Concentrations Of Polybrominated Diphenyl Ethers Congeners Research Articles

Serum polybrominated diphenyl ether exposure and influence factors in blood donors of Wuxi adults from 2013 to 2016

Polybrominated diphenyl ethers (PBDEs) have been used as brominated flame retardants worldwide and are correlated with extensive environmental pollution and human health concerns. This study is aimed at analyzing the concentrations of PBDEs and at evaluating their temporal trends among a population of blood donors (n = 33) over a 4-year period. A total of 132 serum samples were used for PBDE detection. Nine PBDE congeners were quantified in serum samples by gas chromatography with mass spectrometry (GC-MS). The median concentrations of Σ9PBDEs in each year were 33.46, 29.75, 30.85, and 35.02ng/g lipid, respectively. Most of the PBDE congeners showed a downward trend from 2013 to 2014 and then increased after 2014. No correlations between age and PBDE congener concentrations were observed, while concentrations of each congener and Σ9PBDE were nearly always lower in females than in males, especially in BDE-66, BDE-153, BDE-183, BDE-190, and Σ9PBDE. We also found that the intake of fish, fruit, and eggs in the daily diet was related to the exposure level of PBDEs. Our results suggest that, as deca-BDE is still produced and used in China, diet is an important exposure pathway for PBDEs, and follow-up studies will be required to improve our understanding of the behaviors of PBDE isomers in humans and the exposure levels.

Legacy Chemical Pollutants in House Dust of Homes of Pregnant African Americans in Atlanta.

We developed and applied a method for measuring selected persistent organic pollutants (POPs) (i.e., polybrominated diphenyl ethers (PBDEs), organochlorine pesticides, and polychlorinated biphenyls (PCBs)) in dust collected from pregnant African Americans (AAs) in Atlanta using isotope dilution gas chromatography-tandem mass spectrometry. Limits of quantification were ranged from 0.10 to 2.50 ng/g dust. NIST standard reference material measurements demonstrated the robustness of our method. Our accuracies ranged from 82 to 108%, relative standard deviations ranged from 2 to 16%, and extraction recoveries ranged from 76 to 102%. We measured POPs in dust collected from 34 homes of pregnant AAs participating in the Atlanta AA birth cohort study who were enrolled from 2016 to 2019. Concentrations of POPs were detected in all samples with the frequencies of detection ranging from 8 to 100%. Concentrations of PBDE congeners 99 and 47, p,p'-DDT, and PCB153 were detected at some of the highest concentrations with geometric means of 1270, 730, 63.4 and 240 ng/g, respectively. The ratio of DDT/DDE was quite large (~2.7) indicating that p,p'-DDT remains intact in homes for long periods of time. These data demonstrate that care should be taken to remediate POPs in indoor dust, especially in vulnerable, disparate segments of the population.

Development of a fate and transport model for biodegradation of PBDE congeners in sediments

Polybrominated diphenyl ethers (PBDEs) are a family where each congener possesses different physicochemical properties, persistence and/or toxicity. Biodegradation can selectively change the abundance of congeners. These warrant modeling of individual congeners by considering biodegradation pathways together with fate and transport (F&T) mechanisms. Accordingly, this study aims to develop a F&T model (Fate and Transport model for Hydrophobic Pollutants - FTHP) that integrates congener specific biodegradation of PBDEs in sediments. The model is tested using sediment data from a location representing the Lower South Bay of San Francisco. Results demonstrated settling, resuspension, and biodegradation as important mechanisms. FTHP is then used to predict congener concentrations in a period of 20 years for two cases (constant and time-dependent water column concentrations) and four alternative scenarios: no intervention (i.e., natural attenuation, also serves as the base case), no degradation, dredging and biostimulation. The greatest impact on the reduction of total PBDE concentrations was achieved by a reduction in water column concentrations, i.e. source control, and dredging. On the other hand, biostimulation coupled with source control was the most effective in reducing bioaccumulative PBDE congener concentrations and almost as effective as dredging for the rest of congeners. Proposed FTHP model can distinguish between congeners and help devise informed management plans which focus on decreasing risks associated with persistent and bioaccumulative compounds in contaminated sediments.

