Dioxins levels in human blood after implementation of measures against dioxin exposure in Japan

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.

Environmental Endocrine Disruptors and Neurological Disorders

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.

Toxicidade equivalente da atmosfera por dioxinas, furanos e bifenilas policloradas,com uso de duas técnicas de coleta, passiva e ativa / Equivalent toxicity of the atmosphere for dioxins, furans and polychlorinated biphenyls, using two air sampling techniques, passive and active

Introdução: Dioxinas, furanos e bifenilas policloradas são poluentes tóxicos para a saúde humana incluindo riscos de incidência de cânceres, efeitos de neurodesenvolvimento, lesões dérmicas, cloroacne. Estes compostos são poluentes orgânicos persistentes (POPs) que podem ser transportados de longas distâncias da fonte de emissão e se bioacumular em ecossistemas. A atmosfera poluída foi recentemente classificada como carcinogênica para os seres humanos pela Organização Mundial da Saúde, mostrando a importância de sua caracterização, principalmente para compostos tóxicos. Entretanto, técnica de coleta ativa tem custo elevado para POPs, e existem poucos estudos de calibração que validem a substituição. Objetivos: Avaliar a toxicidade equivalente da atmosfera por dioxinas, furanos e bifenilas cloradas, utilizando técnicas de coleta ativa e passiva, e verificar gradiente de concentração nos ambientes urbano, urbano/industrial e de background. Método: Amostras de ar foram coletadas, utilizando coletores ativos e passivos, durante dois períodos consecutivos de quatro meses: de setembro a dezembro de 2014 (período 1) e de maio a agosto de 2015 (período 2) em três cidades de São Paulo, SP, em ambientes urbano, urbano/industrial e de background. Todas as amostras foram extraídas com solução de tolueno:acetona (9:1) em Soxhlet por 24 h e padrões marcados (13C12-PCDD/Fs e 13C12-PCBs) foram adicionados em cada amostra antes do processo de extração. Os extratos foram purificados em coluna de sílica mista (40 por cento H2SO4 e 10 por cento AgNO3) seguida por coluna de alumina. O procedimento analítico foi realizado utilizando HRGC/HRMS (High Resolution Gas Chromatograph/High Resolution Mass Spectrometer) operando em ionização de impacto de elétrons com energia de 35 eV no modo SIM (Select Ion Monitoring) e resolução de 10.000. Resultados mostraram que: (1) existe variação sazonal para concentrações de PCDD/Fs no ar entre os períodos 1 e 2 (p=0,03), enquanto as concentrações de dl-PCBs não foram estatisticamente diferentes nestes períodos (p=0,52); (2) existe gradiente de concentração de PCDD/Fs e dl- PCBs que aumenta na seguinte ordem: background

Introduction: Dioxins, furans and polychlorinated biphenyls are toxic pollutants for human health including risks of cancer incidence, neurodevelopmental effects, dermal lesions, chloracne. These compounds are persistent organic pollutants (POPs) that can be transported to long distances from the emission source and they are bioaccumulated in ecosystems. Recently, the outdoor air pollution were classified as carcinogenic to humans by the World Health Organization, showing the importance of its characterization for toxic compounds. However, active air monitoring has a high cost for POPs, and there is a few calibration studies which support that substitution. Objective: To assess the equivalent toxicity of the atmosphere regarding the measurement of dioxins, furans and polychlorinated biphenyls, using active and passive air samplers, and to evatuate the contrasting concentrations at urban, urban/industrial and background sites. Method: Air samples were collected, using active and passive samplers, over two consecutive periods of four months: from September to December 2014 (period 1) and from May to August 2015 (period 2) at three cities in São Paulo, SP, covering urban, urban/industrial and background sites. All samples were extracted with toluene:acetone (9:1) in a Soxhlet apparatus for 24 hours and surrogate standards (13C12-PCDD/F and 13C12-PCBs) were spiked on each sample media prior to extraction procedure. The extracts were purified on an silica column (40 per cent H2SO4 and 10 per cent AgNO3) followed by an alumina column. The analytical procedure was carried out using HRGC/HRMS (High Resolution Gas Chromatograph/High Resolution Mass Spectrometer) operating in electron impact ionization with an energy of 35 eV in SIM (selected ion monitoring) mode and 10.000 resolution power. Results show that (1) there are seasonal variations for PCDD/F concentrations in air between period 1 and 2 (p=0.03), whereas dl-PCB levels were not statistically different (p=0.52) in those periods. (2) PCDD/F and dl-PCB air levels are in the following order: background

Suburban Breastfed Infants In Klang Valley Are At Higher Risk Of Dioxins Toxicity

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.

