDE209 detected in dust
2013. Sicco H. Brandsma (et al.). Environmental Science and Technology 47 (24), 14434-14441Artikel
Resorcinol bis(diphenylphosphate) (RBDPP) and bisphenol A bis(diphenylphosphate) (BPA-BDPP) are two halogen-free organophosphorus flame retardant (PFRs) that are used as an alternative for the decabromodiphenyl ether (Deca-BDE) technical mixture in TV/flatscreen housing and other electronic consumer products.' In this study, dust samples were collected from various microenvironments in The Netherlands (houses, cars), Greece.(houses), and Sweden (apartments, cars, furniture stores, electronics stores) and analyzed for RBDPP and BPA-BDPP. Additionally, the dust samples from The Netherlands were analyzed for decabromodiphenyl ether (BDE-209) for comparison and for TPHP, which is a byproduct in the RBDPP and BPA-BDPP technical products. BPA-BDPP was detected in almost all dust samples from The Netherlands, Greece, and Sweden. Highest concentrations were found in dust samples collected on electronic equipment from all three countries with BPA-BDPP levels ranging from <0.1 to 1300 mu g/g and RBDPP levels from <0.04 to 520 mu g/g. RBDPP and BPA-BDPP levels in dust collected further away from the electronics (source) were usually lower. BDE-209 levels in The Netherlands dust samples collected on and around the electronics were similar and much lower than the BPA-BDPP/RBDPP levels, indicating that the electronics were not the source of BDE-209. Strong positive correlations were found between TPHP concentrations and those of RBDPP (r = 0.805) and BPA-BDPP (r = 0.924), probably due to TPHP being a byproduct in commercial RBDPP and BPA-BDPP mixtures in electronics. To our knowledge, this is the first time that RBDPP and BPA-BDPP were detected in dust samples from Europe.
Clean-up method for determination of established and emerging brominated flame retardants in dust
2012. Leena Sahlström, Ulla Sellström, Cynthia A. de Wit. Analytical and Bioanalytical Chemistry 404 (2), 459-466Artikel
A clean-up method was developed to enable the determination of tri-decabrominated diphenyl ethers, isomer-specific hexabromocyclododecanes (HBCDs), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), decabromodiphenyl ethane (DBDPE), (2-ethylhexyl)tetrabromobenzoate (TBB), and bis(2-ethylhexyl)tetrabromophthalate (TBPH) in the same dust sample extract using reasonable amounts of solvents and without dividing the sample. After extraction, the sample was separated on a silica column into three fractions that were subsequently cleaned up individually. The polybrominated diphenyl ethers (PBDEs) and DBDPE were eluted in Fraction I, TBB, TBPH, and BTBPE in Fraction II, and HBCDs in Fraction III. Fractions I and II were analyzed using gas chromatography/mass spectrometry and Fraction III using liquid chromatography/mass spectrometry. The method gave good recoveries (60-120%), precise results using (13) C-labelled internal standards and was accurate when comparing results to certified values (PBDEs in NIST SRM 2585). The method was applied to dust samples from the Stockholm (Sweden) area. All the emerging brominated flame retardants (BFRs) studied, except BTBPE, were present in all the samples in quantifiable concentrations, often higher than the PBDEs. BTBPE was quantified in only one sample. It is evident that emerging BFRs are present in Swedish homes, and these compounds should be included in the BFR analyses of indoor environments.
