Concentrations Of Polychlorinated Dibenzofurans Research Articles

Serum levels of PCDDs, PCDFs and PCBs in non-occupationally exposed population groups living near two incineration plants in Tuscany, Italy

A pilot study was carried out in Tuscany, Italy, to provide preliminary information on the concentrations of polychlorinated dibenzodioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorobiphenyls (DL-PCBs), and selected non-dioxin-like PCBs (NDL-PCBs) in groups of subjects living in the vicinity of two incineration plants. Seventy-four volunteers were enrolled from areas identified as under a potential impact from incinerator emissions and from not exposed areas. No significant differences were observed between subjects living in the two types of areas. Total concentrations of PCDDs, PCDFs, and DL-PCBs resulted to be in the range 23–30 pg WHO–TEQ g −1, lipid base, for subjects in the 27–54 year age groups, while concentrations increased to 40–44 pgTEQ g −1 for the two 55–67 year age groups. The levels of PCDDs and PCDFs were in good agreement with those observed for unexposed population groups in Italy, while the contribution to total TEQ from DL-PCBs was appreciably higher than those currently observed in the general population in Italy and other countries. As to NDL-PCBs, serum levels of the six “indicator” congeners were in the range 240–300 ng g −1, lipid base, for subjects in the 27–54 year age groups. A raise in NDL-PCB body burden (430–470 ng g −1, lipid base) was observed for the two 55+ year age groups, in agreement with the expected age-dependent increase. The findings from this study do not show an incremental exposure to PCDDs and PCDFs in the samples from subjects living around the two incineration plants, whereas PCB congener profiles in all samples suggest a possible impact on the area of interest of industrial activities from near industrial settlements.

Concentrations of polybrominated diphenyl ethers, organochlorine compounds and nitro musks in mother’s milk from Germany (Bavaria)

The aim of this study was to determine a new spectrum of substances that will be selected for future breast milk monitoring in Bavaria, Germany. Up to now, the analysis of breast milk in Bavaria was limited to selected organochlorine pesticides (OCP) and polychlorinated biphenyls (PCB). Information on background levels of toxicologically interesting substances, such as dioxins and dioxin-like polychlorinated biphenyls (dl-PCB) or on flame retardants, such as polybrominated diphenyl ethers (PBDE) are very limited or not available for Bavaria. We present here levels on OCP, some nitro musks, indicator PCB, polychlorinated dibenzo- p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF) and dl-PCB concentrations in breast milk collected at 12 weeks post-partum of 43 primiparous mothers living in Bavaria. The average concentrations of PCDD, PCDF and dl-PCB were 4.98, 4.93 and 9.92 pg WHO-TEQ g −1 lipid, respectively. The mean contribution of PCDD, PCDF, non-ortho and mono-ortho PCB to the total WHO-TEQ is consistently about 25% each. Furthermore the concentration on PBDE in breast milk at two sampling points, 12 weeks and 16 weeks after delivery, were determined. Overall, 19 PBDE congeners were analysed, however the level of 12 PBDE congeners were below the limit of detection. BDE-153 and BDE-47 were the predominant congeners accounting for about 66% of the total PBDE. The means of the total concentrations of PBDE (five congeners) at the first and second sampling point were 1.90 and 2.03 ng g −1 lipid, respectively. Based on our results the overall concentrations of the analysed substances in milk samples from Bavaria are consistent with the levels of breast milk samples of other European countries reflecting the low background body burden of these compounds.

Congener‐specific characterization and sources of polychlorinated dibenzo‐p‐dioxins, dibenzofurans and dioxin‐like polychlorinated biphenyls in marine sediments from industrialized bays of Korea

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DLPCBs) were determined in 122 coastal sediments from heavily industrialized areas in Korea. Toxic equivalent (TEQ) concentrations of PCDD and PCDF (PCDD/F) and DLPCB ranged from 0.44 to 38.5 pg/g dry weight and from 0.01 to 38.4 pg/ g dry weight, respectively. Overall PCDD/F and DLPCB concentrations were elevated in estuarine and inner bay locations close to industrial complexes, indicating that these contaminants derived from local discharges. Concentrations of PCDD/F measured in the present study were comparable to those in industrialized areas of other countries. Nonparametric multidimensional scaling ordination and congener-specific characterization showed that combustion processes occurring in industrial complexes, including the steel industry, are the major source of PCDD/Fs in Korean coastal waters. There were no significant correlations among PCDD/ Fs, DLPCBs, and total organic carbon; however, there was moderate correlation between PCDD/Fs and DLPCBs in some coastal bays, suggesting that these chemicals have similar sources and movements in these locations.

