[A study of victims of methylmercury poisoning outbreaks by age and sex in Minamata, Niigata and Iraqi outbreaks].

: To investigate features of the incidence of methylmercury poisoning cases presumably caused by intake of polluted foods in Japan and Iraq, several populations exposed to polluted foods were analyzed by geography and/or occupation. Ratios of confirmed cases to the corresponding number by age and sex in the defined exposed population were calculated. The distribution of the ratios showed a unimodal age distribution for both males and females in the Japanese Minamata and Niigata population. On the contrary, in the Iraqi population, ratios distributed equally by age and sex groups, having no peaks. This difference between the two countries is probably due to the difference of ingestion by age and sex in fish and wheat, which was the primary source of methylmercury exposure.