Brominated flame retardants and organochlorine pollutants in aquatic and terrestrial predatory birds of Belgium: levels, patterns, tissue distribution and condition factors

Liver and muscle samples from 7 species of aquatic and terrestrial predatory birds from Flanders (Belgium) were analysed for polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs) and organochlorine pesticides (OCPs). PCBs were the predominant compounds in our samples, which showed highest concentrations in the liver of barn owl (Tyto alba) and sparrowhawk (Accipiter nisus) (up to 1000 microg/g lipid weight). PBDEs could be determined in most samples at lower concentrations than PCBs (up to 64 microg/g lipid in sparrowhawk liver). Sparrowhawks had the highest levels of hexachlorobenzene, DDTs and PBDEs. In contrast, kestrels (Falco tinnunculus) had relatively low levels of most measured organochlorines. BDE 47 was the most abundant congener in heron (Ardea cinerea) and grebe (Podiceps cristatus), while BDE 47, 99 and 153 were equally important in the terrestrial species. BDE 183 and BDE 209 were only measured in the terrestrial birds. These results indicate that terrestrial birds may be more exposed to higher brominated BDE congeners than aquatic species.     

Distribution of polychlorinated biphenyls and polybrominated diphenyl ethers in birds of prey from Switzerland

Polychlorinated biphenyls (PCBs) and the structurally related polybrominated diphenyl ethers (PBDEs) have been associated with chronic neurotoxicity involving reduced motor activity and impaired attentiveness. Such neurobehavioral effects indicate that the central nervous system may represent an important target organ for the action of these persistent contaminants in wildlife. As a consequence, the brain of different terrestrial and aquatic birds collected in Switzerland was analysed for PCBs and PBDEs. In parallel, the same contaminants were examined in the accompanying adipose tissue. After clean-up by means of glass columns containing acidified silica, deactivated alumina and anhydrous sodium sulphate, the samples were analysed by high resolution gas chromatography/tandem mass spectrometry (HRGC-MS/MS). Median PCB concentrations in the brain (sum of PCB 28, PCB 52, PCB 101, PCB 118, PCB 138, PCB 153 and PCB 180) ranged between 13 ng g(-1) wet weight (ww) in blackbirds (Turdus merula) and 428 ng g(-1) ww in sparrow hawks (Accipiter nisus). Median PBDE concentrations in the brain (sum of BDE 28, BDE 47, BDE 99, BDE 100, BDE 153, BDE 154 and BDE 183) ranged from below the decision limit in buzzards (Buteo buteo) and blackbirds, to 14 ng g(-1) ww in sparrow hawks. After correction for the respective lipid content, higher PCB or PBDE concentrations in brain compared to adipose tissue, were found in three sparrow hawks, four buzzards and in all investigated blackbirds. These results suggest that a deficit in the neuroprotective function of the blood-brain barrier may cause unexpected levels of PCBs and PBDEs in the central nervous system.     

Levels and distribution of polybrominated diphenyl ethers (PBDEs) in marine fishes from Chinese coastal waters

Concentrations of polybrominated diphenyl ethers (PBDEs) in yellow croakers (Pseudosciaena crocea) and silver pomfrets (Pampus argenteus) collected from nine coastal cities along the eastern China coastline were investigated. PBDE congeners with mono- to hexa-brominated substitutions were detected in the samples, indicating their ubiquitous distribution in the marine environment of China. The total PBDE concentration averaged 3.04 ng g⁻¹ lipid wt, a level that was relatively lower than in other regions of the world, especially North America where Penta-BDE was extensively used. Geographically, the highest concentration of PBDEs was found in Xiamen, and the PBDE levels in yellow croakers were significantly higher than those in pomfrets in most of the selected cities, a pattern which may be related to the different feeding habits of the two species. The congener profiles of PBDEs were found to be different from the commonly detected pattern in fishes from other regions of the world (i.e., BDE47 > BDE99, BDE100 > BDE153, BDE154). BDE47 and BDE154 were the predominant congeners in both species, accounting for more than 60% of the total PBDE concentrations. The reasons for the relatively high proportion of BDE154 may be due to the debromination of higher brominated congeners such as BDE183 and BDE209 by these two species.     

