PCBs and other organochlorines in human tissue samples from the Welsh population: I--Adipose

The general exposure of humans to polychlorinated biphenyls (PCBs) and SigmaDDT (i.e., p,p'-DDT + p,p'DDE = p,p'-DDD) in Wales (UK) was determined through the analysis of adipose tissue samples collected from 75 individuals during post-mortem examinations in 1990-1991. Fifty PCB congeners were screened, of which 29 were identified in most of the samples. Congener IUPAC numbers 138, 153 and 180 were the most abundant compounds, accounting for an average of 55% of the SigmaPCB congeners analysed. SigmaPCB concentrations varied between 0.2 and 1.8 microg g(-1) of adipose tissue and were positively correlated with the donors age and negatively associated with the percentage of lipid in the adipose tissue. A progressive change in the congener pattern was noted with increasing subject age. Tissue from older individuals generally contained a relatively high proportion of the more persistent and higher chlorinated congeners. SigmaDDT concentrations ranged from 0.11 to 5.6 microg g(-1) adipose tissue, with p,p'-DDE contributing 96% towards the SigmaDDT concentration. SigmaDDT levels were also positively correlated with age. No significant differences in the SigmaPCB and SigmaDDT concentrations were noted between males and females, between people living in rural and urban locations or with the subjects' body weight at the time of their death.     

Organochlorine contaminants in northeast Atlantic minke whales (Balaenoptera acutorostrata)

Blubber samples of 72 minke whales (Balaenoptera acutorostrata) were obtained from the northeast Atlantic in July and August 1992, and evaluated for organochlorine contamination. The following organochlorines were determined: the industrial chemicals PCBs (polychlorinated biphenyls), and the organochlorine pesticides DDTs (dichlorodiphenyltrichloroethanes), HCHs (hexachlorocyclohexaneb), HCB (hexachlorobenzene) and CHLs (chlordanes). The concentrations of SigmaPCB (sum of concentrations of 18 PCB congeners) and SigmaDDT (sum of concentrations of p,p'-DDT, p,p'-DDE, p,p'-DDD, o,p'-DDT and o,p'-DDD) ranged from 0.6-20.8 and 0.5-14.8 microg g(-1) lipid weight, with mean concentrations at 3.8 and 2.5 microg g(-1) lipid weight, respectively. The mean concentrations of HCB, the chlordane metabolites oxychlordane, cis-chlordane and trans-nonachlor, and the HCH isomers (alpha-, beta- and gamma-HCH) were all < 1 microg g(-1) lipid weight. Significantly higher concentrations of the three major pollutants (SigmaPCB, SigmaDDT and SigmaCHL) were found in mature males as compared to mature females and juveniles of both sexes. No such relationship was found for SigmaHCH and HCB. Stomach contents of northeast Atlantic minke whales indicate considerable heterogeneity in the diet when comparing different years, seasons and geographical areas. However, without knowing more about the minke whale migration pattern, or possible geographical segregation with age and sex, the interchemical variation of organochlorines between sampling areas may not reflect true geographical differences.     

Can seal eating explain elevated levels of PCBs and organochlorine pesticides in walrus blubber from eastern Hudson Bay (Canada)?

Walrus (Odobenus rosmarus) blubber samples from Inukjuak and Akulivik (East Hudson Bay), Foxe Basin (Igloolik and Hall Beach) and Loks Land (East Baffin Island) were analysed for PCB congeners (ortho and non-ortho substituted) and other persistent organochlorines (DDT, toxaphene, chlordanes, dieldrin, mirex), as well as chlorinated dioxins/furans, to document spatial trends in contaminants in Canadian Arctic marine biota. Samples from 19 of 53 individuals had concentrations of SigmaPCBs greater than 1000 ng g(-1) (wet wt); the remaining individuals had much lower concentrations (50-600 ng g(-1)). Highest concentrations were found in samples from Inukjuak where average concentrations in blubber of females (N = 9) were 1450 +/- 954 ng g(-1) toxaphene, 2750 +/- 1780 ng g(-1) SigmaCHLOR, 2160 +/- 925 ng g(-1) SigmaDDT and 4790 +/- 2380 ng g(-1) SigmaPCB. SigmaPCB and SigmaDDT concentrations greater than 1000 ng g(-1) were unexpected based on previous studies of walrus from Greenland and Alaska. Local contamination was ruled out because levels of all organochlorines were elevated in each animal from Inukjuak, and elevated levels were also found in animals from Akulivik and Loks Land. Walrus from Inukjuak had sigma13C and sigma15N values in muscle intermediate between those of ringed seals (Phoca hispida) and those of walrus from Akulivik with low organochlorine levels. There was a weak but significant correlation between and sigma15N and (log)SigmaPCB. The Inukjuak walrus also had higher proportions of highly chlorinated PCB congeners, and higher DDE/SigmaDDT ratios than walrus from Igloolik or Akulivik. The results suggest that the walrus with elevated organochlorines are feeding at a higher trophic level than those with low levels and are probably utilizing ringed seals for a portion of their diet.     

