[Incidence of endemic goiter--environmental factors and iodine prophylaxis in Southern Poland].

In Southern Poland a well defined endemic goiter area has been known since 19th century. This region was characterized by low level of iodine in the environment. Iodine prophylaxis in Carpathian endemic area was introduced as early as 1935 at the level of 5 mg/kg of table salt. The goiter prophylaxis programme was interrupted during the Second World War. After the war in the years 1945-1946 epidemiological studies held in Southern Poland paid attention to high percentage of goiter in the population. As the result, potassium iodide salt supplementation started in 1947, but goiter incidence in subsequent years was still noted. As an effect of these observations, since 1956 potassium iodide salt supplementation was increased from 5 to 12 mg/kg of salt--in Carpathian and Subcarpathian regions. During over 30 years of iodide prophylaxis the severe symptoms of iodine deficiency disorders disappeared and endemic goiter in Southern Poland became mild. In 1980 the supplementation of kitchen salt was discontinued due to technical reasons. In 1985 an increase of goiter incidence in adults and children, as well as iodide deficiency disorders in newborns was noted. That is why in 1986 the salt supplementation was reintroduced at the level of 20 mg KJ/kg of kitchen salt. The potassium iodide content assessment in salt for human consumption in Krakow region was carried out in the years 1989-1994. The percentage of salt samples with the proper content of potassium iodide was 50, so it meant that the technological process of salt iodination was done incorrectly. Medical investigations are necessary to establish the optimal preventive dose of KJ.(ABSTRACT TRUNCATED AT 250 WORDS)