Turnover rate and fate of radioactive parathion applied to an aquatic system

Investigates the assimilation and persistency of ¹⁴C‐parathion in an aqueous culture system. The radioactive pesticide was added to the nutrient medium of both soybean and wheat plants grown under aseptic and controlled conditions. Total applied radioactivity to the nutrient solution of both soybean and wheat were 1670 and 418 Bg, respectively. After 48 hours a balance sheet for the transported and recovered radioactivity was calculated. Turnover rate of the studied pesticide was concluded on the basis of its conversion to polar and non‐polar metabolites, in addition to the non‐extractable residues. Indicates that parathion has moderate persistence in the studied aqueous culture system; most of the applied radioactivity was transported from the nutrient solution and detected in the grown plants; polar metabolites were the predominant fraction in the nutrient solution as well as plant tissues; and in general, p‐nitrophenol was found in comparatively higher proportions as end product rather than paraoxon. Minor differences were evident regarding the metabolic behaviour of the pesticide under investigation in both soybean and wheat cultivating systems.