Levels of polychlorinated biphenyls and organochlorine pesticides in serum samples of Egyptian Vulture (Neophron percnopterus) from Spain

Concentrations of 23 polychlorinated biphenyls (PCBs), p,p'-DDT and two of its metabolites, p,p'-DDE and p,p'-TDE have been measured in serum samples of up to 1 ml of Egyptian Vulture (Neophron percnopterus) gathered from five populations in Spain. SigmaPCB concentrations were found to be in the range 3.2-97 ng/ml, while those of SigmaDDTs ranged from 0.93 to 38 ng/ml. p,p'-DDT/p,p'-DDE ratios higher than one were only found in the Segovia population, which could be an indication of recent use of p,p'-DDT in the area. In all cases, PCB profiles were dominated by congeners 52, 132 + 105, 138, 153 and 180. However, some differences among the five populations studied became evident when their profiles were compared with those of technical PCB mixtures by principal components analysis. The DDT and PCB levels detected in the serums analysed were lower than those previously reported for similar avian species and those reported to have deleterious effects on survival or reproduction of birds.     

Persistent organochlorines in beluga whales (Delphinapterus leucas) from the St Lawrence River estuary--I. Concentrations and patterns of specific PCBs, chlorinated pesticides and polychlorinated dibenzo-p-dioxins and dibenzofurans

Blubber samples from beluga whales (Delphinapterus leucas) in the St Lawrence River estuary were analysed for PCB congeners (ortho- and non-ortho-substituted) and other persistent organochlorines as well as chlorinated dibenzo-dioxins/furans (PCDD/Fs). Major individual components (mean concentrations > 1 microg g(-1)) were 4,4'-DDE, -DDD and -DDT, T12 (a toxaphene-related compound), trans-nonachlor, oxychlordane, mirex, HCB, tris(p-chlorophenyl) methane and dieldrin. Concentrations of SigmaPCBs (8.3-412 microg g(-1)), SigmaDDT (3.36-389 microg g(-1)) and mirex (0.18-6.8 microg g(-1)) were particularly elevated relative to other odontocetes in Canadian waters. SigmaDDT, PCBs (as Aroclor), mirex and T12 concentrations were positively correlated with age of adult females (> 10 years) but only weakly, or not significantly, correlated with age of adult males. PCDD/Fs were present at low ng kg(-1) levels and consisted mainly of penta- and hexachlorofurans, and hepta- and octachlorodioxin. CB126 (3,3',4,4',5-PCB) was the most prominent non-ortho-substituted PCB congener in beluga blubber. Total TCDD toxic equivalents averaged 330 ng kg(-1) in females and 1400 ng kg(-1) in males and were dominated by CB126, and the mono-ortho-substituted congeners CB105 and CB118. Biomagnification factors (BMFs) for mirex and SigmaPCB from fish to beluga ranged from 11 to 16, and were similar to BMFs in Arctic animals, indicating that elevated levels in St Lawrence animals are a consequence of relatively high levels of recalcitrant organochlorines in prey of the beluga in the St Lawrence river system.     

