Pesticide transformations: production of chloroazobenzenes from chloroanilines.

Aniline and 11 different chloroanilines were added to soil. No azo compound was formed from aniline, but all monochloro-and some dichloroanilines were transformed to their corresponding dichloro-and tetrachloroazobenzenes. Other dichloroanilines and the trichloroanilines were stable in soil. Peroxidase catalyzed the formation of azo compounds by some chloroanilines. Correspondence in the range of substrates used and products formed in the two systems suggests a peroxidatic mechanism for the synthesis of azo compounds residues in soil.