Polychlorinated Dibenzo-<Emphasis Type="Italic">p</Emphasis>-Dioxins,Dibenzofurans, and Dioxin-Like Polychlorinated Biphenyls in Livers of Birds from Japan

Concentrations of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and non- and mono-ortho-chlorine-substituted polychlorinated biphenyls (dioxin-like PCBs) were measured in livers of 17 species of birds collected from Japan. Birds were grouped according to their feeding habits as granivores, piscivores, omnivores, and predators for discussions. Livers of granivores contained relatively low concentrations of PCDD/DFs (80–660 pg/g) followed in increasing order by omnivores (2,300–8,000 pg/g), piscivores (61–12,000 pg/g) and predators (480–490,000 pg/g on a fat weight basis). Especially, one species of predatory bird (mountain hawk eagle) contained elevated concentrations of PCDDs, PCDFs, and dioxin-like PCBs, and the measured concentration is one of the highest reported to date. Homolog and congener patterns of PCDDs and PCDFs varied among species; hence, the results suggested that feeding habits, specific elimination, and metabolism influence contamination pattern. Concentrations of dioxin-like PCBs were in the order of granivores (32–83 ng/g) < predators [excluding mountain hawk eagle] (32–2,500 ng/g) < piscivore (61–12,000 ng/g) < omnivores (1,800–67,000 ng/g on a fat weight basis). Mountain hawk eagle contained the highest concentration of dioxin-like PCBs (55,000 ng/g fat weight). 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) toxic equivalents (TEQs) ranged from 53–450,000 pg/g fat weight. 23478-PeCDF, 2378-TCDD/TCDF, and PCB congeners IUPAC 126 and 77 were major contributors to TEQs in birds. To our knowledge, this is the first study of PCDD/DFs and dioxin-like PCBs in livers of several species of Japanese birds. Received: 11 March 2001/Accepted: 5 August 2001     

Organochlorine Pesticides, Polychlorinated Biphenyls, and Butyltin Compounds in Blubber and Livers of Stranded California Sea Lions, Elephant Seals, and Harbor Seals from Coastal California, USA

Concentrations of polychlorinated biphenyls (PCBs), DDTs (p,p′-DDE, p,p′-DDD, p,p′-DDT), chlordanes (CHLs; cis-chlordane, cis-nonachlor, trans-nonachlor, and oxychlordane), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), tris(4-chlorophenyl)methane (TCPMe), tris(4-chlorophenyl)methanol (TCPMOH), and mono- (MBT), di-(DBT), and tri-butyltin (TBT) were determined in blubber and livers of 15 California sea lions (Zalophus californianus), 6 northern elephant seals (Mirounga augustirostris), and 10 harbor seals (Phoca vitulina) found stranded along the coasts of California, USA, during 1991–1997. Among the organochlorines analyzed, DDTs were predominant, followed in decreasing order by PCBs, CHLs, TCPMe, TCPMOH, HCHs, and HCB. The greatest concentrations of organochlorines were found in California sea lions. The highest DDT and PCB concentrations found in the blubber of California sea lions were 2,900 and 1,300 μg/g, lipid weight, respectively. Concentrations of TCPMe and TCPMOH in California sea lions were correlated significantly with DDT concentrations. Concentration ratios of various organochlorines in harbor seal livers were different from those in California sea lions and elephant seals, which suggested that the sources of exposure of harbor seals to organochlorines were different from those in the other two species. Concentrations of butyltin compounds in livers of pinniped species ranged from 2 to 99 ng/g, wet weight, which were less than those observed in cetaceans and in California sea otters. Received: 22 September 2000/Accepted: 18 December 2000     

Concentrations of Polychlorinated Dibenzo-p-Dioxins (PCDDs), Polychlorinated Dibenzofurans (PCDFs), and Dioxin-Like PCBs in Adipose Tissue of Infertile Men