Comparisons of polybrominated diphenyl ether and hexabromocyclododecane concentrations in dust collected with two sampling methods and matched breast milk samples
2012. Justina A. Björklund (et al.). Indoor Air 22 (4), 279-288Artikel
Household dust from 19 Swedish homes was collected using two different sampling methods: from the occupants own home vacuum cleaner after insertion of a new bag and using a researcher-collected method where settled house dust was collected from surfaces above floor level. The samples were analyzed for 16 polybrominated diphenyl ether (PBDE) congeners and total hexabromocyclododecane (HBCD). Significant correlations (r = 0.600.65, Spearman r = 0.470.54, P < 0.05) were found between matched dust samples collected with the two sampling methods for ?OctaBDE and ?DecaBDE but not for ?PentaBDE or HBCD. Statistically significantly higher concentrations of all PBDE congeners were found in the researcher-collected dust than in the home vacuum cleaner bag dust (VCBD). For HBCD, however, the concentrations were significantly higher in the home VCBD samples. Analysis of the bags themselves indicated no or very low levels of PBDEs and HBCD. This indicates that there may be specific HBCD sources to the floor and/or that it may be present in the vacuum cleaners themselves. The BDE-47 concentrations in matched pairs of VCBD and breast milk samples were significantly correlated (r = 0.514, P = 0.029), indicating that one possible exposure route for this congener may be via dust ingestion. Practical Implications The statistically significant correlations found for several individual polybrominated diphenyl ether (PBDE) congeners, ?OctaBDE and ?DecaBDE between the two dust sampling methods in this study indicate that the same indoor sources contaminate both types of dust or that common processes govern the distribution of these compounds in the indoor environment. Therefore, either method is adequate for screening ?OctaBDE and ?DecaBDE in dust. The high variability seen between dust samples confirms results seen in other studies. For hexabromocyclododecane (HBCD), divergent results in the two dust types indicate differences in contamination sources to the floor than to above-floor surfaces. Thus, it is still unclear which dust sampling method is most relevant for HBCD as well as for ?PentaBDE in dust and, further, which is most relevant for determining human exposure to PBDEs and HBCD.
Indoor Air Is a Significant Source of Tri-decabrominated Diphenyl Ethers to Outdoor Air via Ventilation Systems
2012. Justina Awasum Björklund (et al.). Environmental Science and Technology 46 (11), 5876-5884Artikel
Ventilation of indoor air has been hypothesized to be a source of PBDEs to outdoors. To study this, tri-decabrominated diphenyl ethers were analyzed in outgoing air samples collected inside ventilation systems just before exiting 33 buildings and compared to indoor air samples from microenvironments in each building collected simultaneously. Median Sigma 10PBDE (BDE- 28, -47, -99, -153, -183, -197, -206, -207, -208, -209) concentrations in air from apartment, office and day care center buildings were 93, 3700, and 660 pg/m(3) for outgoing air, and 92, 4700, and 1200 pg/m(3) for indoor air, respectively. BDE-209 was the major congener found. No statistically significant differences were seen for individual PBDE concentrations in matched indoor and outgoing air samples, indicating that outgoing air PBDE concentrations are equivalent to indoor air concentrations. PBDE concentrations in indoor and outgoing air were higher than published outdoor air values suggesting ventilation as a conduit of PBDEs, including BDE-209, from indoors to outdoors. BDE-209 and sum of BDE-28, -47, -99, and -153 emissions from indoor air to outdoors were roughly estimated to represent close to 90% of total emissions to outdoor air for Sweden, indicating that contaminated indoor air is an important source of PBDE contamination to outdoor air.
Tri-decabrominated diphenyl ethers and hexabromocyclododecane in indoor air and dust from Stockholm microenvironments 1: Levels and profiles
2012. Kaj Thuresson, Justina Awasum Björklund, Cynthia A. de Wit. Science of the Total Environment 414, 713-721Artikel
Indoor air (gas and particle phase) and dust samples were collected from 10 houses, 44 apartments, 10 day care centers, 10 offices, 17 new cars and two car dealership halls from Stockholm. Sweden, and analyzed for polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD). Median Sigma PBDE concentrations in air were 330, 58, 4000, 14 000 and 510 pg/m(3) in houses, apartments, day care centers, offices and cars, respectively. Median Sigma PBDE concentrations in dust were 510, 1400, 1200, 1200 and 1400 ng/g in houses, apartments, day care centers, offices and cars, respectively. HBCD was detected in most dust samples (median range, 45-340 ng/g) but only in a few air samples (median range, <1.6-2.0 pg/m(3)). For all microenvironments, the brominated flame retardant (BFR) found in highest concentration in air was Sigma DecaBDE, primarily BDE-209, followed by Sigma PentaBDE, and in dust, Sigma DecaBDE, followed by HBCD (offices, day care centers, cars) or Sigma PentaBDE (houses, apartments). Positive correlations were found between matched air and dust samples for Sigma PentaBDE, but not for Sigma DecaBDE.
