Lewisite carcinogenic potential

The subcommittee believes the potential enviromnental and metabolic breakdown products of lewisite are not well identified. There is a possibihty that inorganic arsenic and perhaps even vinyl chloride, two known carcinogens, may be break down products. Accordingly, the subcommittee recommends that the environmental degradation and metabolic products of lewisite be determined, and, if those breakdown products are found to be produced, that the carcinogenic potential of those substances, as well as lewisite, be considered in future assessments. 

Data are inadequate to quantitatively assess the potential carcinogenicity of lewisite. There are inadequate human and inadequate animal data regarding the carcinogenic potential of lewisite. Genotoxicity data are equivocal or negative. 

It was recommended by the MCRA Working Group that for risk assessments, the carcinogenic potential of lewisite degradation products be considered. 

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