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Background and Objectives: Dioxin, classified as a human carcinogen by International Cancer Research Institute, shows inconsistent results on type 2 diabetes mellitus (T2DM) and cancer in epidemiological studies. International Cancer Research Institute classifies dioxin as a human carcinogen, but epidemiological studies of its effects on type 2 diabetes mellitus (T2DM) and cancer show inconsistent results. Therefore, we conducted a Korean population study to ascertain if the blood concentration of dioxin-like polychlorinated biphenyls (DL-PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/DFs) is associated with T2DM and thyroid cancer.Methods: Within a nested case-control study, we identified 15 people diagnosed with thyroid cancer, 30 people diagnosed with T2DM, and 55 for control. Due to the 4ml human blood requirement for PCDD/DF and DL-PCB concentrations tests, a total of 500 samples were used in 100 pooling samples. The continuous variable of a pooled sample was calculated as an average value taking into account the blood weight of each sample. The odds ratios (ORs) and 95% confidence interval (95% CI) for determining the association between total dioxins and risk of T2DM and thyroid cancer were estimated using the multivariable logistic regression.Results: The study population included 100 participants from the KCPS-II (median [IQR] baseline age, 54.06 [21.04] years; 48 women). The toxic equivalents of PCDD/DFs showed a significant positive association with T2DM and thyroid cancer, after adjustments for potential confounders (T2DM ORs = 1.23; 95% CI = 1.05-1.43; Thyroid cancer ORs = 1.34; 95% CI = 1.12-1.61). These results showed a stronger association in women than in men.Conclusion: In this study, both T2DM and thyroid cancer appear to be associated with the levels of PCDD/DFs serum. The association between T2DM and levels of PCDD/DFs serum is found in women and not in men. Our findings suggest that further biochemical in vivo research and epidemiologic studies are needed to clarify the nature of the association between dioxins concentrations and diseases.

This study investigates the use of selected ion flow tube mass spectrometry with an automated headspace pretreatment system for the continuous surveillance of water quality at wastewater treatment plants (WWTPs) and rivers. The reaction rates of the target compounds introduced using the headspace method were similar to those of the mass scan library, with a margin of error of &lt, 10%. Novel quantitative formulae were derived for the water samples of the target compounds, and the linearity of the calibration curves for both the purified and effluent matrix (0.1&ndash, 2.0 mg/L) showed a coefficient of determination of 0.98&ndash, 0.99 for most compounds. The detection limit for 74% of the target substances was 0.02&ndash, 0.10 mg/L, and the average recoveries were 111.6% and 104.7% for the low- and high-concentration spiked samples, respectively, which are comparable to those of the headspace gas chromatography-mass spectrometry system. However, the variability in individual concentrations was still large, due to the unstable control of sample injection flow and pressure. Herein, 79% of the 28 compounds met one-tenth of the proposed method detection limit criteria for emergency operations in WWTP. Field experiments showed that the system was easy to maintain and could be used to monitor chemical accidents.

Synthetic organic chemicals are present in environmental compartments as complex mixtures and therefore their potential effects are difficult to predict. In this study, in vitro bioassays using wild-type fish and rat hepatoma cell lines and their corresponding recombinant cell systems were used to evaluate 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-like activity in extracts of sediments collected from rivers of the Czech Republic. All the sediment extracts elicited statistically significant responses in all the cell lines tested. For most sediment extracts, a complete dose-response relationship was obtained. The maximal efficacy of the samples was between 57 and 143% of the maximal induction elicited by TCDD. Greater responsiveness, sensitivity, and reproducibility were observed for recombinant than wild-type cells. Cell line-specific differences in the sensitivity to compounds present in the complex sediment extracts were observed. The TCDD equivalents (TCDD-EQs) determined from the different cell bioassays were correlated. Greater concentrations of TCDD-EQs were obtained with fish cell lines. The TCDD-EQs calculated from the results of chemical analysis of toxic equivalents (TEQs) were in good agreement with those determined by bioassays; the arly hydrocaron receptor (AhR)-effects of the identified chemicals appear to be generally additive. This indicates that most of the TCDD-like activity was accounted for by the compounds identified and quantified by instrumental analysis. Fractionation along with mass-balance calcu- lations allowed identification of the active fractions and classes of compounds. Polycyclic aromatic hydrocarbons (PAHs) were found to be responsible for most of the AhR-mediated activity in sediments. Keywords—In vitro bioassays 2,3,7,8-Tetrachlorodibenzo- p-dioxin Polycyclic aromatic hydrocarbons Organochlorines Dioxin-like activity