Some epidemiological studies suggested the occurrence of an alteration in the male reproductive function in the past 50 years, particularly a decrease in the sperm count and quality, an increase in the malformations frequency of the reproductive apparatus (cryptorchidism and hypospadias) and of testicular cancers. Especially according the laboratory animals studies, polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) have been suspected to play a crucial and deleterious role in the alteration of human fertility. For this reason, we measured adipose tissue concentrations of PCDDs/Fs and dioxin-like PCBs in 23 fertile and 22 infertile men living in Ankara, Turkey. Adipose tissue samples were analyzed for PCDD/F and 12 dioxin-like PCB congeners using high-resolution gas chromatography/high-resolution mass spectrometry. For the fertile and infertile groups, the World Health Organization (WHO)_PCDD/F-TEQ concentrations ranged from 3.0 to 15.8 pg/g fat and from 2.8 to 17.2 pg/g fat, respectively (4.4–31.5 and 4.7–22.3 WHO-TEQs/g fat, respectively, including dioxin-like PCBs) (p > 0.05). The mean concentrations of WHO_PCDD/F-TEQ and WHO_PCB-TEQ have been calculated as 7.2 and 12.5 pg/g (on a lipid basis) for the fertile group and 7.0 and 9.4 pg/g for the infertile group, respectively. Concentrations of each of the PCDD/F and dioxin-like PCB congeners were compared in fertile and infertile groups among themselves, and no statistical significance was obtained (p > 0.05), except 2,3,7,8-tetrachlorodibenzofuran (p = 0.0029) and 1,2,3,4,6,7,8,9-octachlorodibenzofuran (p = 0.01).     

Polychlorinated Biphenyl Concentrations, Congener Profiles, and Ratios in the Fat Tissue, Eggs, and Plasma of Snapping Turtles (Chelydra s. serpentina) from the Ohio Basin of Lake Erie, USA

Concentrations and profiles of polychlorinated biphenyls (PCBs) were determined in three tissues of adult snapping turtles (Chelydra serpentina serpentina) from six locations in the Ohio Basin of Lake Erie to characterize tissue variation and geographic trends. The locations included the Ohio Areas of Concern, i.e., the Ashtabula, Black, and Maumee Rivers; the Ottawa River near Toledo; and two reference sites. Mean total PCBs were greatest in turtles from the Ottawa River followed by the Maumee, Ashtabula, and Black Rivers. All three types of samples—fat tissue (FT), eggs, and plasma—showed the same geographic trend in PCB levels. On a wet-weight basis, mean concentrations ranged from 2148 to 18,669 ng/g in FT, from 183 to 3683 ng/g in eggs, and from 18 to 201 ng/g in plasma. Across all sites, total PCB concentrations between the tissues were significantly correlated (0.001 < p < 0.005; Pearson correlation coefficient (r_P) was between 0.720 and 0.954). Two distinctly different profiles with respect to relative congener and homologue concentrations were found among the sites. One that included four of the six sites examined was characterized by hexa-chlorobiphenyl (hexa-CB) dominance followed by hepta-CBs, with PCBs no. 138 + 163, 153 + 132 + 105, and 180 being the most abundant congeners. The second profile, specific for turtles from the Ottawa River, was different from the first in that tetra-CBs were the most abundant congeners followed by hexa-CBs. Analysis of variance (ANOVA) indicated significant intertissue differences in the PCB homologue profiles, i.e., FT had a higher percentage of hepta-, octa-, and nona-CBs compared with eggs and plasma, whereas eggs showed a higher percentage of hexa-CBs. At any listed location, FT, eggs, and plasma had the same congener profile. An intertissue distribution of lipid-normalized individual congener concentrations examined by regression analyses revealed significant egg–FT, egg–plasma, and FT–plasma relations for >40 congeners (0.001 < p < 0.05). The distribution ratios determined for these congeners from the slope of the regression lines averaged 1.235 ± 0.279, 0.430 ± 0.170, and 0.387 ± 0.115, respectively. The plasma wet weight–FT lipid-normalized concentration ratios for these congeners averaged 0.012 ± 0.006. Both egg–FT and plasma wet weight–FT lipid-normalized ratios regressed against log K_ow showed significant decreases, with increasing log K_ow, indicating greater accumulation of highly chlorinated congeners in FT than in other compartments. The estimated 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents ranged from 0.007 ng/g at reference sites to 0.060 ng/g at contaminated sites and from 0.099 to 1.992 ng/g in plasma and eggs, respectively. In both plasma and eggs, coplanar-CBs were the major contributors to total toxic equivalents (TEQs). Eggs from all contaminated sites had TEQs that exceeded the lowest observed effect level TEQs proposed for bald eagle chicks, in addition to high ΣPCB levels at some of these sites, especially the Ottawa and Maumee River sites, indicate potentially increased risk to turtles and possibly other wildlife species inhabiting these ecosystems. Significant correlations of total PCBs and individual congeners between FT, eggs, and plasma indicate that blood sampling can provide a good nonlethal measure of PCB exposure and can be used to monitor environmental contamination.     