Nondestructive Scat Sampling in Assessment of Mink (Mustela vison) Exposed to Polychlorinated Dibenzofurans (PCDFs)

The mink (Mustela vison) is often utilized as a sentinel species for ecological assessments at sites where contaminants of concern include dioxins and dioxin-like compounds. Utilizing mink scat as a nondestructive tool to determine internal exposure to dioxin-like compounds may allow for rapid, accurate estimates of exposure without the need to capture mink or their prey. To determine the relationships between concentrations of polychlorinated dibenzofurans (PCDFs) in tissues (liver and adipose) and those in scat, mink were fed PCDFs in scat during a controlled laboratory study for 180 days. Mink were fed a control diet, diets with three doses of 2,3,4,7,8-pentachlorodibenzofuran (2,3,4,7,8-PeCDF) or 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF), and a diet with an environmentally relevant mixture of the two congeners. Concentrations of PCDFs in liver and adipose were measured after 0, 90, and 180 days of exposure. Concentrations of the two PCDF congeners in mink scat were determined after 2, 23, 45, 90, and 180 days of exposure. Concentrations of both PCDF congeners in scat were significantly correlated with those in liver and adipose tissue (r(2) = 0.94-0.97, p < 0.01). This indicates that measurements of concentrations of both PCDFs in scat can be used to predict concentrations of PCDFs in liver and adipose. Assimilation and elimination characteristics of 2,3,4,7,8-PeCDF or 2,3,7,8,-TCDF and a mixture of the two congeners by mink could be predicted from concentrations of these congeners in scat. Overall, concentrations of PCDFs in mink scat can be used as a rapid and inexpensive nondestructive method to predict concentrations of PCDFs in mink when certain assumptions are met.

Dioxin-Like Toxicity in the Saginaw River Watershed: Polychlorinated Dibenzo-p-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.

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 Sigma PCDD to Sigma PCDF concentration. The PCDDs/DFs-derived TEQ contributed more than 90% of the SigmaTEQ (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.

Dioxin concentration in the blood of patients collected during medical check-up for Yusho in 2004-2005.

We measured the concentrations of polychlorinated dizenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and non-ortho coplanar polychlorinated biphenyls (non-ortho PCBs) in blood collected from 242 Yusho patients and 74 Yusho-suspected persons in 2004 and 237 Yusho patients and 114 Yusho-suspected persons in 2005. The sums of toxic equivalents (TEQ) concentrations of PCDDs, PCDFs, and non-ortho PCBs in the blood of Yusho patients in 2004 and 2005 were 126.1 and 124.2 pg TEQ/g lipid, respectively, and the concentrations were 3.4 and 3.3 times higher than those of normal controls that had been previously reported, respectively. Those of the Yusho-suspected persons were about 0.8 and 1.0 times higher than those of normal controls, respectively. Although the TEQ concentrations of PCDDs and non-ortho PCBs among Yusho patients, Yusho-suspected persons, and normal controls were nearly the same, the PCDFs levels of Yusho patients were about 9.8 and 9.5 times higher than those of normal controls in 2004 and 2005, respectively. The concentration of 2,3,4,7,8-pentachlorodibenzofuran (2,3,4,7,8-PeCDF), which was the highest among PCDFs congeners for Yusho patients, was about 10. 6 and 10.2 times higher than that of the normal controls in 2004 and 2005, respectively. In the case of Yusho-suspected persons, the concentrations were 0.9 and 1.4 times higher than those of normal controls, respectively. However, some of the Yusho-suspected persons showed a high concentration of 2,3,4,7,8-PeCDF that was approximately 15 times greater than concentrations in normal controls. Of 74 Yusho-suspected persons measured in 2004, 7 persons were officially registered as Yusho patients based on the "New Diagnostic Criteria" that officially became the diagnostic criteria for Yusho exposure on September 29, 2004, which included a concentration of 2,3,4,7,8-PeCDF in the blood, and in 2005, 14 persons of 114 Yusho-suspected persons were officially registered as Yusho patients.