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.

韓国で採取された人体脂肪から検出された残留性有機塩素系化合物のうち, 一番高い残留レベルを示したDDTsは平均828ng・g-1, 濃度範囲は118～7800ng・g-1で検出された。DDTの代謝産物の中で, 総DDTsの濃度に対するp, p'-DDEの寄与は90%以上を占めている-方, p, p'-DDTとp, p'-DDDの寄与はそれぞれ5.8%と0.7%であった。p, p'-DDE/p, p'-DDTの比率は15と計算され, 今後, 韓国人体内のDDTs濃度は次第に減少することが予想された。-方, HCHsの総平均濃度は143ng・g-1で検出されており, そのうちβ-HCHが占める割合は98.6%であった。総HCHs濃度に対するα-HCHとγ-HCHの寄与はごくわずかであり, それぞれ0.9%と0.4%を占めていた。また, 諸外国の総HCHs濃度に対するβ-HCHの割合との比較から韓国内のHCHsの使用禁止の事実を間接的に検証することができた。本研究の対象化合物の中, 最も低い残留レベルを示したHCBは平均19ng・g-1そして濃度範囲は7.3～86ng・g-1で検出された。体内脂肪組織中PCBsの検出濃度範囲は61～810ng・g-1であり, 主に残留している異性体はIUPACNo.153, 138, 180であることが確認できた。地域による濃度差の検討によってソウルと晋州地域から採取された体脂肪中のHCHsとDDTsの濃度の間に有意な濃度差が見られたが, これは居住地域による違いより試料の年齢組成の差から起因したものと判断された。馬山地域から採取した母乳試料中の人工有機塩素系化合物の濃度順位は, DDTs (平均; 287ng・g-1) >PCBs (220ng・g-1) >HCHs (57ng・g-1) >HCB (12ng・g-1) の順であり, その濃度順位とレベルは脂肪組織と比べて大差なかった。また, 出産による濃度の減少傾向は若干見られたが, 有意ではなかった。他方, 母乳の摂取による乳児の一日摂取量を検討した結果, HCHsは0.27μg/kg/day, DDTsは1.38, HCBは0.06及びPCBsは1.06と見積もられた。これはFAO/WHOによるADI (一日許容摂取量) 以下のレベルであり, NOEL/一日摂取量の比率の検討の結果, 韓国人の母乳中の有機塩素系農薬やPCBsの残留レベルはある程度安全な水準であることが確認できた。

韓国内で入手した, 市販魚試料の分析の結果, 各化合物の濃度レベルはDDTs>PCBs>HCHs>HCB>PCDFs>PCDDsの順であった。そして魚類から検出された各化合物の濃度は魚類の脂肪含有量と有意な相関性を示した。すなわち, 全般に脂肪量が多いサバとタチウオの濃度がイシモチとタラのそれより高い傾向を示した。市販魚類のPCDDs/DFsの各同族体の組成は低塩素のPCDDs/DFsのほうがより多く検出されており, とくに総PCDDs/DFs-TEQ濃度に対する2, 3, 4, 7, 8-PeCDFの寄与率は42%と計算された。このことから韓国人において食品としての魚類は2, 3, 4, 7, 8-PeCDFのような低塩素のPCDDs/DFsの主な供給源の一つであると判断した。韓国人の魚介類の摂取量は欧米諸国とくらべ比較的多いため, 魚類を通じてこれらの有機塩素系化合物が多く摂取されていると予想されたが, 意外に有機塩素系農薬やPCBsの摂取量は他の国と比べ, 類似するレベルであった。しかし, PCDDs/DFsの場合は, 日本を除いた諸外国のレベルと比べ高いことが確認できた。以上のことから韓国人にとって魚類の摂取はPCDDs/DFsの供給源として主要な割合を占めていることが判断された。

