Polybrominated diphenyl ethers and polychlorinated biphenyls in a marine foodweb of coastal Florida

Nine species of marine fish, including teleost fishes, sharks, and stingrays, and two species of marine mammals (dolphins) collected from Florida coastal waters were analyzed for polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) to evaluate biomagnification factors (BMF) of these contaminants in a coastal foodweb. In addition, bottlenose dolphins and bull sharks collected from the Florida coast during the 1990s and the 2000s were analyzed for evaluation of temporal trends in PBDE and PCB levels in coastal ecosystems. Mean concentrations of PBDEs in muscle tissues of teleost fishes ranged from 8.0 ng/g, lipid wt (in silver perch), to 88 ng/g, lipid wt (in hardhead catfish), with an overall mean concentration of 43 +/- 30 ng/g, lipid wt. Mean concentrations of PBDEs in muscle of sharks ranged from 37.8 ng/g, lipid wt, in spiny dogfish to 1630 ng/g, lipid wt, in bull sharks. Mean concentrations of PBDEs in the blubber of bottlenose dolphins and striped dolphins were 1190 +/- 1580 and 660 ng/g, lipid wt, respectively. Tetra-BDE 47 (2,2',4,4'-) was the major congener detected in teleost fishes and dolphin samples, followed by BDE-99, BDE-153, BDE-100, and BDE-154. In contrast, BDE-209 was the most abundant congener in sharks. Concentrations of PBDEs and PCBs in dolphins and sharks were 1-2 orders of magnitude greater than those in lower trophic-level fish species, indicating biomagnification of both of these contaminants in the marine foodweb. Based on the analysis of sharks and dolphins collected over a 10-year period, an exponential increase in the concentrations of PBDEs and PCBs has occurred in these marine predators. The doubling time of PBDE and PCB concentrations was estimated to be 2-3 years for bull sharks and 3-4 years for bottlenose dolphin.     

Polybrominated dibenzo-p-dioxins,dibenzofurans, and diphenyl ethers in Japanese human adipose tissue

Human adipose samples collected in Tokyo, Japan in 1970 and 2000 were analyzed for the presence of polybrominated dibenzo-p-dioxins (PBDDs), dibenzofurans (PBDFs), and diphenyl ethers (PBDEs), and the concentrations in the two groups were compared. As far as we know, the concentrations of the PBDD/Fs in adipose tissue from the general Japanese population are reported for the first time. Three PBDD/F congeners were found in the following adipose tissues: 2,3,7,8-TeBDD, 2,3,7,8-TeBDF, and 2,3,4,7,8-PeBDF. The median concentrations (ranges) of three PBDD/Fs in 1970 and 2000 were 5.1 (3.4-8.3) and 3.4 (1.9-5.3) pg/g lipid wt (l.w.), respectively. For PBDEs, seven PBDE congeners were determined in the following samples: 2,4,4'-tribromodiphenyl ether (BDE-28), 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), 2,2',4,4',5-pentabromodiphenyl ether (BDE-99), 2,2',4,4',6-pentabromodiphenyl ether (BDE-100), 2,2',4,4',5,5'-hexabromodiphenyl ether (BDE-153), 2,2',4,4',5',6-hexabromodiphenyl ether (BDE-154), and 2,2',3,4,4',5',6-heptabromodiphenyl ether (BDE-183). Median concentrations (ranges) of PBDEs showed a significant increase from 29.2 (6.8-78.4) pg/g l.w. in 1970 to 1288 (466-2,753) pg/g l.w. in 2000. BDE-47, the major congener of PBDEs, was 56.2% and 35.6% of the total in 1970 and 2000, respectively, whereas the BDE-153 was < 1% and 29.7% of the total in 1970 and 2000, respectively. This may indicate that the source of PBDEs had changed during this period. Further analysis of archived human samples from 1970 to 2000 is needed to describe the details of the contamination trends of PBDD/Fs and PBDEs in the Japanese population. Furthermore, PBDD/F monitoring, particularly 2,3,7,8-TeBDD and 2,3,7,8-TeBDF, may give more toxicological information based on TeCDD toxic equivalents (TEQs).     