Tri-decabrominated diphenyl ethers and hexabromocyclododecane in indoor air and dust from Stockholm microenvironments 2: Indoor sources and human exposure
2012. Cynthia A. de Wit, Justina Awasum Björklund, Kaj Thuresson. Environment International 39 (1), 141-147Artikel
Data on polybrominated diphenyl ether (PBDE) and hexabromocyclododecane (HBCD) concentrations from Stockholm, Sweden, indoor microenvironments were combined with information from detailed questionnaires regarding the sampling location characteristics, including furnishing and equipment present. These were used to elucidate relationships between possible flame-retarded sources and the contaminant concentrations found in air and dust. Median concentration ranges of Sigma Penta-, Sigma Octa-, Sigma DecaBDE and HBCD from all microenvironments were 19-570, 1.7-280, 29-3200 and <1.6-2 pg/m(3) in air and 22-240, 6.1-80, 330-1400 and 45-340 ng/g in dust, respectively. Significant correlations were found between concentrations of some PBDEs and HBCD in air and/or dust and the presence of electronic/electrical devices, foam furniture, PUF mattresses and synthetic bed pillows in, as well as floor area and construction year of the microenvironment. Car interiors were a source to indoor air in dealership halls. Using median and maximum concentrations of Sigma Penta-, Sigma Octa-, Sigma DecaBDE and HBCD in air and dust, adult and toddler (12-24 months) intakes from inhalation and dust ingestion were estimated. Toddlers had higher estimated intakes of Sigma Penta-, Sigma DecaBDE and HBCD (7.8, 43, 7.6 ng/d, respectively) from dust ingestion than adults (5.8, 38, 6.0 ng/d, respectively). Air inhalation in offices was also an important exposure pathway for Sigma Penta-, Sigma Octa- and Sigma DecaBDE in adults. For Sigma PentaBDE and HBCD, air inhalation and dust ingestion play minor roles when compared to previously published Swedish dietary intakes (median exposures). However, in worst case scenarios using maximum concentrations, dust ingestion may represent 77 and 95% of toddler intake for Sigma PentaBDE and HBCD, respectively.
Novel brominated flame retardants: A review of their analysis, environmental fate and behaviour
2011. Adrian Covaci (et al.). Environment International 37 (2), 532-556Artikel
This review summarises current knowledge about production volumes, physico-chemical properties, analysis, environmental occurrence, fate and behaviour and human exposure to the novel brominated flame retardants (NBFRs). We define the term NBFRs as relating to BFRs which are new to the market or newly/recently observed in the environment. Restrictions and bans on the use of some polybrominated diphenyl ether (PBDE) formulations, in many jurisdictions, have created a market for the use of NBFRs. To date, most data on NBFRs have arisen as additional information generated by research designed principally to study more traditional BFRs, such as PBDEs. This has led to a wide variety of analytical approaches for sample extraction, extract purification and instrumental analysis of NBFRs. An overview of environmental occurrence in abiotic matrices, aquatic biota, terrestrial biota and birds is presented. Evidence concerning the metabolism and absorption of different NBFRs is reviewed. Human exposure to NBFRs via different exposure pathways is discussed, and research gaps related to analysis, environmental sources, fate, and behaviour and human exposure are identified.