Occurrence of Pesticides, Polychlorinated Biphenyls (PCBs), and Heavy Metals in Sediments From the Dniester River, Moldova

The aim of this study was to evaluate sediments of the Dniester River, in the former Soviet republic of Moldova, for the occurrence of agricultural pesticides, polychlorinated biphenyls (PCBs), and heavy metals. In October 2001, sediment samples were collected at three locations of the Dniester River: upstream, downstream, and at the tributary of the River Byk. DDT and its metabolites were observed most frequently. Total DDT sediment concentrations ranged from 8.2 to 34.7 ng/g dry weight with the highest average concentration detected at the tributary location. Heptachlor epoxide (< 0.2–3.0 ng/g dry weight), chlordane (< 0.1–6.1 ng/g dry weight), endrin (< 0.2–2.5 ng/g dry weight), phosalone (< 0.2–1.1 ng/g dry weight), and methylparathion (< 0.2–16.8 ng/g dry weight) were also detected. Total PCB concentrations observed in sediments ranged from 68 to 763 ng/g dry wt. Total average PCB concentrations were significantly (p ≤ 0.004) higher for sediments from the downstream sampling sites compared to the upstream samples. Tetra- and trichlorobiphenyls accounted for 84 and 88% of the total residues measured in the downstream and tributary locations, respectively. In contrast, heptachlorobiphenyls were the prevailing homologues in sediments from the upstream sampling site, contributing 51% of the total PCB concentration. Predominant PCB homologues were: trichlorobiphenyl congener 28 and 37, tetrachlorobiphenyl congeners 44, 49, 52, 74, 77, and 81, and heptachlorobiphenyl congener 170. Sediment concentrations of ΣDDE (19.7 ng/g dry weight) in the tributary, heptachlor epoxide (3.0 ng/g dry weight) in the downstream, and nickel (128–170 μg/g dry weight) in all locations exceeded Probable Effect Levels (PELs) established for sediment quality in fresh water, indicating probable environmental stress and the potential for adverse effects to benthic organisms in the Dniester River.     

Levels and Profiles of Polychlorinated Dibenzo-p-Dioxins, Polychlorinated Dibenzofurans, and Polychlorinated Biphenyls in Feedstuffs and Milk From Farms in the Vicinity of Incineration Plants in Tuscany, Italy

Levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorobiphenyls (PCBs) were determined in samples of bovine and ovine milk collected in farms located in the province of Grosseto, Tuscany, in the vicinity of two incineration plants as well as in farms located in areas with presumable background levels of contamination. Samples of feedstuffs of local origin used in the investigated farms were also collected and analysed. The cumulative levels of PCDDs, PCDFs, and dioxin-like PCBs (DL-PCBs) in feedstuffs ranged from 0.25 to 0.61 pg WHO-TE/g fresh weight (fw) in the farms under impact from incinerator emissions and from 0.21 to 0.34 pg WHO-TE/g fw in the control area farms. The sums of the six non–dioxin-like indicator PCB (NDL-PCB) congeners were 0.13 to 9.3 ng/g fw and 1.2 to 1.9 ng/g fw, respectively. In milk samples, the levels detected were 0.71 to 2.9 pg WHO-TE/g fat and 0.52 to 0.59 pg WHO-TE/g fat in farms under impact from the incinerators and in the control area farms, respectively. The corresponding sums of the six indicator PCB congeners were 1.4 to 8.2 ng/g fat and 0.90 to 1.6 ng/g fat. In all samples, contamination levels were below the limits set by the European Community (EC; Commission Directive 2006/13/EC and Commission Regulation 1881/2006/EC.) No relevant differences were found between samples collected in potentially exposed areas and control areas for total toxic equivalents and cumulative analytic levels of PCDDs, PCDFs, DL-PCBs, and NDL-PCBs (p > 0.05, Mann-Whitney U test). Observed levels were in agreement with those found in other countries in areas with background levels of exposure. Congener levels and profiles of PCDDs, PCDFs, and PCBs in feedstuffs and milk samples that were compared describe congener-specific transfer behavior.     

Accumulation of Environmental Contaminants in Wood Duck (<Emphasis Type="Italic">Aix sponsa</Emphasis>) Eggs,with Emphasis on Polychlorinated Dibenzo-<Emphasis Type="Italic">p</Emphasis>-Dioxins and Polychlorinated Dibenzofurans