Assessment of selected chlorinated and brominated flame retardants in human plasma samples among co-residing family members

Three hexachloronorbornene-based flame retardants and five polybrominated diphenyl ethers (PBDEs) were measured in 414 human plasma samples, (169 from children, 167 from mothers, and 78 from fathers), collected from 200 families between 2014 and 2016. The median concentration of ∑PBDEs (sum of BDE-47, -99, −100, −153 and −183) was 13.2 ng/g lipid for child, 9.03 ng/g lipid for mother and 12.7 ng/g lipid for father, respectively. Among the hexachloronorbornene-based flame retardants, Dec 602 was the most frequently detected chemical. Significant and positive correlations between the concentrations of PBDE congeners as well as between Dec 602 and Dec 603 were observed. Concentrations of PBDE congeners also showed significant and positive correlations in paired samples from family members (child-mother-father), while Dec 602 was the only hexachloronorbornene-based flame retardant whose concentrations correlated between family members, and only in mother-father paired samples. This is the largest study to date focusing on measuring and correlating HRFs in children and their parents living in the same household. The results convey important information on human exposure to measured HFRs, which can help researchers and regulators more clearly understand the influence of diet and the home environment.

Study on arbor leaf and ring as a potential biological indicator for atmospheric polybrominated diphenyl ethers (PBDEs) distribution at e-wastes recycling sites

Polybrominated diphenyl ethers (PBDEs) are considered to be the main pollutants at e-wastes recycling sites (EWRSs). Exploring the excellent and efficient bio-indicators of atmospheric PBDEs is attracting the more and more researchers to aforementioned direction in all over the globe. Arbor leaf and air samples were collected in four EWRSs located in Taizhou city, Zhejiang province of China, and PBDEs concentrations in local atmosphere at four sampling sites generally followed a trend as follows: Mukengcun (1940.83–18,545.12 ng/g) > Yanggongao (1017.56–7740.93 ng/g) > Wenqiaozhen (420.47–3146.9 ng/g) > Changyudongtian (36.39–69.54 ng/g). The accumulated contents of absorbing the atmospheric PBDEs in eight arbor species were observed by the following trend: Magnoliagrandiflora > Ilexchinensis > Cinnamomumcamphora > Cedardeodara > Sabinachinensis > Cunninghamialanceolata > Metasequoiaglyptostroboides > Salixbabylonica. BDE47, BDE99, and BDE209 were evaluated as the main PBDEs congeners. Additionally, ∑PBDEs accumulation showed the increasing trend with leaf age and lipid content. The concentrations of PBDEs congeners in arbor leaf/ring at four sampling sites also indicated the good relationship in atmospheric gas phase, fine particulate matter (PM2.5), and total suspended particulate. The coefficients of correlations were determined in the range of 0.957–0.999. On the other hand, the sampling height and tree age were not observed as an ideal indicator. Moreover, the longitudinal distribution of PBDEs showed a little difference, while its radial distribution seemed to be fluctuated during the growth period. We believe that our conducted research will open up the new avenues about the remediation of PBDEs contents and its derivatives from the atmosphere by using the arbor leaf and ring as a biological indicator at EWRSs.

Halogenated flame retardants and organophosphate esters in the air of electronic waste recycling facilities: Evidence of high concentrations and multiple exposures

