The fate of hydroxyatrazine in a soil and a lake sediment

Abstract

Ring 14C labelled hydroxyatrazine was incubated at room temperature with electron beam irradiated soil under aerobic and anaerobic conditions and in the presence or absence of a non-irradiated soil inoculum. Similar incubation experiments were conducted on a nonirradiated suspension of a lake sediment. A soil incubation at 99°C was also included. Evolution of 14CO 2 indicated that ring cleavage occurred at room temperature for all treatments except that of the uninoculated soil under anaerobic conditions. After 8–12 weeks, the residual hydroxyatrazine and degradation products were extracted with a series of solvents. The extracts were shown chromatographically to contain 14C labelled components other than hydroxyatrazine. No basic compounds were found and it is believed that a portion of the derivatives were compounds which had undergone modification of the ring substituents. Both aerobic and anaerobic species of microorganisms appear to be capable of metabolizing the hydroxyatrazine ring and non-biological chemical processes play no part in these transformations. Circumstantial evidence indicated that little or no chemical incorporation occurred between hydroxyatrazine or its derivatives and indigenous soil organic components.