Polychlorinated dibenzofurans human exposure

Ma J, Kannan K, Cheng J, Horii Y, Wu Q, Wang W (2008) Concentrations, profiles, and estimated human exposures for polychlorinated dibenzo-p-dioxins and dibenzofurans from electronic waste recycling facilities and a chemical industrial complex in Eastern China. Environ Sci Technol 42(22) 8252-8259. doi 10.1021/es8017573... 

In this section we will consider the exposure pathways of POPs to human beings on the example of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans... 

Eschenroeder A, Jaeger RJ, Ospital JJ, et al. 1986. Health risk analysis of human exposures to soil amended with sewage sludge contaminated with polychlorinated dibenzodioxins and dibenzofurans. Vet Hum Toxicol 28 435-442. 

Jones KC, Bennett BG. 1989. Human exposure to environmental polychlorinated dibenzo-p-dioxins and dibenzofurans An exposure commitment assessment for 2,3,7,8-TCDD. Sci Total Environ 78 99-116. 

Rappe C, Nygren M, Marklund S, et al. 1985. Assessment of human exposure to polychlorinated dibenzofurans and dioxins. Environ Health Perspect 60 303-304. 

Another major exposure route for humans is via contaminated food. For example, North America s Great Lakes, which are the largest body of freshwater in the world, are polluted with about 362 contaminants that were found in quantifiable amounts in the water, sediment, and biota (IJC 1983 USEPA 1994). The critical pollutants were identified as PCBs, DDT, dieldrin, toxaphene, mirex, methyl mercury, benzofa) pyrene, hexachlorobenzene, polychlorinated dibenzodioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and alkylated lead. Some of these pollutants biomagnify in the aquatic food chain and can be detected in increased levels in cooked Great Lakes fish. Consequently, the blood serum levels of these chemicals are significantly increased in consumers of contaminated Great Lakes sport fish compared to people who do not eat such fish (Flumphrey 1983 Fiore et al. 1989 Sonzogni et al. 1991). 

Fly ash from municipal waste and industrial waste incinerators contains polychlorinated dibenzo-p-dioxins (PCDDs), including tetrachlorodibenzo-/j-dioxin (TCDD) and polychlorinated dibenzofurans (PCDFs), which are lipophiles, and heavy metals, including chromium, copper, manganese, vanadium, and lead, which are hydrophilesJ29-31 These chemicals have multiple toxicities and are known to impact the human liver, immune system, respiratory system, thyroid, male reproductive function, and CNS J32 34l Several are human carcinogensJ32 35 Enhanced toxic effects are observed in the mixtures of some of theseJ21,22 36 The mixtures of toxicants present in fly ash are complex and the mechanisms for their action on the human body are largely unknown. It is known that occupational exposure to fly... 

Lucier GW, Nelson KG, Everson RB, et al. 1987. Placental markers of human exposure to polychlorinated biphenyls and polychlorinated dibenzofurans. Environ Health Perspect 76 79-87. 

Human Health Aspects of Environmental Exposure to Polychlorinated Dibenzo-p-dioxins and Polychlorinated Dibenzofurans. Universities Associated for Research and Education in Pathology, Inc., Bethesda, MD, 1988. 

Polychlorinated dibenzo-y>-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) are chemically classified as halogen-ated (polychlorinated) aromatic hydrocarbons (PHAH). Dioxins are formed as a by-product of chemical processes, whereas PCBs are synthesized by direct chlorination of biphenyls. Due to their lipophilic character, they are concentrated in the food chain and both humans and wildhfe are exposed to them. The major source of human exposure is through the diet, as these substances are concentrated in fatty tissues of beef, poultry, pork and fish, and through cigarette smoking. Moreover, maternal milk contains considerable amounts of PCBs and dioxins. 

Bocio, A., Domingo, J.L., 2005. Daily intake of polychlorinated dibenzo-p-dioxins/poly-chlorinated dibenzofurans (PCDD/PCDFs) in foodstuffs consumed in Tarragona, Spain A review of recent studies (2001-2003) on human PCDD/PCDF exposure through the diet. Environ. Res. 97, 1-9. 

Rappe C, Nygren M, Buser H, et al. 1983. Identification of polychlorinated dioxins (PCDDs) and dibenzofurans (PCDFs) in human samples, occupational exposure and Yusho patients. Environ Sci Res 26 241-253. 

Schecter A, Constable JD, Bangert JV, et al. 1989b. Isomer specific measurement of polychlorinated dibenzodioxin and dibenzofuran isomers in human blood from American Vietnam veterans two decades after exposure to Agent Orange. Chemosphere 18 531-538. 

Schecter A, Ryan JJ. 1988. Polychlorinated dibenzo-p-dioxin and dibenzofuran levels in human adipose tissues from workers 32 years after occupational exposure to 2,3,7,8-TCDD. Chemosphere 17 915-920. 

Schecter AJ, Schaffner F, Tieman TO, et al. 1985b. Biological markers after exposure to polychlorinated dibenzo-p-dioxins, dibenzofurans, biphenyls, and related chemicals. Part II Ultrastructural characterization of human Uver biopsies. In Keith L, Rappe C, Choudhry G, eds.. Chlorinated dioxins and dibenzofurans in the total environment, II. Boston, MA Butterworth Publishers, 247-264. 

Dioxins are a family of the most toxic chlorinated organic compounds known to science, numbering around 75 dioxins and 135 related furans. These can cause cancer and are ECD for humans, even at very low exposure levels, since minute amounts, can bio-accumulate due to their ease of solubility in body fat (dioxins are hydrophobic, water-hating and lipophilic, fat-loving ). Number and position of chlorine atoms in the molecule has a considerable effect on toxicity, and 17 dioxins are classed as highly toxic. These include polychlorinated dioxins (PCDD) and dibenzofurans (PCDF) which are by-products of the chlorine bleaching of paper, the burning of chlorinated hydrocarbons (such as pentachlorophenol, PCB, and PVC) and the incineration of municipal/medical... 

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