BackgroundIn response to a worldwide increase in production of electronic waste, the e-recycling industry is rapidly rowing. E-recycling workers are exposed to many potentially toxic contaminants, among which flame retardants (FRs), mainly suspected of being endocrine disruptors, are thought to be the most prevalent. ObjectiveTo conduct an exposure assessment of four chemical groups of FRs in Canadian e-recycling facilities, and to identify the main cofactors of exposure. MethodsPersonal air samples were collected over a workday for 85 workers in six e-recycling facilities, grouped into three facility sizes, and for 15 workers in control commercial waste facilities. Total particulate matter was measured by gravimetry with stationary air samples. FRs were collected on OSHA versatile samplers, which allow particulate and vapor phases collection. Fifteen polybrominated diphenyl ether congeners (PBDEs), nine novel brominated (NBFRs), two chlorinated (ClFRs), and fourteen organophosphate ester (OPEs) flame retardants were analysed by gas chromatography–mass spectrometry. Sociodemographic data, tasks performed and materials processed by participating workers were recorded. Tobit regressions were used to identify cofactors of exposure, and their conclusions were corroborated using semi-parametric reverse Cox regressions. ResultsThirty-nine of the 40 FRs analysed were detected in at least one air sample in e-recycling, and workers in this industry were exposed on average to 26 (range 12 to 39) different substances. The most detected chemical group of FRs in e-recycling was PBDEs with geometric mean sums of all congeners ranging from 120 to 5100 ng/m3, followed by OPEs with 740 to 1000 ng/m3, NBFRs with 7.6 to 100 ng/m3, and finally ClFRs with 3.9 to 32 mg/m3. The most important cofactor of exposure was the size of the e-recycling facility, with the largest one presenting on average 12 times the concentrations found in the control facility. Among tasks as potential cofactors of exposure, manual dismantling and baler operation exposed workers to some of the highest concentrations of PBDEs and ClFRs. There was a reduction of up to 27% in exposure to FRs associated with a 3-year increase in seniority. Finally, particulate matter concentrations in e-recycling facilities were highly correlated with all chemical classes except OPEs, and were higher in the large facility. ConclusionsAmong the FRs analysed, PBDE exposure was particularly high in e-recycling. Dust and particulate matter reduction strategies in these workplaces, together with training on proper working practices would certainly be important first steps to lower occupational exposures and prevent potential health effects.

Current halogenated flame retardant concentrations in serum from residents of Shandong Province, China, and temporal changes in the concentrations

The residents of Shandong Province, China, are exposed to high concentrations of halogenated flame retardants because large amounts of halogenated flame retardants are produced in the province. We determined the concentrations of eight polybrominated diphenyl ether congeners (PBDEs), seven novel brominated flame retardants (NBFRs), and the two dechlorane plus isomers (DPs) in serum from residents of Shandong Province. The aim was to identify temporal trends in the concentrations of these pollutants. The mean total concentrations of PBDEs, NBFRs and DPs were 41, 2.2 and 2.1ng/g lipid in pooled serum samples collected in 2014, and were 32, 3.5 and 3.1ng/g lipid in pooled serum samples collected in 2015, respectively. Decabromodiphenyl ether was the dominant PBDE congener in all of the samples. The novel brominated flame retardant and dechlorane plus concentrations were between one and two orders of magnitude lower than the PBDE concentrations. The PBDE concentrations in serum decreased significantly between 2007 and 2015, but the pentabromobenzene, pentabromotoluene, and dechlorane plus concentrations were relatively stable.

Distribution of Polybrominated Diphenyl Ethers in Sewage Sludge, Sediments, and Fish from Latvia

