Genotoxicity of organometallic species
The modification of metals and metalloids by formation of volatile metal hydrides and alkylated species (volatile and non-volatile) has a major impact on the processing of these elements in the environment. In general, the formation of such species increa
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Human exposure to organometallic species The modification ofmetals and metalloids by formation ofvolatile metal hydrides and alkylated species (volatile and non-volatile) has a major impact on the processing ofthese elements in the environment. In general, the formation of such speeies increases the mobility of the respective element and can result in its accumulation in biological systems (Craig and Glockling 1988). Many studies have shown that the production of organometal(loid) species is possible and likely whenever metal(loid)s in the presence of methyl donors are exposed to specific microorganisms under anaerobic conditions, at least on a microscale basis (Brinckman and Bellama 1978). These conditions may exist both in natural environments (e.g. wetlands, pond sediments) and in anthropogenie systems (e.g. waste disposal sites and sewage treatment plants). Other sources of organometal(loid)s are industrially produced compounds such as bioeides and catalysts. Organometal(loid)s can be released in the gaseous state or as aerosols into the atmosphere; via the solved state, they can enter the hydrosphere and soil. There is a steady exchange of these compounds between the compartments of the ecosphere. In the course of these exchanges, organometal(loid)s are taken up by humans, distributed in tissues, and eliminated via breath, urine, or faeces. For example, a variety of organometallic compounds with elements such as germanium, arsenic, selenium, tin, antimony, and mercury have been detected in human urine following consumption of seafood (Kresimon et al. 2001). The occurrence of organometal(loid)s in human tissues mayaiso result from bacterial activities in the intestinal tract (Kresimon et al. 2001).
A. V. Hirner et al. (eds.), Organic Metal and Metalloid Species in the Environment © Springer-Verlag Berlin Heidelberg 2004
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Florea et al.
Genotoxicity of organometallic species The potential of organometallic compounds for adversely affecting human health is well documented. This applies in particular to the neurotoxic and teratogenic effects of organomercurials. Examples are the poisoning ofthe Minamata Bay population with methylmercury (MeHg) (Harada 1978), the lethai epidemic in the Iraq where people ingested MeHg-contaminated com-products (Bakir et al. 1973), or, more recently, the death ofthe American chemist Karen E. Wetterhahn following accidental dermal exposure to dimethylmercury (Me2Hg) (Nierenberg et al. 1998). There are only few data published on genotoxic and carcinogenic effects of organometal(loid) compounds and on the mechanisms of their action at the cellular level. Increased interest in these topics came from the recent finding that methylated trivalent metabolites might contribute to the carcinogenicity of arsenic (StybIo et al. 2002). In the following chapters, studies on the genotoxic activity of organomercurials, organoarsenic compounds, and organotin compounds are briefly reviewed. Genotoxic effects of organomercury compounds
In a Brazilian population exposed to MeHg in drinking water
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