Polychlorinated biphenyls mammals

Kannan, N., S. Tanabe, M. Ono, and R. Tatsukawa. 1989. Critical evaluation of polychlorinated biphenyl toxicity in terrestrial and marine mammals increasing impact of non-ortho and mono-ortho coplanar polychlorinated biphenyls from land to ocean. Arch. Environ. Contam. Toxicol. 18 850-857. 

Kuehl, D.W., B.C. Butterworth, J. Libal, and P. Marquis. 1991. An isotope dilution high resolution gas chromatographic-high resolution mass spectrometric method for the determination of coplanar polychlorinated biphenyls application to fish and marine mammals. Chemosphere 22 849-858. 

DL Hayteas, DA Duffield. Use of high-performance liquid chromatography for the estimation of polychlorinated biphenyls and p,p -DDE residues in marine mammals. J Chromatogr B 705 362-366, 1998. 

It is very likely that the polybrominated biphenyls are metabohzed in fish, sea mammals, and human to debrominated and hydroxylated polybrominated biphenyls. It is suggested by the authors that some of these polybrominated metabolites can bind to the estrogen receptor and act hke xenoestrogens, as was shown for hydroxy polychlorinated biphenyls (HO-PCBs) by Korach et al. [256], McKinney and Waller [257], and Waller et al. [258]. Especially the chemical structure of para-substituted hydroxylated metabohtes of polybrominated biphenyls would be similar to that of estradiol, preferably in the presence of... 

Bioaccumulation results when uptake of chemicals by dietary and nondietary pathways exceeds metabolism and excretion. Rates at which substances are absorbed, altered, and then excreted are relatively important. Bioaccumulation may involve sequestration mechanisms, such as the deposition of polychlorinated biphenyls (PCBs) in fat, or the incorporation of lead in the mineral portion of bone. Incorporation into fat is dependent on the lipophilicity of the compound. The most commonly performed test of lipophilicity involves experimental determination of the equilibrium partitioning of a test compound between octanol, a nonmiscible organic solvent, and water, often expressed as the log10 of the ratio or the octanol/ water partition coefficient (log K ). Organic compounds in which the log Kow value is less than 3.5 do not appreciably accumulate in the lipids of mammals [5], Because energetic compounds have relatively low log Kow values (Table 10.1), bioaccumulation cannot be explained solely by lipophilicity. 

Polychlorinated biphenyls (PCBs) and dioxins are two groups of toxic organic contaminants that are widespread throughout the ecosystem as a consequence of its persistence and potential for bioaccumulation in the environment. These occur in water, air, soil, sediment, and biota in different areas around the world. In general, water birds and marine mammals have accumulated the dioxins and dioxin-Uke PCBs with much higher concentrations than humans, implying higher risk from exposure to wildlife. ... 

Wong et al. [33] studied the enantiomeric composition of polychlorinated biphenyl (PCB) enantiomers in rivers from selected sites throughout the United States. Nonracemic enantiomeric fractions (EFs) were observed for PCBs 91, 95, 136 and 149 in aquatic samples. Bromocyclen, a new insecticide with a low toxicity to mammals, is currently in use in Europe for the treatment of domestic animals against ectoparasites. Therefore, bromocyclen has been reported in the waters of the Stor river, a tributary of the River Elbe in northern Germany [34-36]. Franke et al. [37] reported chlorinated bis(propyl)ethers in the waters of the River Elbe. Three isomers of bis(propyl)ethers have been reported in different parts of the river, and the authors identified an epichlorohydrin production site, close to the Czech border, as the source of this contamination. Many toxic pesticides, such as BHC, aldrin, dieldrin, DDT and so on, have been detected in the Yamuna River, which is a very important river in India [38], Similarly, DDT, BHC, aldrin, dieldrin, malathion and so on have also been detected in another very famous river, the Ganges [39]. Recently, Ali and Jain [40] have reported the presence of lindane, malathion, BHC, p,p -DDD, o,p -DDT and methoxychlor in the Hindon River, also in India. 

Exposure to xenobiotics raises the risk of male infertility, breast cancer in females, feminization of male animals and the evolution of antibiotic resistant strains of bacteria. Of particular concern are endocrine disruptors such as polychlorinated biphenyls (PCBs), which are chemicals that at certain doses can interfere with the endocrine (or hormone) system in mammals. These disruptions can cause cancerous tumours, birth defects and other developmental disorders. 

Being at the end of the food chain, carnivorous marine mammals accumulate in their blubber chlorinated pesticides of anthropic origin, especially DDT, chlordanes, PCBs (polychlorinated biphenyls) and heptachlor, at concentrations that may be toxic to the animals. The lipid and chlorinated pesticide compositions are related to the diet the diet may be deduced, at least in part, from the detailed composition of the blubber. This approach to the biochemistry of marine mammals has produced a great number of publications, the most recent of which include the following Maruya and Lee (1998) Aguilar, Borrell, and Pastor (1999) Kannan et al. (2000) Ross et al. (2000) Watanabe et al. (2000) Kajiwara et al. (2001) Kubota, Kunito, andTanabe (2001) Le Boeuf et al. (2002) Hoekstra et al. (2003) Vetter, Jun, and Althoff (2003) Hansen et al. 

Kannan, K., Blankenship, A.L., Jones, P.D., and Giesy, J.P. (2000) Toxicity reference values for the toxic effects of polychlorinated biphenyls to aquatic mammals. Human Ecol. Risk Assess., 6,181—201. 

Although drugs such as acetaminophen bind to AhR, the majority of AhR agonists or antagonists are environmental chemicals. Polychlorinated diben-zodioxins such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), dibenzofu-rans, biphenyls, and a number of other chemicals are widespread pollutants in aquatic ecosystems. These compounds cause a high reproductive and developmental toxicity, which is mediated via binding to the AhR. Thus they pose a serious threat to many populations of mammals, birds, and fish. Various adverse effects—including structural malformations, reduced fertility, tumor promotion, immunotoxicity, and skin disorders like chloracne—have been observed [139]. 

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