The polybrominated diphenyl ethers (PBDEs) are bioaccumulative, persistent, and toxic. They have a high risk of emission into the environment via volatile losses and diffuse sources, such as commercial product disposal or the use of sewage sludge. The PBDEs’ congeners were analyzed in municipal waste water treatment plant (WWTP) sludge, river and lake water, sediment, and fish samples, to investigate the concentrations in urban and natural locations. The sum of eight PBDE congener (∑8PBDE 28, 47, 99, 100, 153, 154, 183, 209) concentrations in WWTP sludge varied from 78 ng·g−1 DW, to 714 ng·g−1 DW. The BDE 209 constituted up to 93%–98% of ∑8PBDE. In water, the concentrations of all of the measured PBDE congeners were below the limit of detection. Similarly, the concentration of BDE 209 in the sediments was below the limit of detection in all samples. The sum of seven PBDE congener concentrations in the sediments varied from 0.01 to 0.13 ng·g−1 DW. The sum of eight PBDE congener concentrations in fish (European perch) tissues varied from 0.13 to 0.82 ng·g−1 WW. As was recorded for the WWTP sludge, the BDE 209 was the dominant congener, constituting 24%–93% of ∑8PBDE. The sum of seven PBDE congener concentrations, excluding BDE 209, as well as the concentrations of BDE 209 that were measured in WWTP sludge, exhibited a weak negative correlation (Pearson’s r = −0.56, p = 0.1509 and r = −0.48, p = 0.2256, respectively) with the content of dry matter in the sludge. The sum of seven PBDE congener concentrations measured in sediments exhibited a strong negative correlation (Pearson’s r = −0.82, p = 0.0006) with the content of dry matter in the sediments, and a strong positive correlation (Pearson’s r = 0.68, p = 0.0109) with the total carbon content. The obtained results indicated that the fine-grained WWTP sludge particles, with a larger relative surface area, adsorbed BDE 209 the most effectively. This finding was supported by the relatively low environmental concentrations of PBDE congeners, especially BDE 209, which can be explained by the lack of using sewage sludge in agricultural application in Latvia. Furthermore, it seems that, at present, the observed differences in the PBDE congener concentrations in sediments can be attributed to differences in the physical-chemical properties of sediments.

Bioconcentration of polybrominated diphenyl ethers and organochlorine pesticides in algae is an important contaminant route to higher trophic levels.

Persistent organic pollutants (POPs) present in water may be bioconcentrated in phytoplankton and further transferred into higher trophic levels. In the present study, seawater, sediment, phytoplankton and macroalgae (Ulva lactuca L.) samples were collected from two estuarine bays in South China and analyzed for 24 polybrominated diphenyl ethers (PBDEs) and 22 organochlorine pesticides (OCPs). The concentrations of PBDE congeners except BDE-209 were low in both phytoplankton and Ulva. BDE-209 was the predominant congener in phytoplankton and Ulva, accounting for 89.5% and 86.6% of the total average concentrations of PBDEs (48.5 and 4.1ngg-1dw), respectively. The average concentrations of DDTs, HCHs and 1-chloro-2,2-bis(4-chlorophenyl)ethane (p,p'-DDMU) in phytoplankton were 398, 241 and 11.3ngg-1dw, respectively, while those of DDTs and HCHs in Ulva were 8.4 and 33.1ngg-1dw. The levels of both PBDEs and OCPs were an order of magnitude higher in phytoplankton than in Ulva, indicating that phytoplankton with larger surface areas have higher uptake efficiency for POPs than Ulva. Bioconcentration factors (BCFs) of DDT and PBDE in phytoplankton from the two bays were in the range of 105-106, suggesting that bioconcentration may be one of the key sources of POPs and algae can be an important route for POPs to move toward higher trophic levels.

The environmental fate of polybrominated diphenyl ethers (PBDEs) in western Taiwan and coastal waters: evaluation with a fugacity-based model.

The environmental fate of polybrominated diphenyl ethers (PBDEs), a group of flame retardants that are considered to be persistent organic pollutants (POPs), around the Zhuoshui River and Changhua County regions of Taiwan was assessed. An investigation into emissions, partitioning, and fate of selected PBDEs was conducted based on the equilibrium constant (EQC) fugacity model developed at Trent University, Canada. Emissions for congeners PBDE 47, PBDE 99, and PBDE 209 to air (4.9–92 × 10−3 kg/h), soil (0.91–17.4 × 10−3 kg/h), and water (0.21–4.04 × 10−3 kg/h), were estimated by modifying previous models on PBDE emission rates by considering both industrial and domestic rates. It was found that fugacity modeling can give a reasonable estimation of the behavior, partitioning, and concentrations of PBDE congeners in and around Taiwan. Results indicate that PBDE congeners have a high affinity for partitioning into sediments then soils. As congener number decreases, the PBDEs then partition more readily into air. As the degree of bromination increases, congeners more readily partition to sediments. Sediments may then act as a long-term source of PBDEs which can be released back into the water column due to resuspension during storm events.Electronic supplementary materialThe online version of this article (doi:10.1007/s11356-016-6428-4) contains supplementary material, which is available to authorized users.

