ABSTRACT
By using whole blood selenium, 24 hr urinary selenium and hair selenium contents as the indices of assessing human selenium status, it was found that the populations in the endemic areas of Keshan disease were practically in a selenium poor status. The selenium contents in locally grown staple grains and daily diets in the endemic areas were also lower than those in the non-endemic areas. In an area covering a cross section of Keshan disease geographic belt in our country, the hair selenium contents of agricultural populations were measured. The results indicated that all the hair selenium contents in the endemic sites were always at a lower level, whereas those in the non-endemic sites distant from the endemic areas were generally at a higher level; they decreased gradually until the endemic areas were reached; and finally, along the contiguous region of the endemic and non-endemic areas they were insignificantly different.The hair selenium contents among the agricultural populations were significantly lower than those among the non-agricultural ones in the same endemic areas. However, no regular correlation had been observed between the seasonal prevalence of Keshan disease and the variation of hair selenium contents in the same populations living in the same endemic sites.It is considered that the endemic areas of the disease seem to be a Se-deficiency belt, and Se-deficiency probably might be a pathogenic geo-gen in the prevalence of Keshan disease.