Evaluation of Organochlorine Compounds (PCDDs, PCDFs, PCBs and DDTs) in Two Raptor Species Inhabiting a Mediterranean Island in Spain (8 pp)

-: DOI: http://dx.doi.org/10.1065/espr2006.01.015 Species that are at high levels of the food web have often been used as bioindicators to evaluate the presence of persistent contaminants in ecosystems. Most of these species are long-lived, so pollutant burdens may be integrated in some complex way over time. This makes them particularly sensitive to deleterious effects of Persistent Organic Pollutants (POPs). Birds have been suggested as useful organisms for monitoring pollutant levels. Traditionally such studies have been carried out with raptors such as osprey (Pandion haliaetus), peregrine falcon (Falco peregrinus), bald eagle (Haliaetus leucocephalus), etc. In this paper we present the results of a monitoring study conducted on two raptor species, osprey (Pandion haliaetus) and red kite (Milvus milvus), inhabiting a Mediterranean island (Menorca, Spain). These two species have different feeding habits; ospreys prey on fish and red kites feed on terrestrial species. This study constitutes a good opportunity to investigate if differences in feeding habits (aquatic vs. terrestrial) influences the contaminants pattern in two species inhabiting the same area. The study was conducted in a non-destructive way, using only failed eggs, to avoid the damage of the population stability. Eggs were collected during the period 1994-2000. The contaminants examined were dichlorodiphenyltrichloroethanes (DDTs, including DDT and its main metabolite, DDE), polychlorinated biphenyls (PCBs), including ortho PCBs (PCBs with at least one Chlorine atom in the ortho position): #28, 52, 95, 101, 123+149, 118, 114, 153, 132+105, 138, 167, 156, 157, 180, 170, 189, 194; and non ortho PCBs (PCBs with no Chlorine atom in the ortho position): #77, 126, 169 and all the polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) with Chlorine atoms at the 2,3,7 and 8 position (2,3,7,8-substituted PCDDs and PCDFs). The analysis of organochlorine compounds was performed using a sample treatment based on a Solid Phase Matrix Dispersion procedure. Ortho PCBs and DDTs were determined by HRGC-µECD; non ortho PCBs and PCDD/Fs were determined by HRGC-HRMS. The sum of the ortho PCB congeners analysed ranged from 0.94 to 15.03 µg/g wet weight (ww) for ospreys and from 1.0 to 11.2 µg/g ww for red kites. In both species, PCB congeners #153, #138 and #180 accounted about 75% to total ortho PCB concentrations. Regarding non ortho PCBs, for ospreys, concentrations ranged from 0.16 to 1.39 ng/g wet weight (ww) and for red kites from 0.12 to 0.51 ng/g ww, being congener #126 the most abundant. Concerning DDTs, concentration for ospreys ranged from 0.07 to 1.03 µg/g ww; and for red kites ranged from 0.90 to 2.10 µg/g ww, representing DDE more than 95% of the total DDTs, which proves a past use of DDT in the study area. Differences in contaminant levels between species are probably associated to feeding habits. The fish-eating species presents the highest PCB levels, whereas the terrestrial species exhibits the highest DDT levels. PCDD/Fs in ospreys were in the range 2.6-14.2 pg/g ww, while in red kites the range was slightly wider (22.2-43.2 pg/g ww), being PCDDs the major contributors in black kites. Ospreys had PCDDs similar to PCDF concentrations. PCDD/F profiles were mostly influenced by OCDD in both species. Non ortho PCBs were the major contributors to calculated Toxic Equivalent Quantity (TEQs) in both species. In both species studied, ortho-PCBs could represent a problem of concern since 57% of the eggs exhibited levels higher than 4 µg/g ww, reported as the level that could cause reduced hatchability, embryo mortality, and deformities in birds. Results found in this study suggest that a more detailed study to clear up possible deleterious effects of PCBs on the bird populations studied here should be done.

