Fate of chloroalkylene-9-¹⁴C in carrots, sugar beets, and soil under outdoor conditions

Abstract

Immediately after application of chloroalkylene-9-¹⁴C to soil (1.32 ppm, based on dry weight of soil in the upper layer of 0 to 10 cm) under outdoor conditions, carrots were sown; in the following year, sugar beets were grown. About 80% of the radioactivity applied volatilized within one vegetation period. Most of the remaining radioactivity was still in the upper soil layer; 0.8% had dispersed to a depth of 40 cm, and 3.3% was taken up by the carrot plants. In the second year, no more decrease of soil residues was observed; uptake by sugar beets was 0.1% of the applied radioactivity.

In the first year, the residues in the upper soil layer consisted of 41% unchanged chloroalkylene-9, 19% soluble metabolites, and 40% unextractable residues; the amount of unextractable residues rose to 68% in the second year. The following conversion products were characterized in the soil extracts: a monohydroxylated dichlorobiphenyl, a monomethoxylated dichlorobiphenyl, and two isomeric monohydroxylated, monoisopropylated dichlorobiphenyls; in carrot roots, a monomethoxylated dichlorobiphenyl was detected. Conjugates occurring in the soil yielded, after acid hydrolysis, a monohydroxylated dichlorobiphenyl among other compounds.