|Self-reported dermatitis and skin cancer in California farm operators
Susitaival, P., M.B. Schenker, R. Beckman and S.J. Samuels
In Preparation. 1999. .
Farming in different areas of the world varies with respect to crops, animals tended and chemicals used, but agricultural work is always associated with numerous skin irritants and allergens. Systematic registering of farmers' work-related diseases is done in few countries. In California, the highest rates of observed occupational skin diseases have been in farm workers (Mathias & Morrison 1988). Plants, agricultural chemicals (mainly pesticides), and food products have been the main causative agents of the occupational skin diseases (Mathias 1989, O'Malley & Mathias 1988). The actual causal role is not determined in the California statistics, and thus the role of specific agents, e.g. pesticides, may well be overemphasized (Edmiston & Maddy 1987). In the Finnish Register of Occupational Diseases, the main causes of farmers' occupational hand eczema have been cow dander, disinfectants and detergents, wet and dirty work, and rubber chemicals. The differences in the reporting of skin cancer by farm type, mainly the small figure (one case) in field farming, remain obscure in this study, and may be associated with underreporting. One explanation could be a possible role of specific chemicals used now or earlier in other than field farming. Specific chemicals can be hypothesized as being factors or cofactors in skin cancer development. Unfortunately, skin cancer is a disease that has a long latent period and often slow progression, and thus many years may pass after a possibly relevant exposure before the cancer is detected. For example, arsenic elevates the risk of skin cancer up to 60 years after the exposure. Arsenic-containing pesticides were used up to the 1970s, e.g. in wine growing, and they have also been known to contaminate ground waters (Peoples et aL 1979, Pershagen 1981). In order to get information on the hypothesized role of agrochemicals as skin cancer risk factors, more in-depth studies are needed.