Contaminant Exposure of Barn Swallows Nesting on Bayou D'Inde, Calcasieu Estuary, Louisiana, USA

Current and historical point source discharges, storm water runoff, and accidental spills have contaminated the water, sediment, and biota within the Calcasieu Estuary in southwestern Louisiana. In 2003, barn swallow (Hirundo rustica) eggs and nestlings were collected beneath two bridges that cross Bayou d'Inde, the most contaminated waterway within the Calcasieu Estuary. Samples were also collected from a bridge over Bayou Teche, a reference site in south central Louisiana. Polychlorinated biphenyl (PCB) concentrations in barn swallow eggs and nestlings were significantly higher at the downstream site on Bayou d'Inde (2.8 micro g/g PCBs in eggs and 1.5 micro g/g PCBs in nestlings) than at the other two sites (< 0.2 micro g/g PCBs in eggs and nestlings at both sites). Ethoxyresorufin-O-dealkylase activity in nestling livers was significantly higher at the downstream site on Bayou d'Inde (50 pmol/min/mg) compared to the other two locations (24 pmol/min/mg, each), probably because of exposure to PCBs. Polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran concentrations in eggs and polycyclic aromatic hydrocarbons in nestlings were at background concentrations at all sites. Trace element concentrations in barn swallow eggs and nestling livers were at background levels and did not differ among the three sites. A biomarker of DNA damage did not differ among sites.

Body Burdens of Polychlorinated Dibenzo- p -dioxins, Dibenzofurans, and Biphenyls and Their Relations to Estrogen Metabolism in Pregnant Women

Polychlorinated dibenzo-p-dioxins (PCDDs, dioxins), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) are environmental endocrine disruptors that have half-lives of 7–10 years in the human body and have toxicities that probably include carcinogenesis. A high ratio of 4-hydroxyl estradiol (4-OH-E2) to 2-hydroxyl estradiol (2-OH-E2) has been suggested as a potential biomarker for estrogen-dependent neoplasms. In this cohort study of maternal–fetal pairs, we examined the relationship of PCDD/PCDF and PCB exposure to levels of estrogen metabolites in the sera of 50 pregnant women 25–34 years of age from central Taiwan. Maternal blood was collected during the third trimester, and the placenta was collected at delivery. We measured 17 dioxin congeners, 12 dioxin-like PCBs, and 6 indicator PCBs in placenta using gas chromatography coupled with high-resolution mass spectrometry. Estrogen metabolites in maternal serum were analyzed by liquid chromatography tandem mass spectrometry. The ratio of 4-OH-E2:2-OH-E2 decreased with increasing exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (β = −0.124, p = 0.004 by the general linear regression model, R = 0.4). Meanwhile, serum levels of 4-OH-E2 increased with increasing concentrations of high-chlorinated PCDFs (i.e., 1,2,3,4,6,7,8-hepta-CDF: β = 0.454, p = 0.03, R = 0.30). Altered estrogen catabolism might be associated with body burdens of PCDDs/PCDFs. Our study suggests that exposure to PCDDs/PCDFs significantly affects estrogen metabolism. Therefore, PCDD/PCDF exposure must be considered when using the OH-E2 ratio as a breast cancer marker.

Atmospheric Deposition of Polychlorinated Dibenzo-p-dioxins (PCDDs) and Polychlorinated Dibenzofurans (PCDFs) in Kanazawa, Japan

The deposition processes of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in Kanazawa, Japan were studied by examination of the concentrations of PCDDs and PCDFs (PCDD/DFs) and their tetra- to octa-chlorinated homologues in the rain. The weighted mean deposition flux was 360 pg/m2/day [7.7 pg-toxicity equivalency quantity (TEQ)/m2/day]. Deposition fluxes obtained in this study were lower than the average value of Japan, suggesting that Kanazawa is a less polluted area. The seasons with the highest and next highest deposition fluxes were winter and spring, respectively, possibly due to the presence of an inversion layer in winter and spring that reduced the atmospheric dilution of pollutants. In addition, the ratio of PCDFs to total deposition flux in winter was larger than the ratios in the other seasons, possibly due to the burning of fossil fuels for residential heating. Deposition flux of each tetra- to octa-chlorinated homologue of PCDD/DFs was negatively correlated with surface temperature. Other meteorological parameters were positively correlated with almost all tetra- to octa-chlorinated homologues, except for heptachloro dibenzo-p-dioxins (HpCDDs) and octachloro dibenzo-p-dioxin (OCDD), possibly as a result of the photochemical reaction of pentachlorophenol (PCP), which produced mainly OCDD and traces of HpCDDs. In ambient air, the two most dominant homologues were tetrachloro dibenzo-p-dioxins (TeCDDs) and OCDD, while, in soil, the two most dominant homologues were OCDD and TeCDDs. The washout ratios increased with the increase in chlorine substitution. Thus, the difference in washout ratios between homologues might be one of the reasons for the difference of the homologue profile between the air and soil.