Temporal trends of polybrominated diphenyl ethers and hexabromocyclododecane in Swedish Peregrine Falcon (Falco peregrinus peregrinus) eggs
2011. Anna-Karin Johansson (et al.). Environment International 37 (4), 678-686Artikel
A temporal trend study of brominated flame retardants in eggs from peregrine falcon (Falco peregrinus peregrinus), a terrestrial bird of prey, is presented. Eggs collected between 1974 and 2007 were analyzed for the major constituents of the Penta-. Octa- and Decabromodiphenyl ether technical products (BDE-47, -99, -100, -153, -183 and -209), and hexabromocyclododecane (HBCD). Concentrations of BDE-99, -100, -153, -183, -209 and HBCD increased from 1974 to 2000. After the early 2000s. BDE-99, -100, -153 and -183 concentrations decreased, whereas BDE-209 and HBCD concentrations continued to increase. No temporal trend was detected for BDE-47. Rates of increase also differed, with BDE-99 and -100 increasing 3-fold between the 1980s and mid-1990s, and BDE-153 and -183 increasing approximately 10-fold during the same period. The average yearly increase was 15% and 11% for BDE-209 and HBCD, respectively, based on log-linear regression trends. There is a change in BDE congener patterns over time, with a shift from the predominance of BDE-99 and -47 until the late 1980s. to BDE-153 becoming the predominant congener later on. BFR temporal trends in Swedish peregrine falcon eggs reflect European BFR usage patterns.
Brominated flame retardants in the Arctic environment - trends and new candidates.
2010. Cynthia A de Wit, Dorte Herzke, Katrin Vorkamp. The Science of the total environment 408 (15), 2885-2918Artikel
Polybrominated diphenyl ethers (PBDEs) containing two to 10 bromines are ubiquitous in the Arctic, in both abiotic and biotic samples. Hexabromocyclododecane (HBCD) is also ubiquitous in the Arctic, with the gamma-HBCD isomer predominating in air, the alpha-HBCD isomer predominating in biota and similar concentrations of alpha-, beta- and gamma-HBCD found in marine sediments. Other brominated flame retardants (BFRs) found in some Arctic samples are polybrominated biphenyls (PBBs), tetrabromobisphenol A (TBBPA), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), hexabromobenzene (HxBBz), pentabromoethylbenzene (PBEB), pentabromotoluene (PBT), and 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH). Temporal trends of tetra- to heptaBDEs and HBCD show increasing concentrations or a tendency to levelling off depending on the matrix (air, sediment, biota) and location, but no uniform picture for the Arctic emerges. BDE-209 concentrations are increasing in air. PBDEs and HBCD spatial trends in seabirds and marine mammals are similar to those seen previously for polychlorinated biphenyls (PCBs), with highest concentrations found in organisms from East Greenland and Svalbard. These trends indicate western Europe and eastern North America as important source regions of these compounds via long range atmospheric transport and ocean currents. Latitudinal trends showed lower concentrations and fluxes of PBDEs at higher latitudes. The tetra-hexaBDEs and alpha-HBCD biomagnify in Arctic food webs. Results for BDE-209 are more conflicting, showing either only low or no biomagnification potential. PBDE and HBCD concentrations are lower in terrestrial organisms and higher in marine top predators such as some killer whale populations in Alaska and glaucous gulls from the Barents Sea area. Higher concentrations are seen near populated areas indicating local sources. Findings of BTBPE, HxBBz, PBEB, PBT and TBECH in seabirds and/or marine mammals indicate that these compounds reach the Arctic, most probably by long range atmospheric transport and accumulate in higher trophic level organisms and that increasing use as PBDE replacements will lead to increasing concentrations.
Indoor Contamination with Hexabromocyclododecanes, Polybrominated Diphenyl Ethers, and Perfluoroalkyl Compounds: An Important Exposure Pathway for People?