The Benefit Risk Assessment of Consumption of Marine Species Based on Benefit-Risk Analysis for Foods (BRAFO)-tiered Approach / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To assess the net health effect caused by the consumption of specific marine species based on Benefit-Risk Analysis for Foods (BRAFO)-tiered approach.</p><p><b>METHODS</b>Twenty 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.</p><p><b>RESULTS</b>Based 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.</p><p><b>CONCLUSION</b>The 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.</p>

Regulation of CYP1A1 and Inflammatory Cytokine by NCOA7 Isoform 4 in Response to Dioxin Induced Airway Inflammation / 결핵및호흡기질환

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.

Effects of endocrine disruptors in the development of the female reproductive tract / Efeitos dos desreguladores endócrinos no desenvolvimento do trato reprodutivo feminino

Environmental agencies have identified a growing number of environmental contaminants that have endocrine disrupting activity, and these can become a major public health problem. It is suggested that endocrine disruptors could account for the higher-than-expected increase in the prevalence of some non-communicable diseases, such as obesity, diabetes, thyroid diseases, and some cancers. Several endocrine Disrupting Chemicals (EDCs), such as pesticides, bisphenol A, phthalates, dioxins, and phytoestrogens, can interact with the female reproductive system and lead to endocrine disruption. Initially, it was assumed that EDCs exert their effects by binding to hormone receptors and transcription factors, but it is currently known that they may also alter the expression of enzymes involved in the synthesis or catabolism of steroids. Biomonitoring studies have identified these compounds in adults, children, pregnant women, and fetuses. Among the diseases of the female reproductive tract associated with EDCs exposure are the following: precocious puberty, polycystic ovary syndrome, and premature ovarian failure. The different populations of the world are exposed to a great number of chemicals through different routes of infection; despite the various available studies, there is still much doubt regarding the additive effect of a mixture of EDCs with similar mechanisms of action.

As diversas agências de controle ambiental têm identificado um crescente número de contaminantes ambientais que apresentam atividade de desregulador endócrino e estes poderão se tornar um dos maiores problemas de saúde pública. Sugere-se que os Desreguladores Endócrinos (EDCs) poderiam justificar o aumento na prevalência de algumas doenças não transmissíveis acima do esperado, como, por exemplo, obesidade, diabetes, doenças tireoidianas e alguns tipos de cânceres. Vários EDCs, como pesticidas, bisfenol A, ftalatos, dioxinas e fitoestrógenos, podem interagir com o sistema reprodutivo feminino e levar à desregulação endócrina. Inicialmente, supunha-se que os EDCs exercessem seus efeitos através da ligação com receptores hormonais e fatores de transcrição, mas, atualmente, sabe-se que também podem alterar a expressão de enzimas envolvidas na síntese ou no catabolismo dos esteroides. Estudos de biomonitoramento têm identificado esses compostos em adultos, crianças, gestantes e em fetos. Entre as patologias do trato reprodutor feminino associadas à exposição aos EDCs, destacam-se: puberdade precoce, síndrome dos ovários policísticos e falência ovariana prematura. As diversas populações estão expostas a um grande número de substâncias químicas, através de diferentes vias de contaminação. Apesar dos diferentes estudos disponíveis, ainda permanece uma grande dúvida sobre o efeito aditivo de uma mistura de EDCs com similar mecanismo de ação.

The role of histone H3 acetylation on cleft palate in mice induced by 2, 3, 7, 8-tetrachlorodibenzopdioxin / 中华整形外科杂志

<p><b>OBJECTIVE</b>To 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.</p><p><b>METHODS</b>On 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.</p><p><b>RESULTS</b>The 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).</p><p><b>CONCLUSION</b>The 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.</p>

Dioxins and polychlorinated biphenyls concentrations in Larus dominicanus. Case study: Marambaia island, Sepetiba bay, Rio de Janeiro State, Brazil / Concentrações de dioxinas e bifenilas policloradas em Larus dominicanus. Estudo de caso: ilha da Marambaia, baía de Sepetiba, Estado do Rio de Janeiro, Brasil