Contamination of human milk in Middle Hesse, Germany--a cross-sectional study on the changing levels of chlorinated pesticides, PCB congeners and recent levels of nitro musks

Human milk samples from women in Middle Hesse, Germany were chemically analyzed for contamination levels of alpha-, beta- and gamma-HCH, HCB, p,p'-DDE and p,p'-DDT as well as the PCB-congeners no. 28, 31, 49, 52, 101, 118, 138, 153, 156, 170 and 180. Changes in concentrations of these compounds in human milk over an extended time period were studied by comparing samples from 1984/85, 1990/91 and 1995. In addition, concentrations of the nitro-aromatic compounds musk xylene and musk ketone were determined in the 1995 samples. The study showed statistically highly significant (p<0.001) reductions in levels of beta- and gamma-HCH, HCB, p,p'-DDE and p,p'-DDT, in human milk from 1995 compared to samples from 1984/85. A weakly significant reduction (p<0.05) of alpha-HCH was also observed. For low-chlorinated PCB congeners, on the other hand, a highly significant increase of PCB no. 28 was detected and concentrations of congeners no. 31, 49 and 52 remained unchanged. Concentrations of the high-chlorinated congeners no. 101, 138, 153 and 180 dropped (highly significant). A highly significant reduction of PCB no. 118 and 156 occurred between 1990/91 and 1995, but a highly significant increase was found for no. 170. Lower levels of hydrocarbon contamination of human milk samples from 1995 than were found in samples from 1984/85 and 1990/91 can be seen to result partially from voluntary reductions, but primarily reflect restrictive environmental legislation in the Federal Republic of Germany. Mean concentrations of musk xylene and musk ketone in samples from 1995 were 41 microg/kg and 10 microg/kg milk fat, respectively.     

Serum polychlorinated biphenyl and organochlorine insecticide concentrations in a Faroese birth cohort

A prospective birth cohort of 1022 participants was established in the Faroe Islands over a 21-month period during 1986-1987. We collected questionnaire data on potential persistent organic pollutant (POP) concentration predictors, such as duration of breastfeeding and blubber consumption. To assess the participants' exposure from in utero to 14 years of age to polychlorinated biphenyls (PCBs) and the insecticide p,p'-DDT and its primary degradate p,p'-DDE, we measured 37 PCB congeners and pesticides in 316 umbilical cord samples taken from participants at birth, in 124 serum samples collected from participants at approximately 7 years of age, and in 795 serum samples collected from participants at 14 years of age. Measurements of higher chlorination PCB congeners made on individuals' serum samples collected at 7 years and 14 years were highly correlated (typically r > 0.5, p > 0.01), although their concentrations at 7 years were generally two to three times higher than at 14 years. Similarly, umbilical cord PCB concentrations were correlated with PCB concentrations in both 7- and 14-year serum samples. Sex-specific differences in higher chlorination PCB and p,p'-DDE concentrations were found at 14 years but not at 7 years, although a sex interaction with blubber consumption and nursing duration was observed at both ages. Both duration of breastfeeding and consumption of blubber were significant predictors of serum summationPCB concentrations at 7 and 14 years. Multivariate analyses showed that breastfeeding duration was the primary contributor to serum summationPCB concentrations at 7 years, and blubber consumption was the primary contributor at 14 years. These data suggest that infant exposures from breastfeeding were sufficiently large so that continued exposures to PCBs, p,p'-DDT, and p,p'-DDE through the diet have not fully diluted their contribution to the summationPCB and p,p'-DDE body burden of the children.     

Organochlorine contaminants in narwhal (Monodon monoceros) from the Canadian Arctic

Organochlorine pesticides (DDT, chlordane, polychlorinated camphenes (PCCs), dieldrin, hexachloroheclohexanes (SigmaHCH), mirex), polychlorinated biphenyl congeners (PCBs) and chlorobenzenes (SigmaCBz) were determined in blubber and liver of narwhal (Monodon monoceros) collected during 1982-1983 from Pond Inlet on northern Baffin Island in the Canadian Arctic. PCCs were the predominate organochlorines in narwhal blubber, ranging in concentration from 2990 to 13 200 ng g(-1) (wet wt) in males and from 1910 to 8390 ng g(-1) in females. PCCs consisted of two major components, an octachlorobornane and a nonachlorobornane with gas chromatographic retention times of 1.05 and 1.22, relative to 4,4'-DDE. SigmaPCB concentrations in blubber ranged from 2250 to 7290 ng g(-1) in males and from 894 to 5710 ng g(-1) in females. Seven PCB congeners (tetra-, penta- and hexachlorobiphenyls) accounted for 45% of total PCB (SigmaPCB) in narwhal blubber. Narwhal had 1.4- to 8.6-fold higher ratios of tetra- and pentachlorobiphenyls to PCB-153 (2,2',4,4',5,5'-hexachlorobiphenyl), lower 4,4'-DDE/SigmaDDT ratios and lower proportions of trans-nonachlor to total chlordane components than reported for odontocetes living in more contaminated environments. Mean SigmaPCB concentrations in narwhal were 6- to 15-fold lower than in dolphins from the Canadian east coast and belugas from the St Lawrence River estuary, respectively, while PCC levels were from 4- to about 2-fold lower, and SigmaHCH, dieldrin and SigmaCBz differed by <2-fold. The pattern of organochlorines in narwhal tissues suggests they are exposed to proportionally more volatile compounds, and may have less capacity to metabolize some of these compounds, relative to odontocetes living nearer sources of these contaminants.     