Follow-up survey of dioxin concentrations in the blood of Yusho patients in 2002-2003.

We measured the concentrations of polychlorinated dizenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and non-ortho-coplanar polychlorinated biphenyls (Co-PCBs) in blood collected from 279 Yusho patients and 92 Yusho-suspected persons living in Japan in 2002, 269 Yusho patients and 74 Yusho-suspected persons living in Japan in 2003 and 128 normal controls living in Fukuoka Prefecture, and compared with the concentrations of these compounds among the groups. The total TEQ concentrations of PCDDs, PCDFs, and Co-PCBs in the blood of Yusho patients were 3.6 times and 3.3 times higher than those in the normal controls in 2002 and 2003, respectively. In the case of Yusho-suspected persons, the concentrations were 1.1 times and 1.0 times higher in 2002 and 2003, respectively. Among the TEQ concentrations of PCDDs, PCDFs, and Co-PCBs, the concentrations of PCDFs in the blood of Yusho patients were 10.3 times and 9.4 times higher than those of the normal controls in 2002 and 2003, respectively, whereas the concentrations of PCDDs and Co-PCBs in blood were identical in Yusho patients, Yusho-suspected persons and normal controls. Yusho patients indicated the highest concentrations ratio of PCDFs to the total TEQ concentrations. Moreover, of the PCDFs congeners for Yusho patients, the concentrations of 2,3,4,7,8-PeCDF were about 11.0 times and 10.1 times higher in 2002 and 2003 than those in normal controls. These results indicated that Yusho patients have a much higher concentration of 2,3,4,7,8-PeCDF in their blood than do unaffected persons even though over 34 years have passed since the outbreak of Yusho.

Improvement in dioxin analysis of human blood and their concentrations in blood of Yusho patients

Over 35 years have passed since the Yusho incident. We have determined the concentrations of polychlorinated dibenzo- p -dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and non-ortho-coplanar polychlorinated biphenyls (Co-PCBs) in blood samples collected from Yusho patients to establish new criteria for Yusho. Considering the fact that the concentrations of PCDDs, PCDFs and Co-PCBs in the blood samples of about 300 Yusho patients living in Japan were scheduled for measurement in 2002, it was desirable to develop more effective methods to speed up the pretreatment procedure for blood samples. In this study, we improved a method that allows many blood samples to be treated in a short period with high reproducibility in comparison with the previously described method. Using our method, we measured the concentrations of PCDDs, PCDFs and Co-PCBs in blood collected from 279 Yusho patients in 2002 and 269 Yusho patients in 2003, and compared the results with those of 52 normal controls. The extraction procedure of PCDDs, PCDFs and Co-PCBs from the blood samples was simplified. Concentrations of the PCDDs, PCDFs and Co-PCBs were measured using high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS) equipped with a solvent-cut large volume injection system. The lipid content and the concentration of each isomer of PCDDs, PCDFs and Co-PCBs in blood determined using the improved method were almost equal to those obtained by dioxin analysis organizations that used the conventional method to analyze the same blood samples. The improved method demonstrated high reproducibility based on experiments conducted using the same serum samples. These findings indicate that the improved method is essentially equivalent to the conventional method. From the concentrations of PCDDs, PCDFs and Co-PCBs in blood samples of Yusho patients measured by the improved method, it became clear that even now Yusho patients still have a much higher concentration of PCDFs in their blood than do unaffected people more than 35 years after the Yusho incident.