Seabirds play a significant role as bioindicators: they are conspicuous, relatively easy to observe, well-established studied group of organisms, and in the focus of public interest due to pollution in aquatic ecosystem. Systematically, a significant number of man-made chemicals have been introduced in the marine environment and represent the major problem arising in the development worldwide. Many of these chemical contaminants are persistent, known to bioaccumulate and biomagnify through the aquatic food web, affecting species associated with aquatic systems. Dioxins [polychlorinated dibenzo-p-dioxins (PCDD), dibenzofurans (PCDF)] and polychlorinated biphenyls (PCB) concentrations were measured in Kelp gull Larus dominicanus collected from 2006 to 2011 on Marambaia Island, Sepetiba Bay, Rio de Janeiro State, Brazil. Detectable liver concentrations of PCDD Fs-1 and PCBs were found in all samples analyzed. These represent some of the first measurements of PCDD Fs-1 and PCBs in seabirds from this area. Although levels of these contaminants in the tested species currently appear to fall below critical values, a continuous and systematic monitoring on these compounds becomes essential and desirable to not express toxic values in the future.

Aves marinhas desempenham uma função significativa como bioindicadores: elas são conspícuas, relativamente fáceis de observar, grupos de organismos de estudo bem estabelecidos e no foco de interesse público devido à poluição no ecossistema aquático. Sistematicamente, um número significativo de produtos químicos sintéticos vêm sendo introduzidos no ambiente marinho, representando um dos principais problemas que se coloca no desenvolvimento em todo o mundo. Muitos desses contaminantes químicos são persistentes, conhecidos por bioacumular e biomagnificar através de suas movimentações na cadeia alimentar, afetando espécies associadas aos sistemas aquáticos. Concentrações de dioxinas [dibenzo-p-dioxinas policloradas (PCDD), dibenzofuranos (PCDF)] e bifenilas policloradas (PCB) foram medidas em gaivotões Larus dominicanus coletadas de 2006 a 2011 na Ilha da Marambaia, Baía de Sepetiba, Rio de Janeiro, Brasil. Estes dados representam algumas das primeiras medições de PCDD Fs-1 e PCBs em aves marinhas nesta área estudada. Embora os níveis destes contaminantes na espécie testada apresentarem níveis abaixo dos valores críticos, o monitoramento contínuo, sistemático, torna-se imprescindível e desejável para que estes compostos não expressem no futuro valores tóxicos.

The human body burden of polychlorinated dibenzo-p-dioxins and dibenzofurans and dioxin-like polychlorinated biphenyls in residents' human breast milk from Beijing in 2007 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To 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.</p><p><b>METHODS</b>A 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.</p><p><b>RESULTS</b>For 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.</p><p><b>CONCLUSION</b>The 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.</p>

Diverse animal models to examine potential role(s) and mechanism of endocrine disrupting chemicals on the tumor progression and prevention: Do they have tumorigenic or anti-tumorigenic property? / 한국실험동물학회지

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.

Correlations of PCBs, DIOXIN, and PBDE with TSH in children's blood in areas of computer E-waste recycling / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To 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.</p><p><b>METHODS</b>Three 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.</p><p><b>RESULTS</b>In 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.</p><p><b>CONCLUSION</b>The 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.</p>

Toxicología de las dioxinas y su impacto en la salud humana / Dioxins toxicology and its impact in human health

Las dioxinas son contaminantes de síntesis que se forman de manera espontánea en diversos procesos industriales. Son compuestos organoclorados muy estables en el medio ambiente, capaces de permanecer en los tejidos humanos y animales; y por ello hacen bioacumulación, lo que facilita la presentación de toxicidad crónica, dentro de la que se destaca la carcinogenicidad, la mutagenicidad y el efecto disruptor endocrino. Se hace referencia a las características físicoquímicas de estos compuestos, a su toxicodinamia y efectos adversos, para finalmente,relacionar la toxicidad de estos compuestos con la salud humana y con la responsabilidad de producir alimentos inocuos para el ser humano...

