BACKGROUND: Over the past few decades, the Japanese Ministry of the Environment has been biomonitoring dioxins in the general Japanese population and, in response to public concerns, has taken measures to reduce dioxin exposure. The objectives of this study were to assess the current dioxin dietary intake and corresponding body burden in the Japanese and compare Japanese dioxin data from 2011 to 2016 and 2002-2010 surveys. We also examined the relationship between blood dioxins and health parameters/clinical biomarkers. METHODS: From 2011 to 2016, cross-sectional dioxin surveys were conducted on 490 Japanese (242 males and 248 females, aged 49.9 ± 7.6 years) from 15 Japanese prefectures. Blood (n = 490) and food samples (n = 90) were measured for 29 dioxin congeners including polychlorinated dibenzo-para-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs) using gas chromatography coupled with high-resolution mass spectrometry. Using the 2006 World Health Organization toxic equivalence factors, the toxic equivalents (TEQs) were calculated. Clinical biomarkers and anthropometric parameters were also measured and information on lifestyle behaviours collected. Data imputations were applied to account for blood dioxins below the detection limit. RESULTS: The median (95% confidence interval or CI) blood levels and dioxin dietary intake was respectively 9.4 (8.8-9.9) pg TEQ/g lipid and 0.3 (0.2-0.4) pg TEQ/kg body weight/day. The median blood dioxin level in the 2011-2016 survey was found to have decreased by 41.3% compared to the 2002-2010 surveys. Participants who were older were found to be more likely to have higher dioxin levels. Blood dioxins were also significantly associated with body mass index, triglycerides, docosahexaenoic acid, eicosapentaenoic acid, and dihomo-gamma-linoleic acid levels in blood. Furthermore, associations between blood dioxin and dietary dioxin intake were evident in the unadjusted models. However, after adjusting for confounders, blood dioxins were not found to be associated with dietary dioxin intake. CONCLUSIONS Blood dioxin levels declined over the past decade. This study showed that the measures and actions undertaken in Japan have possibly contributed to these reductions in the body burden of dioxins in the Japanese population.
Adult ; Aged ; Analysis of Variance ; Biomarkers ; blood ; Body Mass Index ; Cross-Sectional Studies ; Diet ; Dioxins ; analysis ; Environmental Exposure ; analysis ; Environmental Monitoring ; methods ; Female ; Food ; Food Analysis ; Food Contamination ; analysis ; Gas Chromatography-Mass Spectrometry ; Humans ; Japan ; Male ; Middle Aged ; Surveys and Questionnaires ; Young Adult

We live in a world where daily exposure to environmental chemicals is inevitable. Many studies point to environmental chemicals a major cause of neurological diseases. Properly intervening in and managing the exposure requires up-to-date information about neurotoxic chemicals that may lead to neurological disorders. The recent literature on the neurotoxic effects of environmental chemicals was reviewed, including both animal and human studies. Parkinson's disease, Alzheimer's disease and autism are closely associated with environmental chemicals such as polychlorinated biphenys (PCBs), dioxins, polybrominated biphenyl ethers (PBDE), and perfluoroalkyls. There is strong evidence linking environmental chemical exposure to neurodevelopmental and neurodegenerative diseases. In particular, it is important to pay close attention to a high risk-age group where the window of exposure is critical to causing neurological disease.
Alzheimer Disease ; Animals ; Autistic Disorder ; Dioxins ; Endocrine Disruptors ; Ether ; Ethers ; Humans ; Nervous System Diseases ; Neurodegenerative Diseases ; Parkinson Disease

OBJECTIVETo assess the net health effect caused by the consumption of specific marine species based on Benefit-Risk Analysis for Foods (BRAFO)-tiered approach.

METHODSTwenty species were collected from the Zhoushan Archipelago, China. Concentrations of n-3 long-chain polyunsaturated fatty acids, methyl mercury (MeHg), and dioxin-like compounds (DLCs) in the samples were analyzed for benefit risk assessment based on BRAFO-tiered approach.

