ABSTRACT
In the study it was intended to evaluate the concentration of nitrates and nitrites in some food products and samples of potable water collected in Kraków region and compile these results with frequency of recognised toxic methemoglobinemia cases. In the years 1991-1993 91 food samples, 288 samples of tap water from the central waterworks of Kraków and 399 samples of well-water from the country side of Kraków region were collected. In the chemical laboratories the nitrates and nitrites concentration has been defined. The clinical material of inpatients from 2 hospitals of Kraków and the data from the Poison Information Centre in Kraków have been analysed. The examined food samples did not present, in general, raised levels of nitrates and nitrites. Also the tap water samples presented a low concentration of these substances. The well-water samples demonstrated in considerable percentage increased levels of nitrates and nitrites and exceed the level permitted by sanitary law. In the Provincial Childrens Hospital during recent 14 years 8 infants with recognised methemoglobinemia were treated. All cases were connected with environmental pollution. At the Department of Toxicology, where only adults are treated, no methemoglobinemia cases resulting from environmental pollution during recent 26 years were hospitalized. The Poison Information Centre during recent 14 years consulted 239 cases of methemoglobinemia; 90% of them concerned children intoxicated because of environmental pollution.
