RESUMO
In the last decades it has been found out that elevated levels of nitrates in drinking water and eatable plants have the negative impact on human health. During transportation, keeping and preparing the vegetables for consumption, as well as in the human body itself, nitrates undergo the reduction into nitrites (nitrate(III)). This reduction process runs relatively fast in the alimentary canal of infants under the age of 6 months. Nitrites, in the presence of some substances that occur in foodstuff, can favour the cancerogenic processes. In addition to that, nitrites can lead among infants to the disease called methemoglobinemia (blue baby syndrome). In 1986 WHO fixed the limit of the contents of nitrates in drinking water to 10 mg N-NO3-/dm3 (45 mg NO3-/dm3). The aim of this study was to evaluate the level of nitrates in the water of selected drinking water wells situated in the parish of Szydlowiec, a province of Swietokrzyskie. The study was conducted in three series, i.e.: in the summer of 1995, in the winter of 1996 and in the summer of 2001. The concentration of NO3- in water was determined (in situ) with the Merckoquant Nitrate test kits of the Merck Company. The obtained results show that the NO3- concentration in the water of the majority of studied wells exceeds clearly the acceptable NO3- drinking water standard established for drinking water by WHO.