Factors influencing atmospheric concentrations of polybrominated diphenyl ethers in Japan.

We used polybrominated diphenyl ether (PBDE) data in air at 38 sites across Japan (2009-2012), which were measured by the Japan Ministry of Environment (JMOE), to elucidate the time trend and seasonality of atmospheric PBDEs. In order to address few (7% for BDE-47) to many (63% for BDE-153 and 183) non-detect data, Tobit model, also called a censored regression model was used. The model revealed that the concentrations of PBDE congeners were influenced by a combination of year, temperature, rainfall rate, and population density. Greater declines were observed for BDE-47, -99, -153 and -183 (-21, -25, -17, -23%/year, p < 0.05) than for BDE-209 (-6%/year, p = 0.065). These trends were consistent with the estimated trends of penta-, octa- and deca-BDE contained in in-use products based on domestic demand for PBDEs in Japan and product lifespan. Seasonal patterns were opposite for light congeners (BDE-47 and -99), which increased with temperature, and heavy congeners (BDE-183, and -209), which decreased with temperature. Temperature-dependent emission (evaporation) for light congeners and temperature-independent emission (abrasion) for heavy congeners, coupled with seasonality of atmospheric boundary layer height, might explain these seasonal patterns. Human population density showed a positive correlation with all PBDE congener concentrations, whereas PBDEs showed negative correlation with rainfall rate.

Distribution of polybrominated diphenyl ethers and dust particle size fractions adherent to skin in indoor dust, Pretoria, South Africa

In order to determine human exposure to the indoor toxicant, selection of dust fraction and understanding dust particle size distribution in settled indoor dust are very important. This study examined the influence of dust particle size on the concentration of polybrominated diphenyl ethers (PBDEs) congeners, assessed the distribution of dust particle size and characterized the main indoor emission sources of PBDEs. Accordingly, the concentrations of PBDE congeners determined in different indoor dust fractions were found to be relatively higher in the order of dust particle size: 45-106 μm>(<45 μm)>106-150 μm. The finding shows arbitrary selection of dust fractions for exposure determination may result in wrong conclusions. Statistically significant moderate correlation between the concentration of Σ9PBDEs and organic matter content calculated with respect to the total dust mass was also observed (r=0.55, p=0.001). On average, of total dust particle size <250 μm, 93.4 % (m/m%) of dust fractions was associated with less than 150 μm. Furthermore, of skin adherent dust fractions considered (<150 μm), 86 % (v/v%) is in the range of particle size 9.25-104.7 μm. Electronic materials treated with PBDEs were found the main emission sources of PBDE congeners in indoor environment. Based on concentrations of PBDEs determined and mass of indoor dust observed, 150 μm metallic sieve is adequate for human exposure risk assessment. However, research in this area is very limited and more research is required to generalize the fact.

Concentrations and congener profiles of polybrominated diphenyl ethers (PBDEs) in blood plasma from Hong Kong: Implications for sources and exposure route

There was limited information about bioaccumulation of polybrominated diphenyl ethers (PBDEs) in humans of the general population of Hong Kong. Therefore, the present study was conducted to determine concentrations and congener profiles of PBDEs in blood plasma from Hong Kong, evaluate their sources and correlations with other organobrominated compounds, and investigate exposure routes from fish and dust. Concentrations of ∑PBDE22 ranged from 0.56 to 92ngg−1, lipid weight (lw), with a median of 5.4ngg−1. BDE-47 was the dominant congener, accounting for 26% of ∑PBDE22. Concentrations of PBDE congeners in market fish were significantly (r2=0.89, p<0.001) correlated with plasma. Positive but no significant correlations were observed, between concentrations of PBDE congeners in indoor dust from workplaces (r2=0.46, p=0.081) and homes (r2=0.49, p=0.10), with concentrations of PBDE in human blood plasma. The results indicated that dietary exposure, particularly consumption of fish, is a major pathway through which people in Hong Kong are exposed to PBDEs. Furthermore, our data revealed a spatial distribution and terrestrial source of BDE-28 for local people. Results of the present study, which was the first systematic study to investigate concentrations of PBDEs in blood of Hong Kong people, provides useful information to which future measurements can be compared.

