Lungs arsenic-induced cancers

As Table 3.1 indicates, at least seven metals have been identified as human carcinogens, primarily of the lung. This may lead to the conclusion that these metals are extremely dangerous, and that any contact may result in cancer. On the contrary, based on available epidemiological evidence, it appears that the majority of metal-associated cancers are the result of chronic overexposure over a period of years or decades. With the exception of arsenic and lead, metal-induced cancers are largely preventable through the use of proper environmental controls or respiratory protective equipment. Surprisingly, two of the seven metals listed in Table 3.1, chromium and cobalt, are required in minute quantities as essential nutrients. Three others (arsenic, cadmium, and lead) may also be essential dietary nutrients. As Paracelsus indicated, it is not the substance that makes the poison, but the dose. 

Effects of long-term exposure to low levels of arsine are not well documented however, most of the reported deaths are believed to be secondary to acute renal failure. Exposure to other arsenic compounds to which arsine is metabolized can induce lung, bladder, kidney, and skin cancer in humans (Kleinfeld, 1980 Lenza, 2006). 

The potential for unusual health effects of chemical mixtures due to the interaction of chemicals or their metabolites (e.g., metabolites of trichloroethylene and benzene) in or with the biosystem constitutes a real issue in the public health arena. However, toxicity testing to predict effects on humans has traditionally studied one chemical at a time for various reasons convenient to handle, physiochemical properties readily defined, dosage could easily be controlled, biologic fate could easily be measured, and relevant data were often available from human occupational exposures. Chemicals are known to cause disease for example, arsenic and skin cancer, asbestos and lung cancer, lead and decrements of IQ, and hepatitis B predisposes to aflatoxin-induced liver cancer but the link between the extent of human exposure to even well-defined chemical mixtures and disease formation remains relatively unexplored, but of paramount importance to public health. 

Exposure to other arsenic compounds to which arsine is metabolized can induce lung, bladder, kidney, and skin cancer in humans (Fenza, 2006). 

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