Brominated flame retardants in serum from U.S. blood donors

Serum samples collected in 1988 from U.S. blood donors were analyzed for polybrominated diphenyl ethers (PBDEs) and polychlorinated and polybrominated biphenyls (PCBs and PBBs). The levels of the PBDEs are reported for the first time in serum from the U.S. population. The median concentrations and range of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47); 2,2',4,4',5,5'-hexabromodiphenyl ether (BDE-153); 2,2',3,4,4',5',6-heptabromodiphenyl ether (BDE-183); and decabromodiphenyl ether (BDE-209) were 1.3 (<0.8-49); 0.54 (0.13-3.1); 0.24 (0.12-1.8); and <1 (<1-35) pmol/g lipid weight (l.w.), respectively. In addition we also measured detectable levels of nine additional PBDE congeners in many of the serum samples. The median concentrations and ranges of 2,2',4,4',5,5'-hexachloro- and hexabromobiphenyl (CB-153 and BB-153) were 190 (21-2600) and 19 (4.2-84) pmol/g l.w. The levels of PBDEs and CB-153 found in the U.S. samples were similar to background levels reported in the serum of Swedish hospital cleaners collected 10 years later, i.e., 1997. The BB-153 congener measured in the U.S. samples was not found in the Swedish samples. The difference in exposure to this congener could not be assessed in this study, although might be related to the 1973 BB-153 (FireMaster BP-6) animal and human contamination incident in the State of Michigan.     

Comparison of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in Lake Michigan salmonids

Polybrominated diphenyl ethers (PBDEs) have been used extensively over the past two decades as flame retardants in most types of polymers. Many measurements of PBDEs in various environmental matrices from Sweden, Holland, Japan, and elsewhere have been reported, but few measurements are available for North America. PBDEs in 21 coho and chinook salmon taken from Lake Michigan tributaries in 1996 were measured for this study. The salmon samples were extracted and initially analyzed for polychlorinated biphenyl (PCB) congeners. It was demonstrated for these samples that the same extract fraction contains PBDEs. Six PBDE congeners were observed in all 21 samples, and the rank order of concentration of these congeners was similar to that in commercial mixtures of PBDEs. The average concentration across all samples of the sum of PBDE congeners was 80.1 ng/g of wet weight or 2,440 ng/g of lipid. This is much less than the average sum PCB concentration (1,450 ng/g of wet weight; 43,100 ng/g of lipid). However, the average concentration of the most abundant PBDE congener (IUPAC BDE-49: 52.1 ng/g wet, 1,590 ng/g of lipid) was about one-third of the average concentration of the most abundant PCB congener (IUPAC CB-153: 149 ng/g wet, 4,550 ng/g of lipid). On the basis of an extensive literature survey, the concentrations of PBDEs reported here are among the highest in the world for salmon in open waters. The concentrations of PBDEs and PCBs are both correlated with fish length and mass, but not with lipid content. The concentrations of PBDEs and PCBs are highly correlated in individual fish, implying that PBDEs are as prevalent as PCBs in Lake Michigan.     