Blood chemistry, alpha-fetoprotein and hepatitis B surface antigen in Yusho

Summary Background and Objective: An incident of accidental human exposure to polychlorinated biphenyls (PCBs) occurred in the western part of Japan in 1968. The disease is known as Yusho, because its cause was the ingestion of rice bran oil that was contaminated with PCBs. The various symptoms such as acneform skin eruptions were observed in the early stage in Yusho patients. An important fact is that polychlorinated dibenzofurans (PCDFs) were detected in the contaminated rice oil. PCDFs have a much higher toxicity than do PCBs. Analysis of blood concentration of PCDFs was performed throughout Japan in 2002. There have been no reports on the relationship between blood concentration of PCDFs and blood chemistry, alpha-fetoprotein or hepatitis B surface antigen (HBsAg) in Yusho. This is the first study to report on the relationship between blood concentration of PCDFs and blood chemistry, alpha-fetoprotein or HBsAg in Yusho. Methods: We analyzed blood chemistry by measuring the following 20 items—total protein, serum albumin, alanine and aspartate aminotransferase, lactate dehydrogenase, alkaline phosphatase, leucine aminopeptidase, gamma-glutamyl transferase (GGT), total bilirubin, conjugated bilirubin, cholinesterase, total cholesterol, high-density lipoprotein (HDL) cholesterol, triglyceride, glucose, amylase, creatine kinase, urea nitrogen, creatinine and uric acid. Alpha-fetoprotein and HBsAg were also measured. We studied the relationship between blood concentrations of total PCDFs and the items of the blood chemistry analysis, alpha-fetoprotein and HBsAg. Results: Of the 20 items of blood chemistry, alpha-fetoprotein and HBsAg, we found three items (GGT, HDL cholesterol and creatinine) were significantly related to the total PCDF level using three-way analysis of variance (ANOVA). Conclusion: A significant relationship between three items of the blood chemistry analysis (GGTP, HDL cholesterol and creatinine) and total PCDF levels in the blood was observed in 2002. The blood concentrations of total PCBs and PCDFs have now decreased; however, the PCDFs in patients with Yusho still affect blood chemistry.

Dermatological manifestations in Yusho: correlation between skin symptoms and blood levels of dioxins, such as polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs)

Summary Background and objective: Yusho occurred in western Japan in 1968 and was caused by ingestion of rice bran oil that was contaminated with polychlorinated biphenyls (PCBs) and dioxins such as polychlorinated dibenzofurans (PCDFs). At that time, the skin symptoms presented by patients with Yusho were at their most prominent and worst severity. Analysis of blood to determine the concentration of dioxins started in 2001 in Fukuoka prefecture, and in 2002 the examination was performed throughout Japan. There have been no reports on the relationship between blood concentration of dioxins and skin symptoms in Yusho. This is the first report to examine the relationship between blood concentration of dioxins and skin symptoms in Yusho, using statistical analyses. Methods: Using the global skin severity grade, we analyzed the change in skin symptoms, which were examined at the annual medical check-up of patients with Yusho. We also investigated the relationship between the items of the annual dermatological examination and blood concentrations of total PCDFs and total PCBs. Results: The severity of skin symptoms improved significantly in the first 20 years; nowadays, however, further improvement can hardly be observed. Using three-way analysis of variance (ANOVA), we found that of the 21 items of the dermatological examination, nine were significantly related to total PCDFs, and five were related to total PCBs. Only one item was significantly related both to total PCDFs and total PCBs. Conclusion: More than 36 years have passed since the Yusho incident, and about 60% of the patients currently present with no skin symptoms. In contrast, in about 40% of the patients, characteristic skin symptoms of Yusho, such as pigmentation of skin, black comedones and acneform eruptions, could still be observed. Our analysis of the relationship between skin symptoms and blood concentrations of total PCDFs and total PCBs proves that not only PCBs but also PCDFs have an important role in the skin symptoms of Yusho.