RESULTSBased on the BRAFO-tiered approach, reference scenario (no intake) and alternative scenario (intake of specific species of 200 g/week) were determined. The exposure to MeHg/DLCs via alternative scenario of all studied species did not exceed provisional tolerable weekly/monthly intake. However, the adult population with high DLCs exposure in China would significantly exceed the upper limit of DLCs via an additional alternative scenario of some species such as Auxis thazard. The results of deterministic computation showed that alternative scenario of all studied species generated clear net beneficial effects on death prevention and child IQ gain.

CONCLUSIONThe alternative scenario of all studied species could be recommended to population with average DLCs exposure, and the reference scenario of species with relatively high DLCs concentration could be recommended to population exposed to high DLCs.

Animals ; China ; Dioxins ; analysis ; Environmental Pollutants ; analysis ; Fatty Acids, Omega-3 ; analysis ; Fishes ; Humans ; Methylmercury Compounds ; analysis ; Risk Assessment ; Seafood ; analysis ; Species Specificity

BACKGROUND: Aryl hydrocarbon receptor (AhR), a ligand-dependent transcription factor, binds to a wide variety of synthetic and naturally occurring compounds. AhR is involved in the regulation of inflammatory response during acute and chronic respiratory diseases. We investigated whether nuclear receptor coactivator 7 (NCOA7) could regulate transcriptional levels of AhR target genes and inflammatory cytokines in 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-treated human bronchial epithelial cells. This study was based on our previous study that NCOA7 was differentially expressed between normal and chronic obstructive pulmonary disease lung tissues. METHODS: BEAS-2B and A549 cells grown under serum-free conditions were treated with or without TCDD (0.15 nM and 6.5 nM) for 24 hours after transfection of pCMV-NCOA7 isoform 4. Expression levels of cytochrome P4501A1 (CYP1A1), IL-6, and IL-8 were measured by quantitative real-time polymerase chain reaction. RESULTS: The transcriptional activities of CYP1A1 and inflammatory cytokines were strongly induced by TCDD treatment in both BEAS-2B and A549 cell lines. The NCOA7 isoform 4 oppositely regulated the transcriptional activities of CYP1A1 and inflammatory cytokines between BEAS-2B and A549 cell lines. CONCLUSION: Our results suggest that NCOA7 could act as a regulator in the TCDD-AhR signaling pathway with dual roles in normal and abnormal physiological conditions.
Cell Line ; Cytochrome P-450 CYP1A1* ; Cytochromes ; Cytokines ; Dioxins ; Epithelial Cells ; Humans ; Inflammation* ; Interleukin-6 ; Interleukin-8 ; Lung ; Pulmonary Disease, Chronic Obstructive ; Real-Time Polymerase Chain Reaction ; Receptors, Aryl Hydrocarbon ; Tetrachlorodibenzodioxin ; Transcription Factors ; Transfection

Dioxins are a most toxic compound ever studied by human until today. Their significant health effects involved all ranges of age, including infants due to exposure to contaminated breast milk. The objective of the study was to appraise the status of dioxin contamination in breast milk among postnatal mothers live in urban and suburban areas in Klang Valley. It was conducted as a cross sectional study involving 101 postnatal mothers who came for their infant second hepatitis B vaccination. The samples were analysed using High Resolution Gas Chromatography (HRGC) following the USEPA Method 8290. About 70.3% of the samples were found detected with dioxin congeners. More suburban mothers have positive breast milk dioxins compared to urban mothers, 100.0% and 67.0% respectively. Significant associated factors include high fat daily intake (p=0.013), high milk daily intake (p= 0.044), high meat daily intake (p=0.001), body mass index more than 30 kg/m2 (p=0.005), and body fat % of more than 26% (p=0.046). In conclusion, amount daily intake of fat diet, meat, milk, body mass index and body fat are significant associated factors for the present of dioxins in breast milk among postnatal mothers in Klang Valley. More suburban mothers contain dioxins in their breast milk, which poses higher risk of health problems among their infants. A comprehensive study need to be conducted and regular followup need to be established in monitoring the future severity of maternal breast milk contamination to ensure the health of the next generations.
Dioxins ; Milk, Human ; Suburban Population ; Breast Feeding

OBJECTIVETo explore the role of histone H3 acetylation in cleft palate induced by 2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin (TCDD) in C57BL/6J mice, and its mechanism.

