EPIDEMIOLOGY OF ENDEMIC GOITER IN WESTERN COLOMBIA

  • 1 January 1978
    • journal article
    • research article
    • Vol. 56  (3) , 403-416
Abstract
Recent epidemilogical observations in western Colombia are reported which further demonstrate the presence of naturally-occurring goietrogens contaminating water supplies in areas where goiter persists despite prolonged and continuous I supplementation. Prospective and cross-sectional studies in 41 localities where the populations were on a uniform and adequate I supplementation for the last 10-20 yr indicate that, in the endemia of western Colombia, environmental factors other than nutritional I deficiency are responsible for differences in goiter prevalence. Further epidemiological studies to determine the causal factors for the persistnece of the endemia established a correlation between the sources of drinking water and goiter prevalence rates. Organic compounds containing S with marked thionamide-like antithyroid activity were isolated from water supplying endemic goiter districts, and results are presented indicating that sedimentary rocks rich in organic matter are the main source of water-borne goiterogens. Bacteriological investigations showed that the presence of Klebsiella pneumoniae in drinking water and bacterial concentration were related significantly with goiter prevalence only in the presence of other variables, particularly the presence of sedimentary rocks. At present, endemic goiter in western Colombia is not due to nutritional I deficiency. Rather, water supplies are contaminated with S-bearing organic compounds with thionamide-like antithyroid activity, most probably deriving from sedimentary rocks rich in organic matter, and these compounds are the main factor underlying the endemia.