Harbor seals (Phoca vitulina) in British Columbia, Canada, and Washington State, USA, reveal a combination of local and global polychlorinated biphenyl, dioxin, and furan signals

The harbor seal (Phoca vitulina) can serve as a useful indicator of food web contamination by persistent organic pollutants (POPs) because of its high trophic level, wide distribution in temperate coastal waters of the Northern Hemisphere, and relative ease of capture. In 1996 through 1997, we live-captured 60 harbor seal pups from three regions, spanning remote (Queen Charlotte Strait, BC, Canada), moderately industrialized (Strait of Georgia, BC, Canada), and heavily industrialized (Puget Sound, WA, USA) marine basins straddling the Canada-United States border. Biopsy samples of blubber were taken and analyzed for congener-specific polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) by using high-resolution gas chromatography-high-resolution mass spectrometry. Harbor seals in Puget Sound were heavily contaminated with PCBs, whereas seals from the Strait of Georgia had relatively high concentrations of PCDDs and PCDFs. Pattern evaluation and principal components analysis suggested that proximity to sources influenced the mixture to which seals were exposed, with those inhabiting more remote areas being exposed to lighter PCB congeners (those with lower Henry's law constant and K(ow)) that disperse more readily through atmospheric and other processes. Total toxic equivalents to 2,3,7,8-tetrachlorodibenzo-p-dioxin for the PCBs, PCDDs, and PCDFs suggest that Puget Sound seals are at greatest risk for adverse health effects, and that PCBs represent the class of dioxinlike contaminants of greatest concern at all sites.

Concentrations of polychlorinated dibenzo-p-dioxins, dibenzofurans, non-ortho polychlorinated biphenyls, and mono-ortho polychlorinated biphenyls in Japanese flounder, with reference to the relationship between body length and concentration

The concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), non-ortho polychlorinated biphenyls (non-ortho PCBs), and mono-ortho polychlorinated biphenyls (mono-ortho PCBs) in Japanese flounder (Paralichthys olivaceus, body length 10.4-36.6 cm) collected from Sendai Bay, Japan, were determined using high-resolution gas chromatography-mass spectrometry. The relationship between the concentrations of these compounds (dioxins) and the body length of the Japanese flounder was examined. The total PCDD and total PCDF concentrations did not correlate with body length (both r(2) < 0.1, both p > 0.05), whereas the total non-ortho PCB and total mono-ortho PCB (coplanar polychlorinated biphenyls, Co-PCBs) concentrations were significantly correlated (r(2)= 0.8, p < 0.05 and r(2)= 0.63, p < 0.05, respectively). The bioaccumulation properties of PCDD/Fs in Japanese flounder differed from those of Co-PCBs. Toxicity equivalency quotient (TEQ) values derived from the Co-PCBs made up 46.3%-63.7% of the total TEQ value for all the dioxins. Although the concentrations of non-ortho PCBs were lower than those of mono-ortho PCBs, the TEQ value for non-ortho PCBs was higher than that for mono-ortho PCBs. The TEQ value for non-ortho PCBs increased more with increasing body length than did the values for PCDDs, PCDFs, and mono-ortho PCBs. These results show that from the standpoint of risk management, non-ortho Co-PCBs are the most important of the dioxins in Japanese flounder.

Persistent organochlorines in the serum of the non-occupationally exposed New Zealand population

Concentrations of polychlorinated dibenzo- p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and organochlorine pesticides were measured in the serum of a sample of the New Zealand population aged 15 years and older. This was the first study to obtain representative measures of PCDDs, PCDFs and PCBs in the adult population of an entire country. Serum samples were obtained in 1996–1997. Potentially occupationally exposed individuals were excluded. Serum samples were pooled according to stratification criteria for area of residence, ethnicity, age, and sex. Of the 80 possible strata, sufficient serum for chemical analysis was available for 60, to which 1,834 individual samples contributed. For the PCDDs and PCDFs, most 2,3,7,8-chlorinated congeners were measured in all strata, with a mean toxic equivalents concentration across all strata of 12.8 ng TEQ kg −1 lipid. Seven PCB congeners were frequently measured, including the coplanar congeners #126 and #169, quantified in all strata. Of the pesticides and their metabolites, only β-HCH, dieldrin and pp ′-DDE were consistently detected across strata. There was a general trend of increasing concentration with age. There were no consistent differences between the sexes, or between people of Maori (the indigenous people of New Zealand) and non-Maori ethnicity. Concentrations of PCDDs and PCDFs tended to increase in a North–South direction, possibly reflecting greater levels of industrialization and population concentration, and concentrations of the pesticide products were highest in the South, possibly reflecting historical use patterns. Results were consistent with a recent study of concentrations of these compounds in the milk of first-time mothers.