Polybrominated diphenyl ethers contamination of United States food

Elevated levels of polybrominated diphenyl ethers (PBDEs), a type of brominated flame retardant, were recently detected in U.S. nursing mothers' milk. These halogenated compounds chemically and toxicologically resemble others such as polychlorinated biphenyls (PCBs), whose route of intake is almost exclusively through food of animal origin. This study is the first to report the levels of PBDEs in U.S. foods in a market basket survey of 30 food types (total of 32 food samples) from three major supermarket chains in Dallas, TX. Food samples were almost exclusively foods of animal origin: meat, fish, and dairy products. Thirteen PBDE congeners were measured for each sample. Levels were then compared to existing PBDE food studies from other countries where available. In this study, levels of PBDEs are highest in fish, then meat, and lowest in dairy products; median levels were 1725 (range 8.5-3078), 283 (range 0.9-679), and 31.5 (0.2-1373), parts per trillion (ppt), or pg/g, wet weight, respectively. Nonfat milk did not have any detectable PBDE levels. In fish, PBDE congener 47 (2,2',4,4'-tetraBDE) contributes up to 70% of the total PBDEs, followed by congeners 100 (2,2',4,4',6) and 99 (2,2',4,4',5). In meat congener 99 predominates, followed by 47. In dairy, BDE 47 predominates followed by 99. U.S. food PBDE levels measured in this study are higher than reported in two other published market based studies from Spain and Japan. Although these findings are preliminary and will be updated with analyses of new samples, they suggest that food is a major route of intake for PBDEs.     

Concentrations of polybrominated diphenyl ethers, polychlonnated biphenyls, and polychlorobiphenylols in serum from pregnant Faroese women and their children 7 years later

The objective of this study was to assess blood concentrations of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs), and their polychlorobiphenylol (OH-PCB) metabolites in humans with a high seafood intake. Samples were obtained from pregnant women in the Faroe Islands in 1994-1995 and from their children at 7 years of age to examine maternal transfer of the compounds to their child, age-dependent metabolism, and temporal changes. Maternal serum was dominated by 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), while 2,2',4,4',5,5'-hexabromodiphenyl ether (BDE-153) prevailed in the children's serum seven years later. DecaBDE was present in both mothers and children up to 3 and 6 ng/g lipid weight, respectively. The sigmaPCB concentration in the children averaged about 60% of the concentrations in their mothers, with median levels for both above 1 microg/g lipid weight and .with similar PCB congener patterns. sigmaOH-PCB serum concentrations from the mothers and their children showed ranges of 1.8-36 ng/g wet weight (ww) and 0.49-22 ng/g ww, respectively, with all OH-PCB congener concentrations being lower in the children, except for 2,3,3',4',5-pentachloro-4-biphenylol (4-OH-CB107). Children at 7 years of age are exposed to PCBs at levels only slightly below those of their mothers, and the increased 4-OH-CB107 concentrations in children could be due to age-related differences in PCB metabolism. The PBDE concentrations were similar in both mothers and their children. The main persistent organic pollutant concentrations in the children are most probably due to other environmental exposure than maternal transfer.     

Debromination of polybrominated diphenyl ether congeners BDE 99 and BDE 183 in the intestinal tract of the common carp (Cyprinus carpio)

Polybrominated diphenyl ether (PBDE) congener patterns in biota are often enriched in tetra-, penta-, and hexabrominated diphenyl ethers, which is believed to result from the use of the commercial "pentaBDE" formulation. However, our evidence suggests that debromination of PBDEs occurs within fish tissues leading to appreciable accumulation of less brominated congeners. This suggests that PBDE body burdens can reflect both direct uptake from exposure and debromination of more highly brominated congeners. We conducted two independent dietary exposure studies using the common carp (Cyprinus carpio) to trace the fate of 2,2',4,4',5-pentabromodiphenyl ether (BDE 99) and 2,2',3,4,4',5',6-heptabromodiphenyl ether (BDE 183) in fish tissues. Carp were fed food spiked with individual BDE congeners for 62 d, and depuration was monitored during the following 37 d. Significant debromination was observed, converting BDE 99 to 2,2',4,4'-tetrabromodiphenyl ether (BDE47) and BDE 183 to 2,2',4,4',5,6-hexabromodiphenyl ether (BDE 154) and another as yet unidentified hexa-BDE congener. The BDE 99 concentration rapidly declined from 400 +/- 40 ng/g ww in the food to 53 +/- 12 ng/g ww in the gut content material sampled 2.5 +/- 1 h following feeding. At least 9.5 +/- 0.8% of the BDE 99 mass in the gut was debrominated to BDE 47 and assimilated in carp tissues. In the BDE 183 exposure, approximately 17% of the BDE 183 mass was debrominated and accumulated in carp tissues in the form of two hexa-BDE congeners. In both exposure studies, the concentration of the exposure compound decreased significantly in the gut within 2.5 +/- 1 h following ingestion. This rapid decrease in the concentration of the BDE congeners could not be explained entirely by debromination to quantified products or fecal egestion. Reactions occurring within the gut transform BDE congeners to other products that may accumulate or be excreted. Further studies are needed to identify and determine the effects of these BDE metabolites.     

