Formation of bound 14C-fonofos residues in an organic soil and a vegetable crop under field conditions

Abstract

The formation of bound (nonextractable) 14C residues in an organic soil treated with 14C-fonofos and in onions grown in the treated soil was investigated under field conditions. A steady decrease of extractable 14C residues was accompanied by a corresponding increase of bound 14C residues in the soil over the 130 day growing period. Fonofos was the major constituent present in the form of bound residues in soils. Onions harvested 130 days after treatment also contained small amounts of bound 14C residues in the form of fonofos oxon and trace amounts of methyl phenyl sulfone.