METHODSOn gestation day 10 (GD10), 36 pregnant mice were randomly divided into two groups as the treated group(n = 18) and the control group( n = 18). The mice in the treated group received intragastric administration with TCDD 28 μg/kg, while the mice in the control group received equivalent corn oil. The pregnant mice were sacrificed on GD13. 5, GD14. 5 and GD15. 5, collecting fetal palates to determine the activities of histone acetyltransferases (HATs) by Colorimetric and the expression level of acetylated histone H3 (Acetylated histone H3, Ac-H3) by Western-blot.

RESULTSThe activity of HATs was 0.409 7 ± 0.0147, 0.522 3 ± 0.017 1 and 0.643 5 ± 0.013 9 in control group on GD13.5, GD14.5 and GD15.5; 0.865 0 ± 0.0129, 0.719 1 ± 0.017 8 and 0.551 2 ± 0.016 8 in TCDD group. The activity of HATs in TCDD group was higher than that in control group on GD13. 5, GD14. 5, showing significantly difference between the two groups (t = - 56. 932, t = - 19. 516, P < 0.01); however, the activity of HATs in TCDD group was significantly lower than that in control group on GD15. 5 (t = 10. 382, P < 0.01). The expression level of Ac-H3 was 0.745 0 ± 0.113 5, 1.055 9 ± 0.249 4 and 1.795 5 ± 0.081 9 in control group on GD13. 5, GD14. 5 and GD15. 5; while 1.4490 ± 0. 1460, 1. 641 8 ± 0.099 7 and 1. 512 1 ± 0. 150 2 in TCDD group. The expression of Ac-H3 in TCDD group was higher than that in control group on GD13. 5, GD14. 5, showing significantly difference( t = -6. 593, -3. 779, P <0. 01, P <0.05) ; However, the expression of Ac-H3 in TCDD group was statistically lower than that in control group (t = 2. 870, P <0. 05).

CONCLUSIONThe acetylation of histone H3 was involved in the cleft palate of C57BL/6J mice induced by TCDD, which may be one of the mechanisms in TCDD-induced cleft palate.

Acetylation ; drug effects ; Acetyltransferases ; metabolism ; Animals ; Cleft Palate ; chemically induced ; metabolism ; Dioxins ; Female ; Fetus ; Histones ; metabolism ; Humans ; Mice ; Mice, Inbred C57BL ; Polychlorinated Dibenzodioxins ; Pregnancy ; Random Allocation ; Teratogens

OBJECTIVETo investigate contamination levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in human breast milk from Beijing residents, and evaluate the human body burden of PCDD/Fs and dl-PCBs of general population.

METHODSA total of 110 human milk samples were collected from 11 regions in Beijing in 2007. After 11 pooled samples were made, concentrations of PCDD/Fs and dl-PCBs in breast milk pooled samples were measured by a high resolution gas chromatography - high resolution mass spectrometry (HRCG-HRMS) with isotope dilution.

RESULTSFor congeners of PCDD/Fs and dl-PCBs in human breast milk from Beijing, the highest content of congeners was octachlorodibenzo-p-dioxin (OCDD), polychlorinated biphenyl (PCB)-118, and PCB-105 with the median of 20.6 pg/g fat, 4.07 ng/g fat and 1.63 ng/g fat, respectively. The concentration median of total dioxins in 11 pooled human milk samples from Beijing was 7.4 pg TEQ/g fat. The highest was 13.5 pg TEQ/g fat from Tongzhou, and the lowest was 4.3 pg TEQ/g fat from Pinggu.

CONCLUSIONThe contamination level of PCDD/Fs and dl-PCBs in human milk from Beijing is relatively low. However, with the rapid industrialization in China, the human body burden of PCDD/Fs and dl-PCBs will be likely to rise. Thus, further studies should be conducted to continuously monitor the trend of contamination level.