We measured polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), organochlorine pesticides, and mercury in wood duck (Aix sponsa) eggs collected near a North Carolina (USA) bleached kraft paper mill. Samples were taken a decade after the mill stopped using molecular chlorine. Using avian toxic equivalency factors, 2,3,7,8-tetrachlorodibenzo-p-dioxin toxicity equivalent (TEQ) concentrations were 1–30 pg/g fresh wet weight in eggs (n = 48) collected near the mill in 2002–2005 and were significantly higher than those from a reference site (<1 pg/g) 25 km away. Geometric mean wood duck egg TEQs (6 pg/g) were one-fifth those measured at this site prior to the cessation of molecular chlorine bleaching. Concentrations of mercury in wood duck eggs from nests of the Roanoke River sites ranged from 0.01 to 0.14 μg/g (geometric mean, 0.04 μg/g) and were significantly higher than those from the reference site, where concentrations did not exceed 0.04 μg/g (geometric mean, 0.02 μg/g). All concentrations were lower than those associated with adverse effects in birds. The congener profiles, lack of contamination in reference site eggs, and decline in contaminant concentrations after process changes at the mill provide strong evidence that mill discharges influenced contamination of local wood duck eggs. Collectively, the results indicate that the wood duck is an effective sentinel of the spatial and temporal extent of PCDD, PCDF, and mercury contamination.     

Polychlorinated Dibenzo-p-Dioxins, Polychlorinated Dibenzofurans, and Coplanar Polychlorinated Biphenyls in Human Milk in Osaka City, Japan

Forty-eight human milk samples were collected from primiparous mothers in Osaka City from June 1999 to January 2000 and analyzed for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like coplanar polychlorinated biphenyls (CoPCBs). Mean toxic equivalents (TEQs) in the milk were 13.86 pg I-TEQ/g fat or 16.50 pg World Health Organization (WHO)-TEQ/g fat for PCDDs and PCDFs; 9.87 pg WHO-TEQ/g fat for CoPCBs; and 23.74 pg TEQ/g fat using I-TEQ values of PCDDs and PCDFs or 26.36 pg TEQ/g fat using WHO-TEQ values of PCDDs and PCDFs for total PCDDs, PCDFs, and CoPCBs. The TEQ levels of these chemicals in human milk in Osaka City were in the range of levels in human milk surveyed in Japan, but the TEQ levels of PCDDs and PCDFs and total PCDDs, PCDFs, and CoPCBs from our study were slightly higher than average TEQ levels in human milk in Japan. When comparing our data with the latest data from the United States and some European countries, the TEQ levels of PCDDs and PCDFs in human milk from Osaka City were relatively high, whereas those of CoPCBs were ranked as being of intermediate level. Only TEQ values of CoPCBs in human milk were found to correlate with the increasing age of mothers and their estimated intake of seafood during the year before pregnancy. Concentrations of PCBs 105 and 118 contributed to TEQ values of CoPCBs associated with seafood intake, whereas those of PCBs 156, 157, 114, 189, 167, and 169 contributed to TEQ values of CoPCBs associated with increasing maternal age.     

A Survey of Dietary Intake of Polychlorinated Dibenzo-<Emphasis Type="Italic">p</Emphasis>-dioxins,Polychlorinated Dibenzofurans,and Dioxin-like Coplanar Polychlorinated Biphenyls from Food During 2000–2002 in Osaka City,Japan

Studies of the dietary intake of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like coplanar polychlorinated biphenyls (dioxin-like PCBs), collectively referred as dioxins, were conducted using the total diet study (TDS) method with food purchased in Osaka City, Japan during 2000–2002. The daily intake of dioxin-TEQ (toxic equivalent) from food per adult person was estimated respectively as 104.24 pg TEQ/person/day in 2000, 72.73 pg TEQ/person/day in 2001, and 87.28 pg TEQ/person/day in 2002, corresponding to 2.08, 1.45, and 1.74 pg TEQ/kg body weight (bw)/day for an adult weighing 50 kg. The highest contribution ratio to the total intake of dioxin-TEQ was from fish and shellfish (group 10) in each year, accounting for 77–92%. The next highest contributor was meat and eggs (groups 11-A and 11-B). An annual decrease of the intake of dioxin-TEQ was not observed clearly. Otherwise, the dietary intake of non-2,3,7,8-substituted PCDDs/PCDFs were estimated together. The intake of 1,3,6,8-TeCDD came mostly from intake of fish and shellfish (group 10), green vegetable (group 7), and the other vegetables, including mushrooms and seaweed (group 8). In addition, the intake of 1,3,6,8-TeCDF, which reportedly antagonizes 2,3,7,8-TeCDD-mediated aryl hydrocarbon hydroxylase (AHH) and ethoxyresorufin O-deethylase (EROD) induction activities, was an insufficient amount to suppress 2,3,7,8-TeCDD-mediated activities. Furthermore, we discussed different TEQ compositions of PCDDs/PCDFs to dioxin-like PCBs from food intake and in human samples and inferred that the difference was caused by low bioaccumulation properties of 3,3′,4,4′,5-PeCB (PCB 126).     

