Abstract
The high prevalence of goiter in Saharan children visiting Asturias in the summer prompted us to study the problem in greater depth.
Neck palpation was performed in a sample of 570 school children from the Saharawi Arab Democratic Republic. Weight, height, T4, thyroid-stimulating hormone and anti-thyroperoxidase antibodies in capillary blood were determined. Urine samples were taken to measure iodine, fluoride and thiocyanate content. These substances were also determined in drinking water.
Goiter was found in 58.1% of the children (7% grade 2). Prevalence was greater in girls (65.4 vs 51.4%). The mean urinary excretion of iodine was 965 ± 348 µg/l, with no differences in gender or degree of goiter. In all children thyroid function was normal and autoimmunity was negative. Thiocyanate levels were normal. Iodine concentration in drinking water was 180-400 µg/l, with high fluoride content (0.7-1.5 mg/l).
In summary, we describe a geographical area with a high prevalence of goiter (58%) among school children and high urinary iodine levels (965 ± 348 µg/l). The main source of these highly elevated quantities was drinking water (between 180 and 400 µg/l). Thyroid function was normal. Autoimmunity was ruled out as the etiology of this endemic goiter and antithyroid compounds were not found in water or in the children’s urine.
We believe that the high prevalence of goiter in this population could be due to many factors such as excess iodine and fluoride, the hardness of the drinking water, and possibly to occasional water contamination.