Polybrominated diphenyl ethers (PBDEs) in the surface sediments and suspended particulate matter (SPM) from Lake Chaohu, a large shallow Chinese lake

Suspended particulate matter (SPM) and surface sediment samples were collected from Lake Chaohu to investigate the residues, congener profile, and spatial distribution of polybrominated diphenyl ethers (PBDEs) in a large shadow lake in the middle of the Yangtze River Basin. The concentration of Σ13BDEs (defined as the sum of 13 target congeners excluding BDE 209) and the concentration of BDE 209 ranged from 236.7 to 1373.4pg/g dry weight (dw) and from 4.2 to 691.2pg/g dw in the surface sediments, respectively, which were 2–3 orders of magnitude smaller than those found in the SPM. The congener composition was dominated by BDE 47 (50.8%) and BDE 209 (21.3%) in the sediment, while the proportion of BDE 47 to Σ14BDEs in the SPM was slightly higher than that in the sediment. The concentration of Σ14BDEs in the sediment from the drinking water source (WR) area in the eastern part of the lake was very low, with a mean value of 514.8pg/g, whereas the mean concentration was 102.4ng/g in the SPM. A cluster analysis (CA) was conducted to further illustrate the dominance of each congener and the similarity of each sampling site. Many factors, including resuspension, photodecomposition, microbial oxidation, local discharge, and dredging, influenced the distribution in the sediment and SPM for the PBDE congeners as well as the spatial distribution of PBDEs. A formula for the PBDE concentrations in the surface sediment and SPM was constructed to understand the potential relationship between sediment and SPM concentrations. Although the formula did not accurately predict specific PBDE congener concentrations in the sediment, it remains a practical and useful way to assess the overall pollution of PBDE in sediment in Lake Chaohu, as it depends only on the concentrations of PBDEs in the SPM.

Occurrence of brominated flame retardants in household and car dust from the Czech Republic

The levels and profiles of 16 polybrominated diphenyl ethers congeners (PBDEs), three isomers of hexabromocyclododecane (HBCD) and other six “alternative” brominated flame retardants (BFRs) in dust collected in 25 Czech households and 27 car interiors were investigated. The Σ16 PBDEs contents varied widely with maximum concentrations reaching up to 5896 and 33728μg/kg in house and car dust, respectively. The highest concentrations of PBDEs were observed for BDE 209, which was found almost in all samples and exceeded concentrations of other PBDEs even by one order of magnitude. The profile and levels of Penta-, Octa-, and DecaBDE obtained within this study were comparable to those presented in other studies worldwide and confirmed lower contamination of dust from Europe compared to North America. From the group of “alternative” BFRs, suitable for commercial applications as an alternative to banned PBDEs, mainly decabromodiphenyl ethane (DBDPE) and HBCD were detected in the concentration ranges <20–3567 and <0.3–950μg/kg, respectively. γ-HBCD was dominating, forming up to 70% of ΣHBCD. Using the measured concentrations and estimates of dust ingestion rates it was estimated that toddlers had a higher exposure than adults for all compounds investigated.