Brominated flame retardants and organochlorine pollutants in eggs of little owls (Athene noctua) from Belgium

Residues of brominated diphenylethers (PBDEs), organochlorinated pesticides (OCPs) and polychlorinated biphenyls (PCBs) were measured in 40 eggs of little owls (Athene noctua), a terrestrial top predator from Belgium. The major organohalogens detected were PCBs (median 2,600 ng/g lipid, range 790-23 000 ng/g lipid). PCB 153,138/163, 170, 180 and 187 were the predominant congeners and constituted 71% of total sum PCBs. PBDEs were measurable in all samples, but their concentrations were much lower than for PCBs, with a range from 29-572 ng/g lipid (median 108 ng/g lipid). The most prevalent PBDE congeners in little owl egg samples were BDE 47, 99 and 153. This profile differs from the profile in marine bird species, for which BDE 47 was the dominant congener, indicating that terrestrial birds may be more exposed to higher brominated BDE congeners than marine birds. The fully brominated BDE 209 could be detected in one egg sample (17 ng/g lipid), suggesting that higher brominated BDEs may accumulate in terrestrial food chains. Brominated biphenyl (BB) 153 was determined in all egg samples, with levels ranging from 0.6 to 5.6 ng/g lipid (median 1.3 ng/g lipid). Additionally, hexabromocyclododecane (HBCD) could be identified and quantified in only two eggs at levels of 20 and 50 ng/g lipid. OCPs were present at low concentrations, suggesting a rather low contamination of the sampled environment with OCPs (median concentrations of sum DDTs: 826 ng/g lipid, sum chlordanes: 1,016 ng/g lipid, sum HCHs: 273 ng/g lipid). Hexachlorobenzene (HCB) and octachlorostyrene (OCS) were also found at low median levels of 134 and 3.4 ng/g lipid, respectively. Concentrations of most analytes were significantly higher in eggs collected from deserted nests in comparison to addled (unhatched) eggs, while eggshell thickness did not differ between deserted and addled eggs. No significant correlations were found between eggshell thickness and the analysed organohalogens.     

Polybrominated diphenyl ethers (PBDEs) in sediment and bivalves from Korean coastal waters

Concentrations of polybrominated diphenyl ethers (PBDEs) were determined in sediment and bivalves collected from 25 coastal locations in Korea. Twenty major PBDE congeners were found in all sediment and bivalve samples. SigmaPBDE20 concentrations ranged from 0.45 to 494 ng/g, dry weight (average 27.8 ng/g dry weight) in sediments, and from 0.38 to 9.19 ng/g, wet weight (average 2.94 ng/g wet weight) in bivalves. The highest concentrations were found at locations near industrial complexes and large harbors, suggesting that human activities contribute to PBDEs contamination in Korean coastal environment. PBDE concentrations measured in our study, excluding BDE congener 209 (deca-BDE), in sediment and bivalves were lower than those reported from other countries; whereas BDE 209 concentrations were comparable to or higher than those reported from other countries. The predominant PBDE congener in sediments and bivalves was deca-BDE, which accounted for >90% and >60% of the total PBDE concentrations in sediment and bivalves, respectively. This is consistent with high consumption of deca-BDE for the flame-retardant market in Korea. Significant correlations existed among BDEs 28, 47, 99, 100, 153 and 154 in sediments and bivalves; however, BDEs 183 and 209 showed little correlation compared with less highly brominated congeners.     

Environmental factors in debromination activity of polybrominated diphenyl ethers by hepatic microsomes of freshwater fish

Although the debromination of polybrominated diphenyl ethers (PBDEs) in fish species has been studied, environmental factors, such as chemical contamination and habitat temperature, have not been well understood. This study compared debromination of BDE209 by hepatic microsomes of wild and cultured fish. PBDE concentrations in muscle tissue were lower in cultured fish than in wild fish. Debromination activity was high in wild common carp, followed by cultured common carp, moderate in cultured ayu sweetfish, and low in two cultured fish (rainbow trout and cherry salmon) and wild Japanese sea bass. Although common carps have been known as the species which have higher debromination ability, there were differences between wild and cultured common carps. First, wild common carp debrominated much more BDE209 than cultured common carp. Second was debromination of BDE209 lasted 96 h in wild carp but only 24 h in cultured carp. Wild carp were collected from warm wastewater effluent with consistently high concentrations of micropollutants. Cultured carp were collected from colder clean waters. Therefore, environmental factors in debromination include contamination or ambient temperature. To investigate the effects of habitat environment on debromination of PBDEs, we collected wild carp in summer and winter at two different locations with similar PBDE contamination levels. Carp collected from the natural river in winter had the highest BDE99 debromination activity. Although the results indicated seasonal difference of debromination of BDE209, we could not confirm whether habitat temperature or physiological cycle of carp affected to debromination ability. Thus, further investigation such as in vivo experiment is required.