Analysis of Gulf of Mexico bottlenose dolphins for organochlorine pesticides and PCBs

Organochlorine concentrations were determined in blubber samples from 33 Tursiops truncatus stranded on the Texas and Florida coastlines. All tissues had measurable concentrations of 4,4'-DDE (0.18-70.7 microg/g lipid weight) and SigmaPCB (4.1-149 microg/g lipid weight). Pesticide and PCB concentrations were similar to those reported in Tursiops truncatus from the Atlantic coast of the United States and the southeast coast of Africa. Organochlorine concentrations were highest in mature males, and differences in the SigmaPCB/SigmaDDT ratios between mature and immature males suggests a recent decrease in DDT uptake, related to the commercial DDT ban in the US in 1971, as well as dietary differences between younger and older animals. Analysis of a female and her calf indicate that females reduce their own organochlorine body burden through transplacental transfer. However, no reduction of some higher molecular weight PCBs was found. Transplacental transfer rates of 5.1% for SigmaDDT and 3.7% for SigmaPCB were determined based on a stranded female and her full term, unborn calf. Predictions of uptake and depuration rates of organochlorines based on gender in Tursiops truncatus agree with clearance rates from previous studies.     

Distribution of organochlorine pesticides, polychlorinated biphenyls and alpha-HCH enantiomers in pork tissues

The distribution of HCH isomers, DDT analogues and selected PCB congeners in pork organs collected from the same individuals raised in Romanian farms was investigated. Organochlorine pesticides (HCHs and DDTs) were the principal contaminants in all samples, while PCB concentrations were low, in accordance with previously reported concentrations from Romanian animal farms. The most part of the pollutant load in the body is retained in the adipose tissue, with HCHs ranging between 16 and 27.7 ng/g lipid and with higher concentrations of DDTs ranging between 65.9 and 334.5 ng/g lipid. The highest PCB levels (up to 32 ng/g lipid) were measured in lung and liver. The lipid-normalized concentrations in the brain were lower than in all other tissues due to the presence of the blood-brain barrier or due to a lower proportion of the neutral lipids such as triglycerides. The highest concentrations of DDTs were measured in muscle and fat, with p,p'-DDE being the principal contributor and with a variable contribution of p,p'-DDD and p,p'-DDT. In liver, p,p'-DDD has a higher contribution to the sum DDTs, while in all analyzed livers, the concentration of p,p'-DDT was very low. beta-HCH was the most persistent HCH isomer in all tissues, accounting for 40-97% of sum HCHs. For all animals, the highest concentrations of beta-HCH and HCHs were found in liver, while the lowest HCH concentrations were measured in brain and spinal marrow. Additionally, the distribution of alpha-HCH enantiomers in the tissues was discussed. In all samples (except 2 brain samples), (+) alpha-HCH was depleted and (-) alpha-HCH was enantioenriched. Enantiomeric ratios in brain were the highest measured values between all organs. For all studied animals, ERs increased in the order fat < muscle < liver < brain.     

