Vinyl chloride xenobiotic compound

Another form of chemical interaction, resulting from inhibition in vivo, that can then be demonstrated in vitro involves those xenobiotics that function by causing destruction of the enzyme in question, so-called suicide substrates. Exposure of rats to vinyl chloride results in a loss of cytochrome P450 and a corresponding reduction in the capacity of microsomes subsequently isolated to metabolize foreign compounds. Allyl isopropy-lacetamide and other allyl compounds have long been known to have a similar effect. 

Although vinyl chloride is carcinogenic in man, specific mycobacteria have been isolated, that are capable of aerobic growth on vinyl diloride as a sole source of carbon and energy. The reason, why these mycobacteria have (developed) the capacity to degrade this truly xenobiotic compound, remains unknown. 

Exposure to vinyl chloride is known to cause a specific kind of liver cancer in humans. After doing some Internet research on the subject, explain the statenentthat vinyl chloride is a xenobiotic compound and a protoxicant. 

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