     

Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in breast milk from the Pacific Northwest

Breast milk samples from 40 first-time mothers from the Pacific Northwest of the US and Canada were analyzed for polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). Total PBDEs (summation operator PBDEs), calculated by summing values for the 12 PBDEs congeners analyzed, ranged from 6 to 321 ppb (lipid weight) (mean=96 ppb; median=50 ppb). In approximately 40% of the women (15/40), summation operator PBDEs>100 ppb lw in their milk, and four samples had levels >250 ppb lw. PBDE 47 was the dominant congener in most samples, whereas PBDE 153 was predominant in a few (3/40). summation operator PCBs were calculated by summing values for the 82 PCB congeners analyzed, and ranged from 49 to 415 ppb (lipid weight) (mean=147 ppb; median=126 ppb). approximately 30% of the mothers (13/40) have summation operator PBDEs> summation operator PCBs in their milk samples, and approximately 65% (25/40) have BDE 47>PCB 153 in breast milk samples, with BDE 47 averaging 3-fold greater levels than PCB 153. Clearly, the lower brominated PBDEs are surpassing PCBs as a major environmental concern in North America, and are likely affecting significant portions of the populations in these regions. PBDEs have become a major persistent organic pollutant. However, there are no positive correlations between levels of summation operator PBDEs and summation operator PCBs, or between levels of PBDE 47 and PCB 153, suggesting there may be some differences in exposure pathways for PBDEs and PCBs in humans.     

Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in human liver and adipose tissue samples from Belgium

Levels of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured in paired human adipose tissue and liver samples (n=25) from Belgium. Average concentrations and standard deviation of sum PBDEs (congeners 28, 47, 99, 100, 153, 154 and 183) were 5.3+/-3.0 (range 1.4-13.2) and 3.6+/-2.1 (range 1.0-10.0)ngg(-1) lipid weight (lw) in adipose tissue and liver, respectively. These concentrations were similar to reported PBDE data from Belgium and were at the lower end of the concentration range reported elsewhere in the world. In both tissues under study, BDE 153 and BDE 47 were the most abundant PBDE congeners, contributing approximately 35% and 25% to the total PBDE content. Average concentrations and range of PCBs (sum of 23 congeners) were 490 (range 70-1130) and 380 (range 90-1140)ngg(-1)lw in adipose tissue and liver, respectively. No correlation between age and concentrations of PBDEs could be found (r=0.04), while PCB concentrations correlated significantly with age (r=0.62, p<0.01, for the sum PCBs; r=0.64, p<0.01 for PCB 153 alone). Factors, such as exposure pathways (food, dust and air), rates of bioaccumulation, metabolism and elimination, influence the concentrations of PBDEs differently than those of PCBs in humans.     

Levels and distribution of polybrominated diphenyl ethers in various tissues of birds of prey

In the present study, concentrations and tissue distribution of polybrominated diphenyl ethers (PBDEs; IUPAC # 28, 47, 99, 100, 153, 154, 183, and 209) were examined in brain, adipose tissue, liver, muscle, and serum of birds of prey. Median SigmaPBDE levels (BDE 28-183) in the tissues of sparrowhawks ranged from 360 to 1900 ng/g lipid weight (lw), which was in general one order of magnitude higher than in the tissues of common buzzards (26-130 ng/g lw). There were no differences in PBDE congener patterns between the various tissues within individuals of a certain species. Inter-species differences in PBDE patterns and in particular the percentage of BDE 99, 100 and 153 were, however, pronounced between sparrowhawk and common buzzard. BDE 209 was detected in nearly all serum and in some liver samples, but not in any other tissues. This observation suggests that exposure to BDE 209 is low or that this congener is poorly accumulated. Passive (lipid content related) diffusion could not completely describe the PBDE tissue distribution, e.g. the lowest PBDE-load was measured in brain, a fairly lipid rich tissue.     

Organohalogen chemicals in human blood from the United Kingdom

Blood serum from 154 volunteers at 13 UK locations in 2003 were analysed for a range of PCBs, organochlorine pesticides and PBDEs. HCB, p,p'-DDE and p,p'-DDT and beta-HCH were the dominant organochlorine pesticides in most samples. BDEs 47, 99, 100, 153, 154 and 183 were the most regularly detected PBDEs. This study is the first report of BDE209 in UK human blood (found in 11 samples, range < 15-240 ng/g lipid). Concentration and age correlated for the less easily metabolised PCBs, p,p'-DDT and p,p'-DDE, HCB and HCHs. With increasing age females tended to have lower concentrations of the more chlorinated PCBs than males. Similar PBDE concentrations, and distributions, to those reported in the general population in Sweden in 2002 were found, despite differences in historical PBDE production and usage. There is increasing regulation to control persistent and bioaccumulative chemicals, and establishing human exposure will help to identify substances which should be urgently phased out.     