Relationship between two consecutive lactations and fat level in persistent organochlorine compound concentrations in human breast milk

An attempt was made to understand how consecutive deliveries and the following lactations have an impact on the organochlorine compound levels detected in human milk. The other goal of the study was to check for a possible dependence between fat content and the levels of the studied compounds in milk samples from the same lactations. 199 milk samples were examined for the presence of p,p'-DDT, p,p'-DDE, p,p'-DDD, alpha-, beta-, gamma-HCH and sigmaPCBs. Moreover, in 87 milk samples the fat content was additionally determined. This study has indicated that, for the mother with a shorter interval between lactations, mean concentrations of the examined compounds were higher in the milk of the first lactation than that of the second. For the other donor whose second lactation began after 2 years, the mean levels of HCB, beta-HCH, p,p'-DDD, and PCBs in her milk were higher during the first lactation. At the same time, the concentrations of p,p'-DDT and p,p'-DDE after the second delivery were slightly higher. The correlation coefficients between the two data sets (fat content in milk, concentrations of the compounds studied in milk) showed no interrelationship between them.     

Persistent organic pollutants (POP) in a benthic omnivore--a comparison between lake and stream crayfish populations

We investigated the accumulation of PCB and DDT in crayfish populations in 10 streams in southern Sweden. The results were compared with an earlier study on crayfish in lakes from the same area. We found that the concentration of pollutants in crayfish did not differ between the two types of systems. Variation in body burden was higher in stream living crayfish probably because of the higher influence from pollutants deposited in the catchment area and the more dynamic transport in streams. In streams, p,p'-DDE concentrations were positively correlated to trophic status (total phosphorous) while PCB did not show any correlation with the nutrient regime. Further, mean SigmaPCB and p,p'-DDE concentrations in crayfish did not correlate in streams. We suggest that the sources of the two pollutants differ for stream living crayfish. The results indicate that crayfish in streams are affected to a higher degree to pollutants in the catchment area and the precipitation regime. In lakes, internal processes govern uptake of pollutants in crayfish.     

Pesticides and PCBs in sediments and fish from the Salton Sea, California, USA

The Salton Sea, the largest manmade lake in California, is officially designated by the State of California as an agricultural drainage reservoir. The purpose of this study was to determine organochlorine and organophosphorous pesticides, as well as polychlorinated biphenyl (PCB) concentrations in sediments and fish tissues in the Salton Sea and evaluate the relative ecological risk of these compounds. Sediment samples were taken during 2000-2001 and fish tissues (Tilapia mossambique, Cynoscion xanthulu) were collected in May 2001. All samples were analyzed for 12 chlorinated pesticides, 6 organophosphorus pesticides, and 55 polychlorinated biphenyl (PCB) congeners. SigmaDichlorodiphenyltrichloroethane (SigmaDDT) and total PCB concentrations observed in sediments ranged from 10 to 40 and 116 to 304 ng/g dry wt, respectively. DDT/DDD ratios in sediments and fish tissues of the northern Sea in 2001 indicated recent DDT exposure. Lindane, dieldrin, dichlorodiphenylethane (DDE) and total PCB concentrations detected in sediments exceeded probable effect levels established for freshwater ecosystems, and pp-DDE and total PCB concentrations were higher than effect range-median values developed for marine and estuarine sediments. In fish liver, concentrations of endrin and SigmaDDT exceeded threshold effect level established for invertebrates. SigmaDDT concentrations detected in fish tissues were higher than threshold concentrations for the protection of wildlife consumers of aquatic biota. DDE concentrations in fish muscles tissues were above the 50 ng/g concentration threshold for the protection of predatory birds. Dimethoate, diazinon, malathion, chlorpyrifos, disulfoton varied from < or = 0.15 to 9.5 ng/g dry wt in sediments and from < or = 0.1 to 80.3 ng/g wet wt in fish tissues. Disulfoton was found in relatively high concentrations (up to 80.3 ng/g) in all organs from Tilapia and Corvina. These results demonstrate continued contamination of specific organochlorine compounds in sediments and resident fish species of the Salton Sea.     