Hexachlorocyclohexanes (HCHs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs) were determined in human adipose tissue samples collected from western Kyungnam, Korea. The residue levels of organochlorine compounds were in the order of DDTs followed by PCBs > HCHs > HCB > PCDDs/DFs. The mean concentrations of 2,3,7,8-TeCDD in male and female tissues were 2.8 and 1.7 pg.g-1 on lipid weight basis, respectively. No significant difference was found in the residue levels of PCDDs/DFs between sexes. In contrast, PCBs and DDTs showed a significant difference between sexes. Unlike the age trend observed for HCHs, PCBs and DDTs, PCDDs/DFs revealed a constant or rather decreasing pattern with increasing age. This is the first report on PCDDs/DFs contamination in human adipose tissue from Korea. Organochlorine concentrations in human adipose tissues from western Kyungnam were generally much lower than those of other countries.

Concentrations and accumulation profiles of PCDDs/DFs and coplanar-PCBs (co-PCBs) in aquatic biota (e.g., plankton, shellfish, benthic invertebrate, and fish) and sediment from Tokyo Bay were examined to elucidate the relationship between bioaccumulation and trophic level in the food web as determined by the stable nitrogen isotope analysis. Bioaccumulation patterns of PCDDs/DFs and co-PCBs varied greatly among congeners. Accumulation patterns of PCDDs/DFs and co-PCBs are not solely explained by their physicochemical properties. Biota-sediment accumulation factors (BSAFs) for co-PCBs in biota from Tokyo Bay were significantly greater than those of PCDDs/DFs. Furthermore, the slopes of the plots of delta15N and BSAF values and water solubility of 2,3,7,8-substituted PCDDs/DFs and co-PCBs were highly correlated. The results of our study would provide the valuable information to understand the accumulation properties of PCDDs/DFs and co-PCBs that can be used as a scientific basis to determine the sediment quality criteria of PCDDs/DFs and co-PCBs.

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs) were detected in waterfowl such as common cormorants, tufted ducks, and their prey, namely fish and bivalves from Lake Shinji, Japan. The concentration of total PCDDs/DFs-TEQ was found to be higher in the muscle tissues of common cormorants than in those of tufted ducks. The results of hierarchical cluster analysis implied that the residue distribution pattern of PCDD/DF homologues was considerably different between these two species. Furthermore, biomagnification factors (BMFs) were estimated from bivalves as prey to tufted duck muscles as target organs. Despite the highest concentrations of 1,3,6,8- and 1,3,7,9TeCDD in tufted ducks and their prey, however, the BMFs of these isomers were calculated to be lower than those of the toxic 2,3,7,8-substituted PCDDs/DFs. On the other hand, log BMF of toxic 2,3,7,8-substituted PCDDs/DFs were significantly higher for lower chlorinated isomers than those of the higher chlorinated isomers. The biota-sediment accumulation factors (BSAFs) of PCDDs/DFs were also estimated using shijimi clam and fish samples against sediment from Lake Shinji. The average BSAFs were estimated and ranged from 4:0 � 10 � 3 to 2:2 � 10 � 1 and 2:0 � 10 � 4 to 2:0 � 10 � 1 for bivalve and fish samples, respectively. Based on calculated BMFs and BSAFs, the total PCDD/DF-TEQ levels in the tufted duck were estimated to have been lowest (2.0 pg TEQ/g dry weight basis) in 1947 and highest (9.8 pg TEQ/g) in 1971. 2002 Elsevier Science Ltd. All rights reserved.