Polybrominated diphenyl ethers (PBDEs) in farmed and wild salmon marketed in the Northeastern United States

Recently, we reported on the analysis of polychlorinated biphenyls (PCBs) and chlorinated pesticides in farmed Atlantic salmon (Salmo salar) from Maine, eastern Canada, and Norway, and wild Alaskan Chinook salmon (Oncorhynchus tshawytscha). In this paper, we extend the analysis to polybrominated diphenyl ethers (PBDEs) in these samples. Total PBDE concentrations in the farmed salmon (0.4-1.4ng/g, wet weight, ww) were not significantly different from those in the wild Alaskan Chinook samples (0.4-1.2ng/g, ww), nor were significant differences found among regions. However, significant intra-regional variations in concentrations of total PBDEs and tetra-BDE 47 were observed in the salmon from the Canadian farms (p<0.01). Congener profiles were dominated by BDE-47, followed by the penta-BDEs 99 and 100. PBDE concentrations in the Canadian samples were lower than those reported two years earlier. Removal of skin resulted in no overall reduction in PBDE concentrations in our farmed salmon, and in some cases, PBDE concentrations were higher in skin-off samples. PBDEs were correlated with lipids only in the skinned samples, suggesting that there is greater accumulation and retention of PBDEs in muscle lipids than in skin-associated fat. In skin-on samples, modest correlations were observed between concentrations of PBDEs and PCBs (R(2)=0.47) and mono-ortho PCBs (R(2)=0.50), whereas PBDEs were not correlated with non-ortho PCBs.     

Organochlorine pesticides, polychlorinated biphenyls and polybrominated diphenyl ethers in Singapore's coastal marine sediments

Persistent organic pollutants (POPs) are ubiquitous pollutants in the marine environment, particular in coastal areas affected by industry and shipping traffic. POPs are known for their recalcitrance and toxicity in the environment, and there is increasing concern over their global distribution and impact upon wildlife. Marine surface sediment samples taken within 6 km of the coastline of Singapore were analyzed to determine prevailing concentrations of organochlorine pesticides (OCPs), polychlorinated biphenyl (PCBs) and polybrominated diphenyl ethers (PBDEs). Total PCB concentrations varied widely from 1.4 to 329.6 ng/g (average 73.9 ng/g), where high concentrations were detected at sample locations closest to industrial areas with intensive shipping traffic. Total DDT concentrations ranged from 2.2 to 11.9 ng/g (average 6.7 ng/g) and were lower than the concentration range of 3.3-46.2 ng/g measured for total HCH (average 18.1 ng/g). Ratios of DDT/(DDE+DDD) in sediments do not indicate recent inputs of DDT into Singapore's marine environment, but high concentrations of alpha-HCH and gamma-HCH show evidence for the usage of HCHs in Southeast Asia. Peak concentrations of cis- and trans-Chlordane were 10 ng/g. Among the PBDE congeners BDE 47, 99, and 100 only BDE 47 could be detected at a range of 3.4-13.8 ng/g (average 6.2 ng/g). The levels of OCPs, PCBs and PBDEs were compared to available data for other countries in Asia, and indicated relatively moderate levels of contamination. Peak concentrations of PCBs, HCH isomers, Chlordane, Heptachlor, Heptachlor epoxide and Dieldrin have the potential to induce ecotoxicological impacts based on levels specified in the sediment quality standards of the USEPA and Canadian Council of Ministers of the Environment.     

Polybrominated diphenyl ethers and HBCD in bird eggs of South Africa

In this paper, the first data on brominated flame retardants (BFRs), in particular polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) in eggs of bird species from South Africa are described (N=43). Concentrations of PBDEs were detected in all the studied species and in all the geographic areas. Highest concentrations of PBDEs were measured in bird eggs from the Vaal River, which is situated downstream of the most industrialized area in South Africa. Sum-PBDE concentrations were highest in eggs of one African sacred ibis (396 ng g(-1) lipid weight (lw)), possibly due to foraging on dumping sites. Lowest mean level of sum-PBDEs (2.3 ng g(-1) lw) was measured in cattle egrets (N=11) from Barberspan Sanctuary, a Ramsar site. The PBDE congener pattern showed large differences, reflecting different trophic levels, migratory behavior, distance to the source, and, exposure to different PBDE mixtures, among others. HBCD was detected only in four species, and highest levels were measured in one egg of African sacred ibis (71 ng g(-1) lw). In most species, levels of PBDEs were one to several orders of magnitude lower than levels of DDTs and PCBs. PBDEs correlated strongly with DDTs, PCBs and some other organochlorines (OCs), indicating the same source. The widespread occurrence of PBDEs in the South African avian species showed a strong need for further investigations of PBDEs in the Southern African environment.     

