[Content of nitrates and nitrites in early vegetables and potatoes sold in the marketplace of Białystok in the year 1992].

Nitrate and nitrite were determined in early vegetables and potatoes sold in Białystok in 1992. The levels of nitrates and nitrites were determined in 248 samples. Nitrate and nitrite were evaluated spectrophotometrically by the method of the Griess reaction, after reduction of the nitrates to nitrites, with cadmium dust.