Adult ; Benzofurans ; analysis ; Body Burden ; China ; Dioxins ; analysis ; Environmental Pollutants ; Female ; Humans ; Maternal Exposure ; Milk, Human ; chemistry ; Polychlorinated Biphenyls ; analysis ; Polychlorinated Dibenzodioxins ; analogs & derivatives ; analysis ; Polymers ; analysis ; Young Adult

Benzofurans ; analysis ; chemistry ; Dibenzofurans, Polychlorinated ; Dioxins ; analysis ; chemistry ; Humans ; Occupational Exposure ; prevention & control

OBJECTIVETo study correlations of polychlorinated biphenyls (PCBs), DIOXIN, and polybrominated diphenyl ethers (PBDE) with thyroid stimulating hormone(TSH) in children, and assess the impact on children's health.

METHODSThree hundred and sixty nine children aged from 6 to 8, including 195 from Luqiao, the computer E-waste recycling area, and 174 from Longyou, the control area, were selected for this investigation to elucidate the correlation of PCBs, DIOXIN, and PBDE with TSH in children's blood samples. The children had a physical examination and their blood levels of PCBs, DIOXIN, PBDE, and TSH were detected after sample collection.

RESULTSIn the E-waste recycling area, the contents of PCBs, PBDE, DIOXIN, and TSH in the blood samples of children were 484.00 ± 84.86 ng·g(-1) lipid weight, 664.28 ± 262.38 ng·g(-1) lipid weight, 26.00 ± 19.58 ng·g(-1) lipid weight and 1.88 ± 0.42 μIU/mL (serum) respectively, while in the control area, the PCBs, PBDE, DIOXIN, and TSH contents were 255.38 ± 95 ng·g(-1) lipid weight, 375.81 ± 262.43 ng·g(-1) lipid weight, 39.64 ± 31.86 ng·g(-1) lipid weight, and 3.31±1.04 μIU/mL respectively.

CONCLUSIONThe health status of children in the control area are better than that in the contaminated area. Among children who are exposed to persistent organic pollutants, the pollutant content increases significantly in their serum, and the distribution of TSH levels in their bodies are also affected.

Child ; China ; Dioxins ; blood ; chemistry ; Electronic Waste ; Environmental Pollutants ; blood ; chemistry ; Female ; Halogenated Diphenyl Ethers ; blood ; chemistry ; Humans ; Male ; Polychlorinated Biphenyls ; blood ; chemistry ; Recycling ; Refuse Disposal ; methods ; Thyrotropin ; blood

Acting as hormone mimics or antagonists in the interaction with hormone receptors, endocrine disrupting chemicals (EDCs) have the potentials of disturbing the endocrine system in sex steroid hormone-controlled organs and tissues. These effects may lead to the disruption of major regulatory mechanisms, the onset of developmental disorders, and carcinogenesis. Especially, among diverse EDCs, xenoestrogens such as bisphenol A, dioxins, and di(2-ethylhexyl)phthalate, have been shown to activate estrogen receptors (ERs) and to modulate cellular functions induced by ERs. Furthermore, they appear to be closely related with carcinogenicity in estrogen-dependant cancers, including breast, ovary, and prostate cancers. In in vivo animal models, prenatal exposure to xenoestrogens changed the development of the mouse reproductive organs and increased the susceptibility to further carcinogenic exposure and tumor occurence in adults. Unlike EDCs, which are chemically synthesized, several phytoestrogens such as genistein and resveratrol showed chemopreventive effects on specific cancers by contending with ER binding and regulating normal ER action in target tissues of mice. These results support the notion that a diet containing high levels of phytoestrogens can have protective effects on estrogen-related diseases. In spite of the diverse evidences of EDCs and phytoestrogens on causation and prevention of estrogen-dependant cancers provided in this article, there are still disputable questions about the dose-response effect of EDCs or chemopreventive potentials of phytoestrogens. As a wide range of EDCs including phytoestrogens have been remarkably increasing in the environment with the rapid growth in our industrial society and more closely affecting human and wildlife, the potential risks of EDCs in endocrine disruption and carcinogenesis are important issues and needed to be verified in detail.
Adult ; Animals ; Benzhydryl Compounds ; Breast ; Diet ; Dioxins ; Endocrine Disruptors ; Endocrine System ; Estrogens ; Female ; Genistein ; Humans ; Mice ; Models, Animal ; Ovary ; Phenols ; Phytoestrogens ; Prostatic Neoplasms ; Receptors, Estrogen ; Stilbenes