2010. Stuart Harrad (et al.). Environmental Science and Technology 44 (9), 3221-3231Artikel
This review underlines the importance of indoor contamination as a pathway of human exposure to hexabromocyclododecanes (HBCDs), polybrominated diphenyl ethers (PBDEs), and perfluoroalkyl compounds (PFCs). There is ample evidence of substantial contamination of indoor dust with these chemicals and that their concentrations in indoor air exceed substantially those outdoors. Studies examining the relationship between body burden and exposure via indoor dust are inconsistent while some indicate a link between body burdens and PBDE and HBCD exposure via dust ingestion, others find no correlation. Likewise, while concentrations in indoor dust and human tissues are both highly skewed, this does not necessarily imply causality. Evidence suggests exposure via dust ingestion is higher for toddlers than adults. Research priorities include identifying means of reducing indoor concentrations and indoor monitoring methods that provide the most ""biologically-relevant"" measures of exposure as well as monitoring a wider range of microenvironment categories. Other gaps include studies to improve understanding of the following: emission rates and mechanisms via which these contaminants migrate from products into indoor air and dust; relationships between indoor exposures and human body burdens; relevant physicochemical properties; the gastrointestinal uptake by humans of these chemicals from indoor dust; and human dust ingestion rates.
Levels and trends of new contaminants, temporal trends of legacy contaminants and effects of contaminants in the Arctic: Preface
2010. Cynthia A. de Wit, Derek Muir. Science of the Total Environment 408 (15), 2852-2853Artikel
San Antonio Statement on brominated and chlorinated flame retardants
2010. Joseph DiGangi (et al.). Environmental Health Perspectives 118 (12), A516-A518Artikel
Trends of legacy and new persistent organic pollutants in the circumpolar arctic: Overview, conclusions, and recommendations
2010. Derek C. G. Muir, Cynthia A. de Wit. Science of the Total Environment 408 (15), 3044-3051Artikel
This article provides an overview of key findings in the reviews in this special issue on the assessment of persistent organic pollutants (POPS) under the Arctic Monitoring and Assessment Program (AMAP), identifies knowledge gaps, and presents conclusions and recommendations for future work. The articles in this special issue summarize the peer reviewed literature and selected technical reports on trends of concentrations and possible biological effects of POPs in the Arctic published up to early 2009. Crown Copyright
A mass balance of tri-hexabrominated diphenyl ethers in lactating cows.
2009. Amelie Kierkegaard (et al.). Environmental Science and Technology 43 (7), 2602-2607Artikel
Beef and dairy products can be important vectors of human exposure to polybrominated diphenylethers (BDEs), and hence an understanding of BDE transfer from feed to cows' milk and tissue is important for BDE exposure assessment The fate of tri- to hexaBDEs in lactating cows exposed to a naturally contaminated diet was studied by analyzing feed, feces, and milk samples from a mass balance study. Tissue distribution was studied in one cowslaughtered afterthe experiment The carryover rates from feed to milk ranged from 0.15 to 0.35 for the major congeners. Lower values were observed for several of the tetrabrominated congeners, and this was attributed to metabolism. The dietary absorption efficiency decreased with increasing octanol-water partition coefficient of the BDE congener. The absorption behavior was consistent with a model based on chemical lipophilicity, but agreed less well with a model based on effective molecular diameter, and it violated Lipinski's "rule of 5". The lipid normalized concentrations were similar in all tissues analyzed including liver and milk, suggesting that tissue distribution is governed by partitioning into lipids. Overall, the behavior of the tri- to hexaBDEs was consistent with that observed for other classes of halogenated aromatic contaminants such as PCBs and PCDD/Fs, but it differed markedly from the behavior of the hepta- decaBDEs.
A safe operating space for humanity
2009. Johan Rockström (et al.). Nature 461 (24 Sept), 472-475Artikel
Perfluoroalkyl compounds (PFCs) in indoor dust: concentrations, human exposure estimates, and sources
2009. Justina Awasum Björklund, Kaj Thuresson, Cynthia A. De Wit. Environmental Science and Technology 43 (7), 2276-2281Artikel
Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are globally distributed, persistent, toxic, and are found in human blood and serum. Exposure pathways are not well characterized. To better understand indoor dust ingestion as a potential pathway for human exposure, we determined the concentrations of these compounds in dust collected from 10 houses, 38 apartments, 10 day care centers, 10 offices, and 5 cars. Samples were prepared using a rapid extraction and cleanup method and analyzed using LC-MS/MS. PFOS and PFOA were found in dust samples from all microenvironments and their concentrations were significantly positively correlated to each other. Highest median concentrations were seen in offices (PFOS: 110 ng/g dry weight) and apartments (PFOA: 93 ng/g dw). Adult and toddler dust ingestion exposures were estimated and compared to dietary exposure data from Canada and Spain. Results show that diet is the most important exposure route, but in a worst case scenario, dust ingestion may also be significant.