Sources of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs), and their bioaccumulation through the marine food web in Sendai Bay, Japan.

The concentrations of PCDD/F and Co-PCB congeners in seawater, sediment, Pacific oyster, Japanese anchovy, marbled sole, and Japanese flounder samples from Sendai Bay, Japan, were analyzed. The compositions of total PCDD/F and total Co-PCB concentrations in sediment and Pacific oyster reflected that in seawater--the compositions of total PCDD, PCDF, and Co-PCB concentrations were approximately 60, 10, and 30%, respectively. The compositions in Japanese anchovy, marbled sole, and Japanese flounder were different from those in seawater and sediment-the ratio of total Co-PCB concentration to total PCDD/F plus Co-PCB concentrations in Japanese anchovy, marbled sole, and Japanese flounder was above 90%. Tetrachlorinated PCDDs (T4CDDs), such as 1,3,6,8- and 1,3,7,9-T4CDD, were the predominant congeners in seawater and sediment; the total T4CDD concentrations in seawater and sediment were approximately 46 and 48% of the total PCDD concentration. Furthermore, shipments of the herbicide 1,3,5-trichloro-2-(4-nitrophenoxy)benzene to Miyagi Prefecture, the so-called granary of Japan, were the highest in Japan over the last 12 years. The major sources of PCDD/Fs and Co-PCBs in Sendai Bay, which is in Miyagi Prefecture, are impurities in chlorinated herbicides. The order of concentration of PCDD/Fs was Pacific oyster > Japanese anchovy = marbled sole > Japanese flounder; the concentration in Japanese flounder, which is a higher-trophic-level consumer in the marine food web, was lower than that in shellfish (Pacific oyster) and Japanese anchovy, which are lower-trophic-level consumers. The order of concentration of Co-PCBs was Pacific oyster < Japanese anchovy = marbled sole < Japanese flounder; the concentrations in the higher-trophic-level consumers were higher than the concentrations in the lower-trophic-level consumers. Different PCDD/F congeners tended to bioaccumulate in different organisms. On the other hand, all species of Co-PCB congener tended to bioaccumulate in all organisms.

Fish intake, plasma ω-3 polyunsaturated fatty acids, and polychlorinated dibenzo-p-dioxins/polychlorinated dibenzo-furans and co-planar polychlorinated biphenyls in the blood of the Japanese population

To evaluate background exposure levels and determinants of the individual variations in the exposure to dioxins in Japan. A cross-sectional study was performed on 131 men and 122 women (aged 20-76 years), who resided in five prefectures of Japan and had no occupational exposure to dioxins. Seven polychlorinated dibenzo-p-dioxins (PCDDs), ten polychlorinated dibenzo-furans (PCDFs) and 12 polychlorinated biphenyls (PCBs), which are assigned a toxicity equivalent factor, were determined in fasting blood. Biochemical analysis of plasma and a questionnaire survey on life-style, including dietary habit, were also performed. Factors associated with the levels of dioxin-related compounds in blood were evaluated by multiple linear regression. The median of total toxicity equivalents (TEQs) in men and women was 17 and 16 pg TEQ/g lipid, respectively, with no gender difference. After adjustment for age and other covariates, plasma concentrations of eicosapentaenoic acid, a biomarker of fish intake, were found to be positively associated with blood levels of total dioxin, PCDDs, PCDFs and PCBs, all of which were expressed on a TEQ basis (P<0.01). The frequency of intake of coastal fish, such as horse mackerel, mackerel and sardine, was also associated with TEQ-based concentrations of PCDFs (P=0.03) and PCBs (P=0.08). The intake of raw fish was positively related to total dioxins (P=0.06) and PCBs (P=0.03). The level of intake of marine fish, especially raw fish and coastal varieties, may be associated with increased blood levels of dioxin-related compounds among the population. Despite high fish consumption in Japan, the body burden of dioxins in the population was not found to be higher than that in western countries.