Contamination and potential sources of polybrominated diphenyl ethers (PBDEs) in water and sediment from the artificial Lake Shihwa, Korea

Concentrations of polybrominated diphenyl ethers (PBDEs) were determined in water and sediment collected from the artificial Lake Shihwa and surrounding creeks. Total concentrations of 23 PBDE congeners in water and sediment ranged from 0.16 to 11.0 ng L⁻¹ and from 1.3 to 18 700 ng g⁻¹ dry weight, respectively. The concentrations of BDE 209 in water and sediment were 1-2 orders of magnitude higher than the total concentrations of other PBDE congeners. The concentrations of total PBDEs and BDE 209 in sediments were the highest compared to previously reported worldwide levels. The highest concentrations of PBDEs in water and sediments were found in creeks near industrial complexes. The PBDE concentrations gradually decreased with increasing distance from the creeks to the inshore and then offshore regions of the lake. BDE 209 was a major congener, accounting for 80% of the total PBDEs in water and sediment, consistent with a high consumption of deca-BDE for the brominated flame retardant market in Korea. Non-parametric multidimensional scaling ordination showed that surrounding creeks are major pathways of PBDE contamination associated with deca-BDE technical mixtures used in industrial complexes around Lake Shihwa. A significant correlation between total organic carbon and total PBDE concentration was found in sediments, and the correlation coefficients for individual PBDE congeners relatively increased from lower to higher brominated congeners.     

Atmospheric deposition of polybrominated diphenyl ethers (PBDEs) in coastal areas in Korea

Atmospheric bulk samples were collected monthly, for one year, from urban, suburban, and rural sites located in the coastal areas of Korea, for the assessment of depositional fluxes and seasonal variations in atmospheric concentrations of PBDEs. Twenty individual PBDE congeners were found in atmospheric samples, and their depositional fluxes varied from 10.1 to 89.0 microg/m2/year. The highest depositional fluxes were found in two urbanized areas, with a strong urban-rural gradient. The relationship between PBDE and particulate depositional fluxes showed significant correlation for all locations, which suggested the association of PBDEs to particulate phase. Deca-BDE (BDE 209) was the predominant congener (>93%) in all deposition samples, which is consistent with a high consumption of deca-BDE for the flame-retardant market in Korea. Seasonal variability was observed in PBDE concentrations for the two urban sites, whereas no seasonal trend was found for either the suburban or the rural location.     

Congener-specific accumulation and environmental risk assessment of polybrominated diphenyl ethers in diverse Korean sewage sludge types

Industrial, domestic wastewater, and livestock sludge samples were collected from 23 wastewater treatment plants in Korea and analyzed for polybrominated diphenyl ethers (PBDEs). The concentrations of Σ₁₉PBDE ranged from 4.01 to 10,400 ng/g dry weight. The average Σ₁₉PBDE concentrations in industrial, domestic wastewater, and livestock sludge were 1,560?±?3,610, 402?±?148, and 27.6?±?50.4 ng/g dry weight, respectively. The composition of PBDEs differed according to the type of sludge. Among the PBDE congeners, BDE 209 was dominant in all sludge samples. After BDE 209, relatively high levels were found for BDE 28 and 47 from industrial sludge, BDE 47 and 99 from domestic wastewater sludge, and BDE 206, 207, and 208 from livestock sludge. Using hierarchical cluster analysis, sludges were divided into three groups according to PBDE congener composition. A risk assessment of PBDEs in sludge used for soil amendment was carried out. Preliminary results indicated that the potential risk of soil exposed to PBDEs in sludge was relatively low.     

