AbstractThe nitrate and nitrite levels were determined in two carrot varieties, cultivated in three Experimental Stations of Varieties Assessment in different regions of Poland in 1987–1989. The results obtained were analysed against soil conditions (kind and composition, richness), agrotechnical background (length of vegetation period, harvest time) and climatic conditions (air temperature and precipitation). The nitrate level in carrot was estimated at av. 349 mg KNO3/kg. Significant differences were found in nitrate levels depending on place and year of cultivation. The most significant effects of the studied factors on the nitrate level had soil richness in potassium and magnesium as well as length of vegetation period. The studied carrot displayed a high level of nitrites (av. 3.1 mg NaNO2/kg), which might have resulted from a microbiological reduction of nitrates occurring between harvest and the time of performing analyse