A preliminary comparison of polybrominated diphenyl ether concentrations relative to lipid content and to levels of dioxins and dioxin-like polychlorinated biphenyls in Norwegian farmed Atlantic salmon (Salmo salar)

Polybrominated diphenyl ethers (PBDEs) are environmental contaminants structurally similar to polychlorinated biphenyls (PCBs), and correlations between PBDE concentrations and concentrations of lipid, PCBs, dioxins and furans in feed and farmed Atlantic salmon filet indicate PBDEs may be derived from similar sources. PBDE concentrations (3.9 ± 0.6 ng g^?1 wet wt) in farmed Atlantic salmon correlated well with lipid content and these other halogenated contaminants, however, lower concentrations of PBDEs (1.6 ± 0.3 ng g^?1 wet wt) showed no correlation. Possible explanations for the non‐linear behaviour of PBDE concentrations in Atlantic salmon are discussed.     

Occupational exposure to commercial decabromodiphenyl ether in workers manufacturing or handling flame-retarded rubber

Commercial decabromodiphenyl ether (DecaBDE) is commonly used as a flame retardant in different electrical and textile applications. It is also used in the production of flame-retarded rubber compound. DecaBDE is the major technical polybrominated diphenyl ether (PBDE) in use today and consists mainly of decabromodiphenyl ether (BDE-209). PBDEs, including BDE-209, are well-known environmental pollutants, ubiquitous both in aquatic and terrestrial environments. The aim of the present study was to assess the exposure to PBDEs in workers manufacturing or handling rubber which was flame retarded with DecaBDE. A referent group, abattoir workers (slaughterhouse workers), with no occupational exposure to PBDEs, was also investigated. Moreover, the methodology for analysis of PBDEs in serum was refined, with special emphasis on congeners with a high number of bromine substituents, i.e., octa- to decaBDEs. The highest BDE-209 concentration observed among the rubber workers was 280 pmol/g lipid weight (I.w.) (270 ng/g I.w.). The median concentration of BDE-209 among rubber workers was 37 pmol/g I.w. (35 ng/g I.w.). Among referents, the median was 2.5 (range 0.92-9.7) pmol/g I.w. (median 2.4 ng/g I.w.). In rubber workers the BDE-209 concentrations were up to 32% (median 4%) of the 2,2',4,4',5,5'-chlorobiphenyl (CB-153) concentrations, on a molar basis, whereas the referents had BDE-209 concentrations which were similar to that of 2,2',4,4'-bromodiphenyl ether (BDE-47), below 1.4% (median 0.3%) of the CB-153 concentration. Concentrations of all nonabromodiphenyl ethers (nonaBDEs) and several octabrmodiphenyl ethers (octaBDEs) congeners, including BDE-203, were also elevated among the rubber workers, with 2.5- to 11-fold higher median concentrations, compared to the referents. The results confirm a significant uptake of BDE-209 in the workers exposed to DecaBDE and indicate a potential for in vivo formation of lower BDEs in these persons.     

Levels of specific polychlorinated biphenyl congeners in fatty foods from five Canadian cities between 1986 and 1988.