Levels of persistent organochlorine residues in eggs of greater flamingos from the Guadalquivir marshes (Doñana), Spain

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) residue levels were determined in 53 unhatched eggs from greater roseus flamingos (Phoenicopterus ruber). Eggs were collected in 1996 from the National Park of Do?ana (Guadalquivir marshes, Southwest Spain), immediately after one breeding colony abandoned the nesting site due to predator attacks. The main metabolite of p,p'-DDT, p,p'-DDE, was the OCP residue found at higher concentrations, with a geometric mean of 721 ng/g wet weight. Residues of other pesticides, including some hexachlorocyclohexane isomers, hexachlorobenzene, aldrin, heptachlor, and heptachlor-epoxide, were detected at much lower concentrations. The sum of PCBs was 528 ng/g, with PCB congeners #187 and #153 being the most prominent in eggs. The pattern observed in these compounds of industrial origin corresponded more to Aroclor 1260 than to any other commercial mixture. Levels of organochlorine residues indicate a medium degree of exposure, and they are not considered of any concern for the flamingo population. In particular, neither p,p'-DDE nor PCB levels were found to be correlated with the eggshell thickness.     

Occurrence and vapor particle partitioning of heavy organic compounds in ambient air in Brazzaville, Congo

High volume air samples for organochlorine (OC) pesticides, polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAH) were collected during August-September 1989 in Brazzaville, Congo (4.14 degrees S, 15.14 degrees E). Average concentrations (ng/m3) were SigmaDDT=2.8; Sigma HCH (hexachlorocyclohexane)=0.42; Sigmachlordane=0.027; SigmaPCB=0.55 Sigma3-6 ring PAH=42; total DDT concentrations in Brazzaville fell between those reported in Porto Novo and Delhi (India) and were 20-100 times higher than those found in US cities. The average gamma-HCH to alpha-HCH ratio (11) indicated use of lindane instead of technical HCH. The similarities between chlordane levels in Brazzaville and the open ocean indicated that little or no local use occurs. PAH levels were about equal to or lower than those reported in US cities, whereas PCB levels were three times lower. Vapor/particle distribution coefficients for several OC and PAH were in good correlation with their vapor pressures. The fraction of PAH on particles was greater than that of OC pesticides.     

Occurrence and accumulation of organochlorine contaminants in swordfish from Mediterranean Sea: a case study

Polychlorinated biphenyls including coplanar congeners and DDT compounds were measured in the liver of a teleost species: namely, Xiphias gladius. PCB concentrations (median: 1121 ng/g lipid wt) were comparable with DDT levels (median: 1236 ng/g lipid wt). PCBs revealed a profile dominated by hexa-, penta- and heptachlorinated congeners. Among DDTs, the compound in the greatest concentration was p,p'-DDE, representing 70% of the total DDT burden, followed by o,p'-DDT>p,p'-DDT>p,p'-DDD=o,p'-DDD. Mean total 2,3,7,8-TCDD equivalent of five coplanar PCBs was 8.83 pg/g lipid weight. The isomers with higher TEQs values were non-ortho congeners than mono-ortho ones.     

Polybrominated diphenyl ethers and selected organochlorine chemicals in grey seals (Halichoerus grypus) in the North Sea

Blubber samples from grey seal (Halichoerus grypus) pups were collected in 1998 through to 2000. Twenty four newly weaned pups were sampled in November 1998, 13 of which were re-sampled during their first year of life, between March and December 1999, and an additional 48 and 25 samples (new cohorts) were obtained in 1999 (November-December) and 2000 (May-September) respectively. SimgaPBDE concentrations (sum of Di-HxBDEs) ranged from 45 to 1500 ng/g lipid, with a geometric mean of 290 ng/g lipid. BDE 47 dominated the congener profile, followed by BDEs 100, 99, 153 and 154. SimgaPCB concentrations (sum of 41 congeners) ranged from 100 to 93000 ng/g lipid, with a geometric mean of 4600 ng/g lipid, with CB congeners 153, 138 and 180 making up 84% of the total PCB concentrations. The predominant OC pesticides were p,p'-DDE (geometric mean=860 ng/g lipid, range=160-3800 ng/g lipid) and p,p'-DDT (geometric mean=120 ng/g lipid, range=30-670 ng/g lipid). No significant differences were found between males and females, probably due to the young age of the animals. Significant decreases (P<0.01 for PBDEs and P<0.05 for PCBs/OCs) were observed between newly weaned seals in 1998 and 1999, but not for the majority of juveniles in 1999 and 2000. Significant differences (P<0.01) were also found between the different seasons in 1999 newly weaned and juvenile seals, reflecting changes in blubber mass.     

