BACKGROUND: 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has a long half-life of 5-10 years in human beings as a result of its high lipophilicity, and little or no metabolism. We monitored TCDD, its form, distribution, and elimination in Victor Yushchenko after he presented with severe poisoning. METHODS: In late December, 2004, a patient presented with TCDD poisoning; the levels in his blood serum (108000 pg/g lipid weight) were more than 50 000-fold greater than those in the general population. We identified TCDD and its metabolites, and monitored their levels for 3 years using gas chromatography and high-resolution mass spectrometry in samples of blood serum, adipose tissue, faeces, skin, urine, and sweat, after they were extracted and cleaned with different organic solvents. FINDINGS: The amount of unmodified TCDD in the samples that were analysed accounted for about 60% of TCDD eliminated from the body during the same period. Two TCDD metabolites-2,3,7-trichloro-8-hydroxydibenzo-p-dioxin and 1,3,7,8-tetrachloro-2-hydroxydibenzo-p-dioxin-were identified in the faeces, blood serum, and urine. The faeces contained the highest concentration of TCDD metabolites, and were the main route of elimination. Altogether, the different routes of elimination of TCDD and its metabolites accounted for 98% of the loss of the toxin from the body. The half-life of TCDD in our patient was 15.4 months. INTERPRETATION: This case of poisoning with TCDD suggests that the design of methods for routine assessment of TCDD metabolites in human beings should be a main aim of TCDD research in the metabolomic era. FUNDING: University of Geneva Dermatology Fund, and Swiss Centre for Applied Human Toxicology.
Comment In: Lancet. 2009 Oct 3;374(9696):1131-219660808
The end products (digestate, solid fraction of the digestate, liquid fraction of the digestate) of ten biogas production lines in Finland were analyzed for ten hazardous organic compounds or compound groups: polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polychlorinated biphenyls (PCB(7)), polyaromatic hydrocarbons (PAH(16)), bis-(2-ethylhexyl) phthalate (DEHP), perfluorinated alkyl compounds (PFCs), linear alkylbenzene sulfonates (LASs), nonylphenols and nonylphenol ethoxylates (NP+NPEOs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA). Biogas plant feedstocks were divided into six groups: municipal sewage sludge, municipal biowaste, fat, food industry by-products, animal manure and others (consisting of milling by-products (husk) and raw former foodstuffs of animal origin from the retail trade). There was no clear connection between the origin of the feedstocks of a plant and the concentrations of hazardous organic compounds in the digestate. For PCDD/Fs and for DEHP, the median soil burden of the compound after a single addition of digestate was similar to the annual atmospheric deposition of the compound or compound group in Finland or other Nordic countries. For PFCs, the median soil burden was somewhat lower than the atmospheric deposition in Finland or Sweden. For NP+NPEOs, the soil burden was somewhat higher than the atmospheric deposition in Denmark. The median soil burden of PBDEs was 400 to 1000 times higher than the PBDE air deposition in Finland or in Sweden. With PBDEs, PFCs and HBCD, the impact of the use of end products should be a focus of further research. Highly persistent compounds, such as PBDE- and PFC-compounds may accumulate in agricultural soil after repeated use of organic fertilizers containing these compounds. For other compounds included in this study, agricultural use of biogas plant end products is unlikely to cause risk to food safety in Finland.
Persistent organic pollutants (POPs) are toxic compounds generated through various industrial activities and have adverse effects on human health. Studies performed in cell cultures and animals have revealed that POPs can alter immune-system functioning. The complement system is part of innate immune system that helps to clear pathogens from the body. We performed a large-scale population-based study to find out associations between summary measures of different POPs and different complement system markers.
In this cross-sectional study, 16 polychlorinated biphenyls (PCBs), 3 organochlorine (OC) pesticides, octachloro-p-dibenzodioxin, and 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) were analyzed for their association with levels of protein complement 3 (C3), 3a (C3a), 4 (C4) and C3a/C3 ratio. A total of 992 individuals (all aged 70 years, 50% females) were recruited from the Prospective Investigation of the Vasculature in Uppsala Seniors cohort. Regression analysis adjusting for a variety of confounders was performed to study the associations of different POP exposures (total toxic equivalency value or TEQ and sum of 16 PCBs) with protein complements.
The TEQ values were found to be positively associated with C3a (Ã?=0.07, 95% CI=0.017-0.131, p=0.01) and C3a/C3 ratio (Ã?=0.07, 95% CI=0.015-0.126, p=0.01) taking possible confounders into account. The association observed was mainly driven by PCB-126.
In this study involving 992 elderly individuals from the general population, we showed that POPs, mainly PCB-126, were associated with levels of complement system markers indicating that the association of these toxic compounds with downstream disease could be mediated by activation of immune system.
Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo, Norway; Pompeu Fabra University, Barcelona, Spain. Electronic address: firstname.lastname@example.org.
Maternal diet not only provides essential nutrients to the developing fetus but is also a source of prenatal exposure to environmental contaminants. We investigated the association between dietary intake of dioxins and PCBs during pregnancy and birth size. The study included 50,651 women from the Norwegian Mother and Child Cohort Study (MoBa). Dietary information was collected by FFQs and intake estimates were calculated by combining food consumption and food concentration of dioxins, dioxin-like PCBs and non-dioxin-like PCBs. We used multivariable regression models to estimate the association between dietary intake of dioxins and PCBs and fetal growth. The contribution of fish and seafood intake during pregnancy was 41% for dietary dioxins and dioxin-like PCBs and 49% for dietary non-dioxin-like PCBs. Further stratified analysis by quartiles of seafood intake during pregnancy was conducted. We found an inverse dose-response association between dietary intake of dioxins and PCBs and fetal growth after adjustment for confounders. Newborns of mothers in the upper quartile of dioxin and dioxin-like PCBs intake had 62g lower birth weight (95% CI: -73, -50), 0.26cm shorter birth length (95% CI: -0.31, -0.20) and 0.10cm shorter head circumference (95% CI: -0.14, -0.06) than newborns of mothers in the lowest quartile of intake. Similar negative associations for intake of dioxins and dioxin-like PCBs were found after excluding women with intakes above the tolerable weekly intake (TWI=14pg TEQ/kg bw/week). The negative association of dietary dioxins and PCBs with fetal growth was weaker as seafood intake was increasing. No association was found between dietary dioxin and PCB intake and the risk for small-for-gestational age neonate. In conclusion, dietary intakes of dioxins and PCBs during pregnancy were negatively associated with fetal growth, even at intakes below the TWI.
Exposure to chemicals via diet is a major uptake pathway for many compounds but is often estimated in a rather generic way. We use a new model framework (NMF) with crop-specific models to predict the dietary intake by 4-5-year-old children and 14-75-year-old women of three environmental compounds from their background concentrations in soil and air. Calculated daily intakes of benzo(a)pyrene and 2,3,7,8-TCDD are in good agreement with measured results from diet studies. The major source of both compounds in human diet is deposition from air. Inhalation of air and ingestion of soil play a minor role. Children take up more than twice the amount than adults per kg bodyweight, due to higher consumption per kg bodyweight. Contrary, the methods for indirect human exposure suggested in the Technical Guidance Document (TGD) for chemical risk assessment in the EU lead to overprediction, due to unrealistic consumption data and a false root model.