A total of 155 fatty food composites from five major Canadian cities were analysed for 36 selected polychlorinated biphenyl (PCB) congeners. Total PCB congener levels of more than 1 ng/g (wet weight) were found in fresh water fish, canned fish, butter, marine fish and cheese, with fresh water fish (18.7 ng/g) containing 5 to 10 times more total PCBs than the other four food commodities. Milk (2%), cooking oils/salads and canned meat soup contained less than 0.1 ng/g (wet weight). The observed total PCB residue levels in fatty foods were well within the Canadian guidelines for fish, dairy products, poultry, eggs and beef. The most predominant congeners found in fish, butter, cheese, meat and poultry were the 2,2',4,4',5-, 2,3',4,4', 5-pentachloro-, 2,2',3,4,4',5'-, 2,2',4,4',5,5'-hexachloro- and 2,2',3,4,4',5,5'-heptachlorobiphenyls. The predominant congener pattern was not always evident in other dairy products (e.g. ice cream) and processed foods (e.g. canned meat soup). An attempt was made to relate the intake of PCB congeners from fatty foods with congener levels found in adipose tissue of Canadians. The estimated daily intake of some specific PCB congeners from fatty foods, in most cases accounted for more than half the total deposit of these congeners in adipose tissue of Canadians.     

Remarkable findings concerning PBDEs in the terrestrial top-predator red fox (Vulpes vulpes)

In the present study, we have analyzed muscle, liver, and adipose tissue of 33 red foxes from Belgium for their content of polybrominated diphenyl ethers (PBDEs). Median sums of seven tri- to hepta-BDEs (BDE 28, BDE 47, BDE 99, BDE 100, BDE 153, BDE 154, and BDE 183) were 2.2, 2.4, and 3.4 ng/g lipid weight in adipose tissue, liver, and muscle, respectively. These levels were lower than those found in various species of voles and mice, the main prey species of the red fox. This is probably related to the high capacity of the foxes to metabolize and eliminate lower brominated congeners. BDE 209 generally dominated the PBDE congener profiles in the red fox samples. In samples containing BDE 209, this congener contributed, on the average, approximately 70% to the total PBDE content. BDE 209 was measured in concentrations as high as 760 ng/g lipid weight in the liver, but the detection frequency was not more than 40%. In animals with the highest BDE 209 levels, this congener was detected in muscle, liver, as well as in adipose tissue. Other abundant congeners were BDE 153 and BDE 47, which prevail in other terrestrial species. The particular PBDE congener profile observed in the red fox resembles that seen in grizzly bears from Canada, but differs from those previously reported for terrestrial avian species. Our data confirms unambiguously that BDE 209 does bioaccumulate in terrestrial top predators, such as the red fox.     

Fate, partitioning, and mass loading of polybrominated diphenyl ethers (PBDEs) during the treatment processing of municipal sewage

Sewage treatment plant (STP) effluents are likely a major source of contamination for PBDEs, especially in the receiving water bodies of local aquatic environments surrounding the location of these discharges. Congeners of the pentaBDE mixture, 2,2,',4,4'-tetrabromodiphenyl ether (BDE47), 2,2,',4,4',5-pentabromodiphenyl ether (BDE99), 2,2,',4,4',6-pentabromodiphenyl ether (BDE100), 2,2,',4,4',5,5'-hexabromodiphenyl ether (BDE153), and 2,2,',4,4',5,6'-hexabromodiphenyl ether (BDE154), are of great environmental concern in North America due to their persistence, potential for bioaccumulation, and >97% use of the global production of the mixture in the region. Detailed characterization of the distribution of eight PBDE congeners (2,4,4'-tribromoDE (BDE28) and BDE47, 99, 100, 138, 153, 154, and 183) was carried out at five sites along the treatment process at an activated sludge-type secondary treatment municipal STP facility. PentaBDE mixture congeners, sigma5PBDE (sum of BDE47, 99, 100, 153, and 154) accounted for >98% of the total (sigma 8) PBDE concentration at all sites, with over 80% of the composition being BDE47 and BDE99. Presence of dissolved organic matter affected the mobility of PBDEs during the initial stages of the treatment process. About 9% of the influent mass of sigma5PBDE to the facility is estimated to be discharged into the Little River (leading to the Detroit River) with the final effluent, resulting in an estimated mass loading of approximately 0.7 kg/year. The total mass loading of sigma5PBDE to the Detroit River is expected to be much larger as effluent from this facility accounts for <10% of the total STP discharges to the river.     