Dioxin-Like Toxicity in the Saginaw River Watershed: Polychlorinated Dibenzo-<Emphasis Type="Italic">p</Emphasis>-Dioxins,Dibenzofurans, and Biphenyls in Sediments and Floodplain Soils from the Saginaw and Shiawassee Rivers and Saginaw Bay,Michigan, USA

Sediment and floodplain soils in the Saginaw River Watershed, Michigan, USA, have been demonstrated to be contaminated with a variety of organic compounds, including polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs). Existing data indicate that, at some locations, the contamination exceeds human health risk-based regulatory levels and ecological risk-based screening levels. In this study, concentrations of PCBs including non-ortho coplanar congeners, PCDDs, and PCDFs were measured in more than 120 sediment and floodplain soil samples collected from the Shiawassee River (a tributary of the Saginaw River), the Saginaw River, and Saginaw Bay, to determine the sources and magnitude of contamination, and to elucidate the contributions from individual contaminant groups to the overall 2,3,7,8-tetrachlorodibezo-p-dioxin equivalents (TEQs). Sediment and soil extracts were also analyzed for total dioxin-like activity by means of the H4IIE-luc cell bioassay. Elevated concentrations of PCBs (>1000 ng/g, dry weight) were found in surface sediment and floodplain soil samples collected from the Shiawassee River near Chase Lake, from Middleground Island in the Saginaw River, and from subsurface sediments in Saginaw Bay. Concentrations of PCDDs and PCDFs in sediment and floodplain soils from the Saginaw River and Saginaw Bay were 2 to 3 orders of magnitude higher than concentrations in the samples from the Shiawassee River. The highest PCDD/F concentration (55,200 pg/g, dry weight in a subsurface layer) was found in sediment collected at the mouth of the Saginaw River. Concentrations of PCDFs were greater than the concentrations of PCDDs in sediment from the Saginaw River. 2,3,7,8-TCDF, 1,2,3,7,8-PeCDF, and 2,3,4,7,8-PeCDF were the major PCDF congeners found in sediments from the Saginaw River. The elevated concentrations of PCDFs, and the predominance of the less highly chlorinated PCDF congeners, in sediments from the Saginaw River were similar to previously determined characteristics of the PCDF contamination of the Tittabawassee River, another tributary of the Saginaw River. These results suggest the existence of a major source of PCDFs within the watershed. A few localized areas of high PCDD/F and PCB concentrations, with unique congener compositions, in the Saginaw River indicated the presence of other minor sources, such as wastewater treatment plants. PCDFs were the major contributors to TEQs in sediment and soils from the Saginaw River and Saginaw Bay. Approximately 30% of the samples analyzed in this study had values exceeding the screening level of 50 pg TEQ/g, dry wt, suggested for soils by the Agency for Toxic Substances and Disease Registry.     

Accumulation profiles of persistent organochlorines in waterbirds from an estuary in Korea

Persistent organochlorine pollutants (POPs), such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and organochlorine (OC) pesticides such as DDTs (dichlorodiphenyltrichloroethane), HCHs (hexachlorocyclohexane isomers), CHLs (chlordane compounds) and HCB (hexachlorobenzene), were measured in subcutaneous fat of resident and migratory birds collected from the Nakdong River estuary (NRE) in Korea. Black-tailed gull, a resident bird from the NRE, contained greater concentrations of PCDD/Fs and PCBs than the migratory birds collected in the estuary. For example, mean concentrations of PCDD/Fs in black-tailed gull (395.5 pg/g fat weight) were higher than those in migratory birds, such as greenshank (198.3 pg/g fat weight), common gull (90.9 pg/g fat weight) black-headed gull (84.2 pg/g fat weight), and common tern (47.1 pg/g fat weight). However, concentrations of DDTs and/or HCHs were great in some migratory species, such as little tern (mean DDT 6,200 ng/g fat weight) and black-necked grebe (HCHs 475 ng/g fat weight). This suggested that contamination of PCDD/Fs and PCBs in resident gulls are due to intake of locally contaminated fish near the NRE. Elevated OC pesticide levels in migratory birds indicated that these birds have been exposed to DDTs and HCHs during their migration in Southeast Asian countries where chlorinated pesticides are still used. 2,3,7,8-Tetrachloro dibenzo-p-dioxin equivalents (TEQs) were calculated using the toxic equivalency factors (TEFs) reported by World Health Organization in 1998. Four of the 2,3,7,8-substituted congeners of PCDD/Fs contributed over 90% of the TEQs. Received: 27 October 2000/Accepted: 15 April 2001     

Residues of Organochlorines in Sediments and Tilapia Collected from Inland Water Systems of Hong Kong

