UPTAKE PATHWAYS OF ORGANIC-CHEMICALS FROM SOILS BY AGRICULTURAL PLANTS

The uptake of eight organic xenobiotics from soil by plants was studie d in a closed aerated laboratory soil-plant system which allowed to di stinguish between uptake via the roots and via the leaves after evapor ation. Residues of all chemicals tested were detected in roots and in shoots; however, uptake pathways were different. For hexachlorobenzene (HCB) and octachlorodibenzo-p-dioxin(OCDD), no translocation from root s and vice-versa was observed. The s-triazine terbuthylazine was taken up nearly exclusively by the roots and translocated to the shoots. Th e herbicides chlorotoluron and trichloroacetic acid (TAC) were transpo rted in both directions. The uptake of trichloroethylene (TCE), chloro benzene and methyl-t-butylether (MTBE) was dominated by foliar uptake.