Evidence of immunomodulation in nestling American kestrels (Falco sparverius) exposed to environmentally relevant PBDEs

We investigated whether exposure to environmentally relevant polybrominated diphenyl ethers (PBDEs) causes immunomodulation in captive nestling American kestrels (Falco sparverius). Eggs within each clutch, divided by laying sequence, were injected with safflower oil or penta-BDE congeners-47, -99, -100, and -153 dissolved in safflower oil (18.7 microg sigmaPBDEs/egg) approximating Great Lakes birds. For 29 days, nestlings consumed the same PBDE mixture (15.6+/-0.3 ng/g body weight per day), reaching sigmaPBDE body burden concentrations that were 120x higher in the treatment birds (86.1+/-29.1 ng/g ww) than controls (0.73+/-0.5 ng/g ww). PBDE-exposed birds had a greater PHA response (T-cell-mediated immunity), which was negatively associated with increasing BDE-47 concentrations, but a reduced antibody-mediated response that was positively associated with increasing BDE-183 concentrations. There were also structural changes in the spleen (fewer germinal centers), bursa (reduced apoptosis) and thymus (increased macrophages), and negative associations between the spleen somatic index and sigmaPBDEs, and the bursa somatic index and BDE-47. Immunomodulation from PBDE exposure may be exacerbated in wild birds experiencing greater environmental stresses.     

Polybrominated diphenyl ethers in surface sediments of the Yangtze River Delta: Levels, distribution and potential hydrodynamic influence

A total of 32 surface sediments collected from the Yangtze River Estuary, Hangzhou Bay and the Qiantang River were analyzed for polybrominated diphenyl ethers (PBDEs). The concentrations of summation operatorPBDEs (sum of 12 PBDE congeners without BDE 209) and BDE 209 varied from n.d. to 0.55 and from 0.16 to 94.6 ng/g, respectively. The spatial variability of summation operatorPBDEs concentrations indicated that waste discharge from the urban areas might been the main source of PBDEs in the Yangtze River Delta. BDE 209 was the predominant congener (approximately 90-100%) detected among the 13 congeners, consistent with the fact that technical deca-BDE mixtures are presently the dominant technical PBDE mixtures used in China. Compared to published data acquired from other locales, PBDE congeners with less than four bromines were more abundant in the present study area. The hydrodynamic conditions may likely be a significant factor in dictating the observed levels and congener distribution patterns of PBDEs.     

Brominated flame retardants in the hair and serum samples from an e-waste recycling area in southeastern China: the possibility of using hair for biomonitoring

Hair samples and paired serum samples were collected from e-waste and urban areas in Wenling of Zhejiang Province, China. The PBDE and DBDPE concentrations in hair and serum samples from e-waste workers were significantly higher than those of non-occupational residents and urban residents. BDE209 was the dominating BFRs in hair and serum samples from the e-waste area, while DBDPE was the major BFRs from the urban area. Statistically significant correlations were observed between hair level and serum level for some substances (BDE209, DBDPE, BDE99, BDE47, BDE28, and BDE17), although the PBDE congener profiles in hair were different from those in the serum. A statistically significant positive correlation between the PBDE concentrations and the working age, as well as gender difference, was observed in e-waste workers. Different sources of PBDEs and DBDPE in three groups were identified by principal component analysis and spearman correlation coefficient. Hair is suggested to be a useful matrix for biomonitoring the PBDE exposure in humans.     

Geographical distribution of polybrominated diphenyl ethers (PBDEs) and organochlorines in small cetaceans from Asian waters

Polybrominated diphenyl ethers (PBDEs) are one of the flame retardants widely used in plastics, textiles, electronic appliances, and electrical household appliances. In this study, PBDEs and organochlorine compounds (OCs) were determined in the archived samples from the Environmental Specimen Bank for Global Monitoring (es-BANK) at Ehime University. The blubber of cetaceans found stranded along the coasts of Japan, Hong Kong, the Philippines and India during the period from 1990 to 2001 were employed for chemical analysis to understand the present status of contamination and the specific accumulation of PBDEs. PBDEs were detected in all the cetacean samples analyzed, and concentrations were one or two orders of magnitude lower than for PCBs and DDTs. Concentrations of PBDEs ranged from a low value of 6.0 ng/g lipid wt. in spinner dolphin (Stenella longirostris) from India to a high value of 6000 ng/g lipid wt. in Indo-Pacific humpback dolphin (Sousa chinensis) from Hong Kong. No difference in PBDE levels between coastal and offshore species from Japan was observed, implying the existence of pollution sources in this region other than Japan. Highest concentrations of PBDEs were found in animals from Hong Kong, followed by Japan, and much lower levels from the Philippines and India, suggesting that developing nations may also have pollution sources of PBDEs. Geographical distribution of PBDEs in Asian waters was different from PCBs but similar to DDTs.