Distribution of polybrominated diphenyl ethers in Japanese autopsy tissue and body fluid samples

Brominated flame retardants are components of many plastics and are used in products such as cars, textiles, televisions, and personal computers. Human exposure to polybrominated diphenyl ether (PBDE) flame retardants has increased exponentially during the last three decades. Our objective was to measure the body burden and distribution of PBDEs and to determine the concentrations of the predominant PBDE congeners in samples of liver, bile, adipose tissue, and blood obtained from Japanese autopsy cases. Tissues and body fluids obtained from 20 autopsy cases were analyzed. The levels of 25 PBDE congeners, ranging from tri- to hexa-BDEs, were assessed. The geometric means of the sum of the concentrations of PBDE congeners having detection frequencies >50 % (ΣPBDE) in the blood, liver, bile, and adipose tissue were 2.4, 2.6, 1.4, and 4.3 ng/g lipid, respectively. The most abundant congeners were BDE-47 and BDE-153, followed by BDE-100, BDE-99, and BDE-28+33. These concentrations of PBDE congeners were similar to other reports of human exposure in Japan but were notably lower than concentrations than those reported in the USA. Significant positive correlations were observed between the concentrations of predominant congeners and ΣPBDE among the samples analyzed. The ΣPBDE concentration was highest in the adipose tissue, but PBDEs were distributed widely among the tissues and body fluids analyzed. The PBDE levels observed in the present study are similar to those reported in previous studies in Japan and significantly lower than those reported in the USA.

Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and neuropsychological status among older adults in New York

Polybrominated diphenyl ethers (PBDEs) are emerging environmental contaminants, but little is known about their possible human health effects. The objective of this study is to evaluate the association between exposure to PBDEs and neuropsychological function among older adults and the possibility of effect modification with polychlorinated biphenyls (PCBs). Serum samples were analyzed for concentrations of 9 PBDE and 30 PCB congeners and 34 tests of cognitive and motor function, affective state, and olfactory function were assessed among 144 men and women of 55–74 years of age. After adjustment for relevant confounders, no overall associations were observed between the sum of the PBDE congener concentrations in serum (∑ PBDE) and scores on the neuropsychological tests. However, statistically significant interactions were found between PBDEs and PCBs for some measures of verbal learning and memory. Among persons with ∑ PCB concentrations at or above the median of 467ppb (lipid basis), an increase in ∑ PBDE concentrations from the 25th to 75th percentile was associated with decreases between 7% and 12% on scores for certain subscales of the California Verbal Learning Test. In contrast, no statistically significant associations were observed for PBDEs among persons with ∑ PCB levels below the median. The results suggest that PBDEs and PCBs may interact to affect verbal memory and learning among persons 55–74 years old. This is the first study to evaluate the neuropsychological effects of PBDEs in adults and the possibility of synergy with PCBs in humans.

FETAL EXPOSURE TO POLYBROMINATED DIPHENYL ETHERS (PBDES) AND ATOPIC DERMATITIS IN INFANTS

Background and Aims: Polybrominated diphenyl ether (PBDE) is one of the brominated flame retardants. Some of the PBDE congeners or isomers are reported to have high toxicity and endocrine disrupting effects. The health effects of PBDEs have been reported to be different among the congeners and isomers. Our previous studies revealed that Japanese fetuses were exposed to PBDEs. In Japan, the number of allergic disease patients is rapidly increasing among children. To find the reason of this rapid increase, an association between the occurrence of atopic dermatitis (AD) among the infants and the fetal exposure to PBDE congeners and isomers was examined. Methods: One hundred and thirteen umbilical cords (UC) were collected in Chiba City (Japan) at deliveries. The concentrations of PBDE congeners and isomers in the 55 UC was measured by GC/MS. Medical doctor’s diagnosis in follow-up study showed that 18 infants were AD and 37 infants were non-AD at 7-months old. This study was approved by the “Congress of Medical Bioethics” of Chiba University and all the samples were obtained after receipt of written informed consent. Results: We found significant correlation between the occurrence of AD and the concentration of total PBDEs (t&lt;0.05), TriBDE (t&lt;0.05), TetraBDE (t&lt;0.01), PentaBDE (t&lt;0.01) and PentaBDE #99 (t&lt;0.05). Our findings indicate that there are strong or weak association between some congeners and isomers of PBDEs and the occurrence of AD in infants. Conclusions: Our present data suggest the possibility that there is some association between fetal exposure to PBDEs and the occurrence of AD among infants. However, it is unclear if the association is due to combined effects of PBDEs and other chemicals or due to the fetal exposure or exposure though breast milk. We need further studies to clarify this association.

