Radiation Exposure and Thyroid Disease in Kazakhstan

Residents of certain villages in Kazakhstan were exposed during childhood to radioactive fallout from nuclear tests conducted at the Semipalatinsk Nuclear Test Site (SNTS) between 1949 and 1962. Radiation doses to the thyroid from external and internal (i.e., ingested) radiation sources deposited as fallout are of interest because they may be jointly and differentially associated with increased risk of thyroid disease in this population. Objectives: To collect information about factors influencing radiation dose to the thyroid gland in children of two ethnic groups who were exposed to radioactive fallout from nuclear tests at the SNTS between 1949 and 1962. The two groups are Kazakhs (historically nomadic herders) and Europeans (typically descendants of Russian and German farmers). Eligibility: Women 70 years of age and older who had children or provided care to children during the 1950s. Men age 70 and older who were engaged in farming and care of dairy animals at the time of the nuclear tests. Design: In focus group format, participants are interviewed to collect information on the following at the time of nuclear tests: * Dairy consumption; * Source, storage and availability of milk and milk products; * Time that children of different ages and ethnic groups spent indoors; * Building material of houses and schools; * Herding, grazing and supplemental feed of dairy animals.