The levels of dioxin in 60 human breast milk samples and the exposure risk factor analysis in Shenzhen / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-furans (PCDD-Fs) in human breast milk of the mothers who lived in non-directly persistent organic pollutants (POPs) polluted area in Shenzhen, and the correlation of exposure risk factor was analyzed.</p><p><b>METHODS</b>From July to November in 2007, 60 primiparas by vaginal delivery after parturition 3 weeks to 2 months were sampled for breast milk who aged from 20 - 34 years old and has lived in Shenzhen non-directly POPs polluted areas over 5 years. PCDD-Fs were extracted from the frozen-dried samples with accelerated solvent extraction (ASE), cleaned up by fluid management system (FMS) and quantified by high-resolution gas chromatography-high resolution mass spectrometry (HRGC-HRMS) using isotope dilution methodology. TEQ were calculated. The correlation relationship among infant's birth weight and length, participatory's dietary, age, inhabitation period, environment and the body burden of PCDD-Fs in mother was statistically analyzed by SPSS 13.0.</p><p><b>RESULTS</b>The participants aged from 20 - 34 years old (28 years on average) and lived in Shenzhen for 5 - 29 years (10 years on average). The concentration of PCDD-Fs in 60 breast milk samples were 26.957 143 - 669.583 333 pg/g fat (mean: 7.224 817 pg/g fat, median: 84.176 062 pg/g fat), and TEQ-PCDD-Fs in samples were 2.420 793 - 29.014 277 pg/g fat (mean: 8.645 992 pg/g fat, median: 7.751 804 pg/g fat). 2, 3, 4, 7, 8-PeCDF, 1, 2, 3, 7, 8-PeCDD, 2, 3, 7, 8-TCDD were the dominant contributors to the total TEQ, which were 3.691 654 pg/g fat (42.689 378%), 2.478 315 pg/g fat (28.652 356%), and 0.980 995 pg/g fat (11.343 995%) respectively. Significant positive correlations were found among age (r = 0.26, P < 0.05), inhabitation period (r = 0.49, P < 0.05), the consumption of fish (r = 0.37, P < 0.05) and the concentrations of TEQ-PCDD-Fs in the study.</p><p><b>CONCLUSION</b>The levels of dioxin chemicals in the breast milk samples in non-directly POPs polluted areas of Shenzhen are high. Significant positive correlations were found among age, inhabitation period, the consumption of fish and the concentration of PCDD-Fs.</p>

Transient mass transfer modeling and simulation of polybrominated diphenyl ethers combustion in incinerators

In this paper, modeling and simulation of combustion process for polybrominated diphenyl ethers in rotary kilns has been investigated. Proper formula is found for the solid wastes which contain polybrominated diphenyl ethers and then combustion process is simulated by considering possible reactions, appropriate dimensions and operating conditions for rotary kiln and necessary relations for reaction rates. The software of MATLAB is used for the simulation. The mass variations for solid waste, outlet gas and its components are calculated during 20 h. The results show that the reaction rate is high for the first 2 h, thus the value of solid waste and oxygen decrease quickly while value of produced gases increases. The mass increase of polychlorinated dibenzo-p-dioxins/furans and polybrominated dibenzo-p-dioxins/furans during the whole time of the process is linear with mild slope but for the other compounds, including steam, carbon dioxide, nitrogen, nitrogen oxide, sulphur dioxide, hydrogen chloride and hydrogen bromine, the slope of variations becomes mild after 3 h. The process becomes steady state almost after 9 h

Impact of high plasma concentrations of dioxin and polychlorinated biphenyls [PCBS] in south Indian women with endometriosis

To estimate the levels of Dioxin and PCBs present in the plasma of women with different stages of endometriosis and relation between Dioxin, PCBs and their possible impact on the pathogenesis of endometriosis. A prospective case control study. Department of Reproductive Medicine, Bhagawan Mahavir Medical Research centre, Maternal Health and Research Trust, and Owaisi Hospital AND Research Center Hyderabad, Andhra Pradesh, India. 97 women with endometriosis undergoing laparoscopy and 102 controls. Heparinised blood samples were collected for dioxins, PCBs estimation. The levels of dioxins and PCBs were measured via gas chromatography. Women with endometriosis showed significantly higher concentrations of dioxin and PCBs when compared with the control group. The correlation between the concentrations of dioxin -TCDD, PCBs, and difference in the severity of endometriosis was strong and statistically significant at p<0.05 for all the four compounds PCB-1: r=+0.53; P<0.0001, PCB-5: r=+0.67; P<0.0001, PCB-29: r=+0.64; p<0.0001, PCB-98: r=+0.43; p<0.0014 and concentration of dioxin-TCDD: r=+0.36, p<0.0001. These results suggest that women having higher concentration of Dioxin and PCBs might have an increased susceptibility to endometriosis

O impacto dos fatores ambientais na fertilidade / The impact of environmental factors in fertility

A infertilidade afeta até 15 por cento da população sexualmente ativa e em 50 por cento dos casos o fator masculino está envolvido, como problema primário ou em combinação com causas de origem feminina. Como muitas drogas comumente encontradas e medicações podem ter efeitos deletérios na infertilidade masculina, a avaliação médica deve incluir uma discussão sobre o uso de drogas ilícitas, medicamentos e outras substâncias que podem prejudicar a fertilidade. Com oconhecimento de quais drogas e medicamentos podem ser prejudiciais a fertilidade, talvez seja possível mudar os habitos ou a posologia das medicações para diminuir os efeitos adversos na fertilidade e aumentar as chances de engravidar com sucesso.