Planetary boundaries: Exploring the safe operating space for humanity
2009. Johan Rockström (et al.). Ecology & Society 14 (2)Artikel
Polybrominated diphenyl ether congener patterns, hexabromocyclododecane, and brominated biphenyl 153 in eggs of peregrine falcons (Falco peregrinus) breeding in Sweden.
2009. Anna-Karin Johansson (et al.). Environmental Toxicology and Chemistry 28 (1), 9-17Artikel
Previous analyses of 52 peregrine falcon (Falco peregrinus) eggs collected from two wild and one captive population in Sweden 1987 through 1999 were complemented by including additional polybrominated diphenyl ether (PBDE) congeners (BDE-35, -183, -184, -185, -196, -197, -203, and -207). In addition, 31 eggs not previously analyzed for hexabromocyclododecane (HBCD) and BDE-209 were analyzed for these. Geometric mean concentrations of BPBDEs, HBCD, and the hexabrominated biphenyl (BB-153) were 3,100, 140, and 81 ng/g of lipid weight for the southern population; 2,500, 110, and 84 ng/g of lipid weight for the northern population; and 47, not detected, and 8 ng/g of lipid weight for the captive population. The BDE congener pattern was dominated by BDE-153, -99, and -100. The results were used to investigate whether a difference in PBDE congener pattern could be distinguished between the two wild populations of peregrine falcons due to different diets, as the southern population preys mainly on birds belonging to the terrestrial food chain while the northern population preys more on aquatic birds. A multivariate t-test showed a subtle but significant (p < 0.001) difference in PBDE congener pattern between the two populations. However, our hypothesis that higher-brominated congeners of PBDEs would be present to a greater extent in the terrestrial food chain was not supported by principal component analysis. The average brood size for individual females from the southern population decreased with increasing concentrations of IPBDE in the eggs (log-linear regression p < 0.01).
Brominated flame retardants and perfluorinated compounds in air and dust from apartment buildings in Stockholm
2008. Cynthia A. de Wit, Kaj Thuresson, Justina Björklund.Rapport
Brominated flame retardants and perfluorinated compounds in air and dust from indoor environments in Stockholm
2008. Cynthia A. de Wit, Kaj Thuresson, Justina Björklund.Rapport
Brominated flame retardants in sludge from 50 Swedish sewage treatment plants: Evidence of anaerobic degradation of HBCD and TBBPA.
2007. de Wit (et al.). Dioxin 2007, Tokyo, JapanKonferens
Brominated flame retardants in the Arctic – Trends, pathways and new candidates.
2007. D.C.G. Muir, M. Alaee, de Wit. Fourth International Worskhop on Brominated Flame Retardants BFR 2007, Amsterdam, the NetherlandsKonferens
Congener patterns of PBDEs in eggs from peregrine falcon (Falco peregrinus) breeding in Sweden.
2007. Anna-Karin Johansson (et al.). Fourth International Worskhop on Brominated Flame Retardants BFR 2007, Amsterdam, the NetherlandsKonferens
Environmental behavior of brominated POPs in aquatic and terrestrial ecosystems, particularly higher brominated PBDEs
2007. de Wit. SETAC North America, Milwaukee, WisconsinKonferens
Fate of Higher Brominated PBDEs in Lactating Cows
2007. Amelie Kierkegaard (et al.). Environ. Sci. Technol. 41, 417-423Artikel
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