The levels and patterns of organochlorines including DDTs, HCHs, and PCBs were investigated in sediments and tilapia (Tilapia mossambica) collected from inland water systems [Tai Wai (S1), Fo Tan (S2), Siu Lek Yuen (S3), Tai Po (S4), and Tai Wo (S5)] in the New Territories of Hong Kong. Sediment and tilapia samples were also collected from two fish ponds for comparison. The ranges of DDTs, HCHs, and PCBs in river sediments were 2.82–8.63 ng/g (DW), 0.05–2.07 ng/g (DW), and 43–461 ng/g (DW), respectively. All these values were significantly higher (p < 0.05) than the pond sediments. Low chlorinated congeners (especially mono-, tri-, and tetrachlorobiphenyls) were enriched in sediment samples accounting for 70–80% of total PCBs.  The ranges of DDTs, HCHs, and PCBs in tilapia muscle collected from Fo Tan and Tai Wai were 28.2–40.1 ng/g (DW), 2.04–3.76 ng/g (DW) and 267–310 ng/g (DW), respectively. These values were also significantly higher (p < 0.05) than those collected from the fish ponds. Higher chlorinated PCBs (tetra-, penta-, hexa-, and heptachlorobiphenyls) were commonly found in tilapia accounting for almost 60% of the total PCBs. The effect of lipid contents in organochlorines accumulation was not significant (p < 0.05) in general. Received: 24 July 1998/Accepted: 18 November 1998     

Historical Distribution of PCDDs, PCDFs, and Coplanar PCBs in Sediment Core of Ariake Bay, Japan

Persistent organic pollutants, particularly polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), coplanar polychlorinated biphenyls (co-PCBs) and toxic equivalent quantity (pg TEQ g⁻¹) were determined in sediment samples collected from Ariake Bay, Japan. The total concentration of PCDDs/DFs in surface sediment of the Yabe River (17,000 pg g⁻¹ dry wt) was approximately 2.5-fold higher than that of the Chikugo River (7,000 pg g⁻¹ dry wt) which has the highest flow amount of about 40% inputting to the northern Bay. The congener profile suggested that dioxin sources could be close to the study area. The PCDDs concentration (12,000 pg g⁻¹ dry wt) in the sediment layer, which was corresponding to the 1960s, was reflected on the pentachlorophenol (PCP) contamination occurring at that time in Ariake Bay. The reflecting of PCP in the sediment core was significantly considered by hierarchical cluster analysis. Based on isomer-specific analysis, the tetrachlorodibenzo-p-dioxin composition showed a gradual increase from 1978–1982 toward the surface, indicating that the pollution source at that period might be more influenced by chloronitrofen than PCP. This fact was supported, based on the ratio of ΣPCDD to ΣPCDF concentration. The PCDDs/DFs-derived TEQ contributed more than 90% of the ΣTEQ (PCDDs/DFs and co-PCBs) in all the detected sediment layers. The contribution of PCBs to the total TEQ was low; however, an increasing historical trend of concentration was clearly observed.     

Polychlorinated Biphenyls and Biotransformation Enzymes in Three Species of Sea Turtles from the Baja California Peninsula of Mexico

Concentrations of polychlorinated biphenyls (PCBs) as well as the expression patterns of cytochrome P450 (CYP) enzymes and glutathione-S-transferase (GST) activities were measured in livers of loggerhead (Caretta caretta), green (Chelonia mydas), and olive ridley (Lepidocheyls olivacea) sea turtles from the Baja California peninsula of Mexico. The mean concentrations of total PCBs were 18.1, 10.5, and 15.2 ng/g wet weight (ww) respectively for the three species and PCB 153 was the dominant congener in all samples. Total PCB concentrations were dominated by penta- and hexa-chlorinated biphenyls. The mean estimated TEQs were 42.8, 22.9, and 10.4 pg/g (ww) for loggerhead, green, and olive ridley, respectively, and more than 70% was accounted for by non-ortho PCBs. Western blots revealed the presence of hepatic microsomal proteins that cross-reacted with anti-CYP2K1 and anti-CYP3A27 antibodies but not with anti-CYP1A antibody. There were no significant differences in GST activities between species. Grouping congeners based on structure–activity relationships for CYP isoenzymes suggested limited activity of CYP1A contribution to PCB biotransformation in sea turtles. These results suggest potential accumulation of PCBs that are CYP1A substrates and provide evidence for biotransformation capacity, which differs from known animal models, highlighting the need for further studies in reptiles, particularly those threatened with extinction.     