Organochlorine contaminants in hair of adolescents from Iassy, Romania

Human hair samples (n=42) from Iassy county (Eastern Romania) collected in 2002-2003 from adolescents were analyzed for hexachlorocyclohexane (HCH) isomers, p,p'-DDT and its metabolites, hexachlorobenzene (HCB), chlordane and metabolites and 5 polychlorinated biphenyl (PCB) congeners. Very low levels were found for HCB and oxychlordane (0.8 and 2.5 ng g(-1)) indicating a low usage of these pesticide formulations in the studied area. In case of HCHs, gamma-HCH isomer was measured at higher median concentrations (79 ng g(-1) hair) compared to the beta-HCH isomer (55 ng g(-1)), which generally is the most prevalent from HCHs. The DDTs profile consisted in p,p'-DDE and p,p'-DDT which levels correspond to 81% of sum DDTs. Very high median concentrations measured for p,p'-DDT (192 ng g(-1)) combined with lower values for p,p'-DDE/p,p'-DDT of 0.4 (from 0.20 to 2.0) in all hair samples suggest recent exposure to "fresh" DDT. When gender was considered, significantly higher concentrations for most of the investigated contaminants were found in girls hair compared to boys. Very high levels were found in the present study for HCHs and DDTs compared to samples from Greece, Western Europe and China. In case of PCBs, the levels found in Romanian samples were found to be in the same range compared to other previously published data.     

PCB, DDT, arsenic, and heavy metal (Cd, Cu, Pb, and Zn) concentrations in chameleon (Chamaeleo chamaeleon) eggs from Southwest Spain

This work presents the concentrations of twenty PCB congeners, p,p'-DDT, and its two main metabolites, p,p'-DDE, p,p'-TDE, As, Cd, Cu, Pb, and Zn found in common chameleon eggs from nine different nests located in Southwest Spain. Of the heavy metals and arsenic, Zn and Cu exhibited the highest concentrations in egg contents (ranging from 10100 to 12950 and from 567 to 706 ng g(-1) wet weight basis [w.w.], respectively) and eggshells (ranging from 5605 to 13290 ng g(-1)w.w. for Zn and from 1487 to 4361 ng g(-1)w.w. for Cu). Total PCB concentrations in egg contents ranged from 32 to 52 ng g(-1)w.w. and were higher than total dichlorodiphenylethanes concentrations (ranging from 0.67 to 1.9 ng g(-1)w.w., calculated as the sum of p,p'-DDT plus p,p'-DDE and p,p'-TDE). Comparison of the data from the present study with the data from a study conducted in 1997 revealed a large decrease in Pb concentration and a twofold increase in PCB concentrations. Taking into account all the pollutants investigated, the contamination level found in common chameleon eggs from Southwest Spain was generally lower than has been reported in the literature for eggs of different reptile species. However, it should be borne in mind that most of the data found in the literature refer to highly polluted areas.     

Congener-specific approach to human PCB concentrations by serum analysis

The objective of this study was to evaluate all congeners of polychlorinated biphenyls (PCBs) in human serum samples. Concentrations of all PCB congeners in the serum of 87 volunteers were determined by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). The participants consisted of 47 males and 40 females, including 25 men working at municipal solid waste incinerators (MSWIs). The mean concentrations of total PCBs and dioxin-like PCBs were 242.77ng/g lipid (median: 180.17ng/g lipid) and 18.57ng/g lipid (median: 15.34ng/g lipid), respectively. Penta-, hexa-, and heptachlorinated biphenyls contributed more than 80% of the total PCBs detected in human serum. Congener-specific analysis indicated that PCB153, PCB138, PCB180, PCB187, and PCB118 contributed 57.3% of the total PCBs detected in human serum samples. A statistical analysis was performed to determine whether there were significant correlations between PCB concentrations and specific variables such as age, gender, smoking habits, occupation, and body mass index (BMI). However, serum PCB concentrations correlated only with age. In addition, we found that total PCBs and dioxin-like PCBs highly correlated with PCB153 (correlation coefficient r=0.93, p<0.01) and PCB118 (correlation coefficient r=0.98, p<0.01), respectively. Thus these two congeners could be satisfactory indicators for total PCBs and dioxin-like PCBs in human serum.