EN
The influence of Cr (III) and Cr (VI) on biochemical reactions in the environment depends in part on the possibility of its getting from soil to soil solutions. The various methods of sequential extraction of Cr from soil were studied (Tessier et al. [1, 2], Rudd [3], BCR [4-7], Gatehouse [8], Kersten and Förstner [9], Psenner [10], Sposito [11]) in order to characterize chemical fractions. It was found that chromium determination depends on the method used and varies from 18.2% (BCR) to 96.5% (Tessier) of chromium detection in soil (34.1 mg·kg⁻¹). Quantitative evaluation of chemical fraction of Cr in soil by methods of sequential extraction was carried out by Tessier [1-2], Kersten and Förstner method [9] and indicated that Cr desorption increases according to the following order: exchangeable fraction