Serum concentrations of polybrominated diphenyl ethers (PBDEs) and polybrominated biphenyl (PBB) in the United States population: 2003-2004

Polybrominated diphenyl ethers (PBDEs) and 2,2',4,4',5,5'-hexabromobiphenyl (BB-153) are chemicals known as brominated flame retardants. We have assessed the exposure status of the United States population to PBDEs and BB-153 and explored associations with demographic information, including participants' age, sex, and race/ethnicity. A total of 2,062 serum samples, from participants in the National Health and Nutrition Examination Survey (NHANES) 2003-2004 aged 12 years and older, were analyzed for PBDEs and BB-153; stratified and regression analyses were used to examine levels among demographic groups. The congener with the highest serum concentration was 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) [geometric mean 20.5 ng/g lipid]; followed by 2,2',4,4',5,5'-hexaBDE (BDE-153) [5.7 ng/g lipid]; 2,2',4,4',5-pentaBDE (BDE-99) [5.0 ng/g lipid; a value equal to the highest limit of detection for an individual sample]; 2,2',4,4',6-pentaBDE (BDE-100) [3.9 ng/g lipid]; BB-153 [2.3 ng/g lipid]; and 2,4,4'-triBDE (BDE-28) [1.2 ng/g lipid]. For BDE-47, we observed no significant difference in the least-squares geometric mean (LSGM) by sex, but with age we found both a linear decrease (p = 0.01) and a positive quadratic trend (p = 0.01). Its LSGM, 27.9 ng/lipid, in the 12-19 year olds decreased to 17.2 ng/g lipid in the 40-49 year group, and then curved upward to 20.4 ng/g lipid in the > or =60 years olds. Mexican Americans had the highest LSGM of BDE-47 (24.5 ng/g lipid), which was significantly higher than that of non-Hispanic whites (19.7 ng/g lipid, p = 0.01). Adults 60 years and older were twice as likely as adults 20-59 years old to have a serum BDE-47 concentration above the 95th percentile (p = 0.02).These data provide needed exposure assessment data for public health decisions.     

Polybrominated diphenyl ethers (PBDEs) in biota representing different trophic levels of the Hudson River, New York: from 1999 to 2005

It has been hypothesized that a principal route of human exposure to polybrominated diphenyl ethers (PBDEs), used as flame retardants, is through fish consumption. Between 1999 and 2005 PBDE-47, -99, -100, -153, and -154 were analyzed in 3797 biological samples of 33 species of the Hudson River, New York. Approximately 98.4% of the samples contained PBDEs between 0.5 and 37 169 ng g(-1) lipid, with a median concentration of 772 ng g(-1) lipid. Yearly median sigmaPBDE concentrations fluctuated. Samples from river miles 112 and 153 contained higher sigmaPBDEs than those from other locations of the river. The 7-year median sigmaPBDE concentrations were the highest in large carnivorous fishes and the lowest in insects. The median abundance of congener PBDE-47 decreased from 80% to 63% with decreasing levels of sigmaPBDEs in the samples, while an increase from 2% to 23% was observed for PBDE-99. The median abundance of other congeners did not change with concentrations of sigmaPBDEs. Positive-, negative-, and no-correlation between sigmaPBDE concentrations and fish weight were observed for different species and for the same species from different locations of the river. The sources of PBDE contamination, diet, metabolic activity, and sediment chemistry might affect the levels of PBDEs in a fish.     