Polychlorinated naphthalenes, biphenyls, dibenzo-p-dioxins, and dibenzofurans as well as polycyclic aromatic hydrocarbons and alkylphenols in sediment from the Detroit and Rouge Rivers, Michigan, USA

Sediment from the upper Detroit and lower Rouge Rivers in southeastern Michigan, USA, were analyzed to examine the distribution of polychlorinated naphthalenes (PCNs), biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs) as well as polycyclic aromatic hydrocarbons (PAHs) and alkylphenolic compounds such as butylphenol, octylphenol, and nonylphenol (NP). Sediments from a non-point source location in Lake Michigan were also analyzed for target compounds. Concentrations of target compounds in the upper Detroit and lower Rouge Rivers varied considerably among locations, and notable spatial variation existed. Concentrations of PCNs and PCDDs/PCDFs in sediments from the upper Detroit and lower Rouge Rivers ranged from 0.08 to 187 ng/g and 69 to 1420 pg/g dry weight, respectively. Total PCBs, PAHs, and NP concentrations ranged from 8 to 25,000, 17 to 44,000, and < 10 to 60,000 ng/g dry weight, respectively. Concentrations of all target compounds except PCNs were significantly correlated with total organic carbon content of sediments. Similarly, concentrations of PCBs, PCDDs, and PCDFs were significantly correlated with each other. The distribution of organic contaminants in the upper reaches of the Detroit River and lower Rouge River suggested the presence of localized, but multiple, sources of contamination for each compound class. Conners Creek combined sewer overflow has been identified as one of the potential sources for the upper Detroit River, where the highest concentrations PCBs and PCDDs/PCDFs were found. Polycyclic aromatic hydrocarbon and NP concentrations were consistently high in sediment from the lower Rouge River. Analysis of data from selected locations suggested that PCNs contributed a greater proportion of the dioxin-like activity than PCBs and PCDDs/PCDFs contributed.     

Polychlorinated Naphthalenes and Other Organochlorine Contaminants in Swedish Human Milk, 1972–1992

The concentrations of polychlorinated naphthalenes (PCNs) were determined together with polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), 1,1-bis-(4-chlorophenyl)-2,2,2-trichloroethane (p,p′-DDT), 2,2-bis(4-chlorophenyl)-1,1-dichloroethylene (p,p′-DDE) and hexachlorobenzene (HCB) in milk, sampled in the course of 1972–92 from mothers living in Stockholm. A previously developed method for multicomponent analysis of organochlorine environmental contaminants was adapted for simultaneous analysis of PCNs. The mean recoveries of seven chlorinated naphthalene (CN) congeners added to milk prior to extraction were 76–99%. Similar recoveries were obtained for the commercial PCN product Halowax 1014. The pattern of PCNs in milk differed to a great extent from that in the commercial PCN products. The dominating congeners in breast milk were 1,2,3,5,7-pentachloronaphthalene (CN-52), 1,2,3,4,6,7- and/or 1,2,3,5,6,7-hexachloronaphthalene (CN-66/CN-67) and one unidentified tetrachloronaphthalene. There was a notable decrease in the concentrations of PCNs as was of the other organochlorine contaminants in milk from 1972 to 1992. During this time period the sum of CN congeners decreased from 3,081 to 483 pg/g milk fat and the sum of toxic equivalents of dioxin and dioxin-like compounds decreased from 100 to 39 pg/g milk fat. Received: 5 June 1997/Accepted: 20 October 1997     

Mono-ortho- and non-ortho-substituted polychlorinated biphenyls in human milk from Mohawk and control women: Effects of maternal factors and previous lactation

Fifty-four individual human milk samples from 50 mothers (20 Mohawks and 30 controls) were analyzed for four non-ortho- and eight mono-ortho-substituted polychlorinated biphenyls (PCBs). Mean total coplanar PCBs concentrations were 49 ng/g and 55 ng/g lipid for Mohawk and control women, respectively. A statistical evaluation of all analytical data reveals no significant difference of total coplanar PCB level between Mohawk and control women. The level of these contaminants is influenced by the age of the mother, number of breastfed children, and length of nursing period. Older women, primiparae, and cigarette smokers had higher levels of coplanar PCBs. In general, women had higher levels of coplanar PCBs in the first lactation and in the earlier samples of a given lactation, while levels declined both with duration of breast-feeding and with number of children nursed.The contribution of individual non-ortho- and mono-ortho-substituted PCB congeners to the total calculated toxic equivalent values (TEQ) was assessed for the breast milk samples. The levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in human milk of pooled specimens from Los Angeles, California and Binghamton, New York, widely separate cities in the United States (Schecter et al. 1989), were presented for reference purpose. The main contributions to the TEQ were PCB congeners #118 (25.8 pg/g lipid), #126 (25 pg/g lipid), #105 (10.8 pg/g lipid), and #156 (7.4 pg/g lipid). Collectively, these compounds accounted for 70% of the TEQ values. Based on the TEFs proposed by Safe (1990), the overall TEQs calculated for the monitored PCBs, were about five times those due to total PCDD/Fs.     