Infertility affects up to 15 per cent of the sexual active population and in 50 per cento of cases, a male factor is involved either as a primary problem on in combination with a problem in the female partner. Because many commonly encountered drugs and medications can have a detrimental effect on male fertility, the medical evaluation should include a discussion regarding the use of illicit drugs, medications, and other substances that may impair fertility. With the knowledge of which drugs and medications may be detrimental to fertility, it may be possible to modify a patient's habits or medications regimen to decrease adverse effects on fertility and improve the chances of achieving a successful pregnancy.

Compuestos disruptores endocrinos y su participación en la programación del eje reproductivo / Endocrine disruptor compounds and their role on the developmental programming of the reproductive axis

Different perturbations during fetal and post natal development unleash endocrine adaptations that permanently alter metabolism, increasing the susceptibility to develop later disease, process known as "developmental programming"'. Endocrine disruptor compounds (EDC) are widely spread on the environment and display estrogenic, anti-estrogenic or anti-androgenic activity; they are lypophilyc and stored for long periods on the adipose tissue. Maternal exposure to EDC during pregnancy and lactation produces the exposure of the fetus and neonate through placenta and breast milk. Epidemiological and experimental studies have demonstrated reproductive alterations as a consequence of intrauterine and/or neonatal exposure to EDC. Diethystilbestrol (DES) is the best documented compound, this synthetic estrogen was administered to pregnant women at the BO and 60 to prevent miscarriage. It was implicated in urogenital abnormalities in children exposed in utero and withdrawn from the market. The "DES daughters" are women with high incidence of vaginal hypoplasia, spontaneous abortion, premature delivery, uterine malformation, menstrual abnormalities and low fertility. The "DES sons" show testicular dysgenesis syndrome, which is characterized by hypospadias, cryptorchidism and low semen quality. This entity is also associated to the fetal exposure to anti-androgens as flutamide. The effects on the reproductive axis depend on the stage of development and the window of exposure, as well as the dose and the compound. The wide distribution of EDC into the environment affects both human health and ecosystems in general, the study of their mechanisms of action is extremely important currently.

Diversas perturbaciones durante el desarrollo fetal y posnatal desencadenan adaptaciones endocrinas que modifican permanentemente el metabolismo, incrementando la susceptibilidad para el desarrollo de enfermedades, proceso conocido como "programación durante el desarrollo". Los compuestos disruptores endocrinos (CDE) se encuentran en el medio ambiente y presentan actividad estrogénica, antiestrogénica o antiandrogénica; son altamente lipofílicos y se almacenan por periodos prolongados en el tejido adiposo. La exposición materna a CDE durante el embarazo y la lactancia permite su paso al producto a través de la placenta y la leche materna. Estudios epidemiológicos y experimentales han demostrado alteraciones en el eje reproductivo como consecuencia de la exposición intrauterina y/o neonatal a CDE. El compuesto mejor documentado es el dietilestilbestrol (DES), este estrógeno sintético fue administrado a mujeres embarazadas durante los 50s y 60s y retirado del mercado por su implicación en anormalidades urogenitales de los bebés expuestos in útero. Las denominadas "hijas del DES" son mujeres con alta incidencia de hipoplasia vaginal, malformaciones uterinas, irregularidades menstruales, baja fertilidad y alta prevalencia de aborto espontáneo y parto prematuro. Por su parte, "los hijos del DES" presentan una entidad clínica conocida como síndrome de disgenesia testicular caracterizado por hipospadias, criptorquidia y baja calidad del semen. Este síndrome también se asocia a la exposición fetal a compuestos antiandrogénicos como la ñutamida. Los efectos en el eje reproductivo dependen del estadio de desarrollo y del tiempo de exposición, así como de la dosis y el compuesto del que se trate. La extensa presencia de CDE en el ambiente afecta la salud humana e impacta al ecosistema en general por lo cual es de suma importancia el estudio de los mecanismos involucrados en su acción.