Brominated flame retardants in polar bears (Ursus maritimus) from Alaska, the Canadian Arctic, East Greenland, and Svalbard

Polybrominated diphenyl ethers (PBDEs) were determined in adipose tissue of adult and subadult female polar bears sampled between 1999 and 2002 from sub-populations in Arctic Canada, eastern Greenland, and Svalbard, and in males and females collected from 1994 to 2002 in northwestern Alaska. Only 4 congeners (BDE47, 99, 100, and 153) were consistently identified in all samples. BDE47 was the major PBDE congener representing from 65% to 82% of the sum (sigma) PBDEs. Age was not a significant covariate for individual PBDEs or sigmaPBDE. Higher proportions of BDE 99, 100, and 153 were generally found in samples from the Canadian Arctic than from Svalbard or the Bering-Chukchi Sea area of Alaska. Geometric mean sigmaPBDE concentrations were highest for female polar bear fat samples collected from Svalbard (50 ng/g lipid weight (lw)) and East Greenland (70 ng/g lw). Significantly lower sigmaPBDE concentrations were found in fat of bears from Canada and Alaska (means ranging from 7.6 to 22 ng/g lw).     

Hair as an indicator of endogenous tissue levels of brominated flame retardants in mammals

Few data are available on brominated flame retardants (BFRs) in terrestrial mammalian wildlife. Moreover, the use of hair in nondestructive monitoring of BFRs in mammals or humans has not been investigated. In the present study, concentrations of polybrominated diphenyl ethers (PBDEs) and brominated biphenyl 153 (BB 153) were analyzed in tissues of the European hedgehog Erinaceus europaeus. Road kills and carcasses from wildlife rescue centers were used to investigate relationships between concentrations of BFRs in hair and internal tissues, BFR tissue distribution (hair, liver, kidney, muscle, and adipose tissue), and PBDE congener tissue pattern dissimilarities. Liver concentrations of PBDEs and BB 153 were in the ranges 1-1178 and 0-2.5 ng/g of liver wet weight, respectively. PBDEs were predominant in adipose tissue and liver, while accumulation of BB 153 was tissue independent. The less persistent compound BDE 99 was more dominant in hair than in internal tissues. We observed positive relationships between BFR levels in hair and internal tissues for sum PBDEs and BDE 47 (0.37 < r < 0.78). The present study demonstrated that hair is a suitable indicator of PBDE exposure in terrestrial mammals which can be used in nondestructive monitoring schemes.     

Brominated flame retardants, polychlorinated biphenyls, and organochlorine pesticides in captive giant panda (ailuropoda melanoleuca) and red panda (Ailurus fulgens) from China

Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and brominated flame retardants (BFRs) were investigated in captive giant and red panda tissues from China. The total concentrations of OCPs, PCBs, and polybrominated diphenyl ethers (PBDEs) in tissues ranged from 16.3 to 888 ng/g lipid weight (lw), 24.8 to 854 ng/g lw, and 16.4 to 2158 ng/g lw, respectively. p,p'-DDE and beta-HCH were major OCP contaminants. PCBs 99, 118, 153/132, 170, 180, and 209 were the major contributing congeners determined. Among PBDEs, congener BDE-209 was the most frequent and abundant, followed by BDE-206, BDE-208, BDE-207, BDE-203, BDE-47, and BDE-153. Decabromodiphenyl ethane (DeBDethane) was detected in 87 and 71% of the giant and red panda samples with concentrations up to 863 ng/g lw, respectively. The remarkable levels and dominance of BDE-209 and DeBDethane may relate to significant production, usage, or disposal of BFRs in China. The positive significant correlation between concentrations of PBDEs and PCBs in captive pandas may suggest that the exposure routes of PBDEs and PCBs to panda are similar. To our knowledge, this is the first report of the occurrence of DeBDethane in captive wildlife samples. Therefore, further studies are warranted to better understand DeBDethane production, transport, uptake, and toxicological effect.     

High postnatal exposures to polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) via breast milk in California: does BDE-209 transfer to breast milk?

