Fate of [14C]aldrin in crop rotation under outdoor conditions.

[14C]Aldrin was applied to soils (about 3kg/ha) in outdoor boxes at various locations (Germany, England, and United States), and crops were cultivated (maize, wheat, sugar beets, and potatoes). In the following year, crop rotation experiments were carried out in the same soils without retreatment; in addition, wheat was grown in soils retreated with [14C]aldrin (3.5 kg/ha). After the harvest of both years, the distribution of aldrin and major metabolites (dieldrin; photodieldrin; hydrophilic metabolites including dihydrochlordene dicarboxylic acid; an unidentified nonpolar compound X; and unextractable metabolites) was determined in plants, soils, and leaching water. Two further conversion products, photoaldrin and aldrin-trans-diol, occurred in trace amounts only in a few samples. Metabolic pathways for aldrin under outdoor conditions are presented. The distribution of radioactive residues in soils and plants as well as their quantitative chemical composition are discussed, and comparisons are made between the different experimental sites, the crops, the first and second year, and retreated and nonretreated samples. The quantitative results are compared to those of field trials.