Bioaccumulation of Organochlorine Contaminants in Bowhead Whales (Balaena mysticetus) from Barrow, Alaska

Bowhead whale (Balaena mysticetus) blubber (n = 72) and liver (n = 23) samples were collected during seven consecutive subsistence harvests (1997–2000) at Barrow, Alaska, to investigate the bioaccumulation of organochlorine contaminants (OCs) by this long-lived mysticete. The rank order of OC group concentrations (geometric mean, wet weight) in bowhead blubber samples were toxaphene (TOX; 455 ng/g) > polychlorinated biphenyls (ΣPCBs; 410 ng/g) > dichlorodiphenyltrichloroethane-related compounds (ΣDDT; 331 ng/g) ≥ hexachlorocyclohexane isomers (ΣHCHs; 203 ng/g) ≥ chlordanes and related isomers (ΣCHLOR; 183 ng/g) > chlorobenzenes (ΣCIBz; 106 ng/g). In liver, ΣHCH (9.5 ng/g; wet weight) was the most abundant ΣOC group, followed by ΣPCBs (9.1 ng/g) ≥ TOX (8.8 ng/g) > ΣCHLOR (5.5 ng/g) > ΣCIBz (4.2 ng/g) ≥ ΣDDT (3.7 ng/g). The dominant analyte in blubber and liver was p,p′-DDE and α-HCH, respectively. Total TOX, ΣPCBs, ΣDDT, and ΣCHLOR concentrations in blubber generally increased with age of male whales (as interpreted by body length), but this relationship was not significant for adult female whales. Biomagnification factor (BMF) values (0.1–45.5) for OCs from zooplankton (Calanus sp.) to bowhead whale were consistent with findings for other mysticetes. Tissue-specific differences in OC patterns in blubber and liver may be attributed to variation of tissue composition and the relatively low capacity of this species to biotransform various OCs. Principal component analysis of contaminants levels in bowhead blubber samples suggest that proportions of OCs, such as β-HCH, fluctuate with seasonal migration of this species between the Bering, Chukchi, and Beaufort Seas. Received: 10 October 2001/Accepted: 14 December 2001     

Deposition of Organochlorine Pesticides,PCBs (Aroclor 1268), and PBDEs in Selected Plant Species from a Superfund Site at Brunswick,Georgia, USA

Deposition of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were measured in Loblolly pine needles (Pinus taeda) collected in and around a Linden Chemicals and Plastics (LCP) Superfund Site at Brunswick, Georgia, USA. For the comparison, foliage of eastern red cedar (Juniperus virginiana) was also collected to monitor contaminant levels. This study revealed that concentrations of OCPs, PCBs and PBDEs ranged from 0.75–10, 3.4–15 to 0.05–3, ng/g wet wt, respectively in both plant species. Total OCPs concentrations in pine needles decreased from 10 to 2.3 ng/g; and total PCBs decreased from 28 to 9.3 ng/g between 1997 and 2006. To our knowledge, this is the first report on PBDEs concentrations in pine needles and red cedar foliage samples from the Superfund Site at Brunswick, Georgia, USA.     

Growth-Related Changes in Heavy Metal Accumulation in Green Turtle (Chelonia mydas) from Yaeyama Islands, Okinawa, Japan

Concentrations of nine heavy metals (Fe, Mn, Zn, Cu, Pb, Ni, Cd, Co, and Hg) were determined in liver, kidney, and muscle of 50 green turtles (Chelonia mydas) collected from Yaeyama Islands, Okinawa, Japan, to elucidate growth-related changes in heavy metal accumulation during different growth stage. Considerably high Cu concentrations were found in the liver of smaller turtles. Mean hepatic concentration of Cu was 50.2 μg/g wet weight which varied widely (4.27–113 μg/g wet weight). Cadmium concentrations decreased with increasing the carapace length. The juvenile green turtles in the pelagic ocean are likely feed on zooplankton, while adult coastal inhabiting green turtles mainly feed on sea grasses and seaweeds. Concentrations of Cd in sea plants are lower than those in zooplankton. The specific accumulation of Cd found in the green turtle seems to be attributable to their feeding habit, which is a shift from carnivore to herbivore at different growth stages. Received: 13 September 1999/Accepted: 29 March 2000