Environmental factors, cancers associated with

Multiple factors are associated with the development of colorectal cancer, including acquired and inherited genetic susceptibility, environmental elements, and lifestyle choices. Overall, about 37% of... 

Carcinogenic agents include chemicals in the environment, such as aniline and benzene, which are associated with the development of bladder cancer and leukemia, respectively. Environmental factors, such as excessive sun exposure, also may result in cancer. Viruses, including the human papilloma virus and hepatitis B, maybe associated with the development of cancer. Some of the chemotherapy agents cause secondary cancers after therapy has been completed. Numerous factors may contribute to the development of cancer. 

Ovarian cancer is associated with certain dietary and environmental factors as well. A diet that is high in galactose and animal fat and meat increases the risk of ovarian cancer, whereas a vegetable-rich diet is suggested to decrease risk.4,8 Although controversial, exogenous factors such as asbestos and talcum powder use on the perineal area also have been suggested to increase the risk of ovarian cancer.4,8... 

Many dietary and environmental factors have been implicated as possible etiologic factors in the development of pancreatic cancer, but no definite causal relationships have been established. The strongest evidence points to cigarette smoking as a risk factor associated with pancreatic cancer (20-24). Occupational exposure to certain chemicals has also been linked to pancreatic carcinoma (25). Others in the high-risk group include stone miners, cement workers, gardeners, textile workers, and leather tanners (17,26). 

Wicken, A.J., and S.F.Buck 1964. Report on a Study of Environmental Factors Associated with Lung Cancer and Bronchitis Mortality in Areas of North East England. Research Paper No. 8. Tobacco Research Council, London. 

Toxicity assessment includes characterization of the toxicity of a chemical, development of a dose-response relationship, and ultimately the development of exposure criteria. Toxicity values express a dose that is associated with either a given risk of cancer occurring over a lifetime of exposure (e.g., slope factors and unit risks) or a dose that is not expected to cause harm (e.g., RfDs). Some toxicity values are used as the basis for developing exposure criteria (RfDs) and some can be used as exposure criteria (e.g., RfCs). US EPA has developed toxicity values for many chemicals commonly associated with environmental contamination. Verified US EPA criteria are available in the Integrated Risk Information System (IRIS). 

Genetic make-up is certainly a factor that predisposes an individual to cancer - a familial pattern of breast cancer is, for example, well-established. However, an additive and even predominant environmental effect is clearly evident when one studies migrant populations. In Japan, the incidence of stomach cancer is high, probably due to a high consumption of salted fish and pickled foods but the incidence of prostate cancer is low, perhaps because this has an association with the consumption of large amounts of red meat. However, in migrant Japanese communities in the USA, the incidence of these two cancers more closely mirrors that of the native US population, suggesting that the adopted US diet has affected their predisposition to the two cancers. In addition, black Americans have similar incidences of the main cancers to white Americans, but these differ markedly from those seen in black Africans. 

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