Prenatal Exposure to PBDEs and Neurodevelopment

BackgroundPolybrominated diphenyl ethers (PBDEs) are widely used flame retardant compounds that are persistent and bioaccumulative and therefore have become ubiquitous environment contaminants. Animal studies suggest that prenatal PBDE exposure may result in adverse neurodevelopmental effects.ObjectiveIn a longitudinal cohort initiated after 11 September 2001, including 329 mothers who delivered in one of three hospitals in lower Manhattan, New York, we examined prenatal PBDE exposure and neurodevelopment when their children were 12–48 and 72 months of age.MethodsWe analyzed 210 cord blood specimens for selected PBDE congeners and assessed neurodevelopmental effects in the children at 12–48 and 72 months of age; 118, 117, 114, 104, and 96 children with available cord PBDE measurements were assessed at 12, 24, 36, 48, and 72 months, respectively. We used multivariate regression analyses to evaluate the associations between concentrations of individual PBDE congeners and neurodevelopmental indices.ResultsMedian cord blood concentrations of PBDE congeners 47, 99, and 100 were 11.2, 3.2, and 1.4 ng/g lipid, respectively. After adjustment for potential confounders, children with higher concentrations of BDEs 47, 99, or 100 scored lower on tests of mental and physical development at 12–48 and 72 months. Associations were significant for 12-month Psychomotor Development Index (BDE-47), 24-month Mental Development Index (MDI) (BDE-47, 99, and 100), 36-month MDI (BDE-100), 48-month full-scale and verbal IQ (BDE-47, 99, and 100) and performance IQ (BDE-100), and 72-month performance IQ (BDE-100).ConclusionsThis epidemiologic study demonstrates neurodevelopmental effects in relation to cord blood PBDE concentrations. Confirmation is needed in other longitudinal studies.

Perfluorinated Compounds and Polybrominated Diphenyl Ethers in Great Blue Heron Eggs from Three Colonies on the Mississippi River, Minnesota

Archived Great Blue Heron (Ardea herodias) eggs (N = 16) collected in 1993 from three colonies on the Mississippi River in Minnesota were analyzed in 2007 for perfluorinated compounds (PFCs) and polybrominated diphenyl ethers (PBDEs). One of the three colonies, Pig's Eye, was located near a presumed source of PFCs. Based on a multivariate analysis, the pattern of nine PFC concentrations differed significantly between Pig's Eye and the upriver (P = 0.002) and downriver (P = 0.02) colonies; but not between the upriver and downriver colonies (P = 0.25). Mean concentrations of perfluorooctane sulfonate (PFOS), a major PFC compound, were significantly higher at the Pig's Eye colony (geometric mean = 940 ng/g wet weight) than at upriver (60 ng/g wet weight) and downriver (131 ng/g wet weight) colonies. Perfluorooctane sulfonate concentrations from the Pig's Eye colony are among the highest reported in bird eggs. Concentrations of PFOS in Great Blue Heron eggs from Pig's Eye were well below the toxicity thresholds estimated for Bobwhite Quail (Colinus virginianus) and Mallards (Anas platyrhynchos), but within the toxicity threshold estimated for White Leghorn Chickens (Gallus domesticus). The pattern of six PBDE congener concentrations did not differ among the three colonies (P = 0.08). Total PBDE concentrations, however, were significantly greater (P = 0.03) at Pig's Eye (geometric mean = 142 ng/g wet weight) than the upriver colony (13 ng/g wet weight). Polybrominated diphenyl ether concentrations in two of six Great Blue Heron eggs from the Pig's Eye colony were within levels associated with altered reproductive behavior in American Kestrels (Falco sparverius).