Breast milk samples collected during 2003-2005 from 82 first-time mothers in 24 communities located throughout California contained levels of polybrominated diphenyl ethers (∑(tri-hexa (8))PBDEs; median = 53.3 ng/g lw, range = 9.60-1291) and polychlorinated biphenyls (∑(12)PCBs; median = 73.4 ng/g lw, range = 22.2-433) that are among the highest in the world. PBDE levels varied 100-fold. BDE-47 was the dominant PBDE congener, with levels exceeding the U.S.EPA Reference Dose (RfD) for neurodevelopmental toxicity (100 ng/kg/day) in most (60%) breast milk samples. In some samples, BDE-209 (2/82) and/or BDE-153 (5/82) were the dominant congeners, suggesting that BDE-209 can transfer to breast milk and/or break down in the mother and transfer to the nursing infant as the lower-brominated PBDEs associated with adverse effects. PBDE levels in California breast milk are approaching those of PCBs, and the trend PBDEs > PCBs may continue as PBDEs migrate from products to the indoor and outdoor environments.     

Asian Mussel Watch Program: contamination status of polybrominated diphenyl ethers and organochlorines in coastal waters of Asian countries

Mussel samples were used in this study to measure the levels of polybrominated diphenyl ethers (PBDEs) and organochlorines (OCs) in the coastal waters of Asian countries like Cambodia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, the Philippines, and Vietnam. PBDEs were detected in all the samples analyzed, and the concentrations ranged from 0.66 to 440 ng/g lipid wt. Apparently higher concentrations of PBDEs were found in mussels from the coastal waters of Korea, Hong Kong, China, and the Philippines, which suggests that significant sources of these chemicals exist in and around this region. With regard to the composition of PBDE congeners, BDE-47, BDE-99, and BDE-100 were the dominant congeners in most of the samples. Among the OCs analyzed, concentrations of DDTs were the highest followed by PCBs > CHLs > HCHs > HCB. Total concentrations of DDTs, PCBs, CHLs, and HCHs in mussel samples ranged from 21 to 58 000, 3.8 to 2000, 0.93 to 900, and 0.90 to 230 ng/g lipid wt., respectively. High levels of DDTs were found in mussels from Hong Kong, Vietnam, and China; PCBs were found in Japan, Hong Kong, and industrialized/urbanized locations in Korea, Indonesia, the Philippines, and India; CHLs were found in Japan and Hong Kong; HCHs were found in India and China. These countries seem to play a role as probable emission sources of corresponding contaminants in Asia and, in turn, may influence their global distribution.     

Polybrominated diphenyl ethers in the environment and in people: a meta-analysis of concentrations

Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in many types of consumer products. Perhaps as a result of their widespread use and their lipophilicity, these compounds have become ubiquitous in the environment and in people. This review summarizes PBDE concentrations measured in several environmental media and analyzes these data in terms of relative concentrations, concentration trends, and congener profiles. In human blood, milk, and tissues, total PBDE levels have increased exponentially by a factor of approximately 100 during the last 30 yr; this is a doubling time of approximately 5 yr. The current PBDE concentrations in people from Europe are approximately 2 ng/g lipid, but the concentrations in people from the United States are much higher at approximately 35 ng/g lipid. Current PBDE concentrations in marine mammals from the Canadian Arctic are very low at approximately 5 ng/g lipid, but they have increased exponentially with a doubling time of approximately 7 yr. Marine mammals from the rest of the world have current PBDE levels of approximately 1000 ng/g lipid, and these concentrations have also increased exponentially with a doubling time of approximately 5 yr. Some birds' eggs from Sweden are also highly contaminated (at approximately 2000 ng/g lipid) and show PBDE doubling times of approximately 6 yr. Herring gull eggs from the Great Lakes region now have PBDE concentrations of approximately 7000 ng/g lipid, and these levels have doubled every approximately 3 yr. Fish from Europe have approximately 10 times lower PBDE concentrations than fish from North America. From these and other data, it is clear that the environment and people from North America are very much more contaminated with PBDEs as compared to Europe and that these PBDE levels have doubled every 4-6 yr. Analyses of the relative distributions of the most abundant PBDE congeners (using category averages and principal component analysis) indicated that these patterns cannot yet be used to assign sources to these pollutants.