Contribution of Fish to the Arsenic Exposure in Taiwan. K. J. Irgolic and W. Goessler; Institute for Analytical Chemistry, Karl-Franzens Universitaet Graz, Universitatsplatz 1, A-8010 Graz, Austria
For epidemiological studies in Southwest Taiwan that linked skin cancer, internal cancers, and blackfood disease with exposure to arsenic, the arsenic doses were calculated from total arsenic concentrations in water with neglect of contributions from food items. Such neglect in terms of total arsenic will cause regulatory limits (MCL, MAK, ...) to be set at values lower than necessary for adequate protection of public health. Because not all arsenic compounds are equally effective in leading to certain disease endpoints, exposures and doses must be established in terms of arsenic compounds (inorganic compounds: arsenite, arsenate; organic compounds: methylarsonic acid, dimethylarsinic acid, arsenobetaine, arsenic-containing riboses, arsenolipids). Inclusion of an arsenic compound that does not contribute to an endpoint in the total dose will produce regulatory limits higher than required. To arrive at regulatory limits that assure good public health but prevent unnecessary expenditures, arsenic compounds must be quantified in all items that contribute to the exposure of humans to arsenic. Because fish are a potentially rich source of arsenic that might overwhelm the contribution from drinking water, four species of fish that were consumed by the Taiwanese population in the arsenic-endemic area were investigated. The effect of the arsenic compounds found the fish on the total exposure and the dose-response curve will be discussed.