DEGRADATION OF ALDICARB, ALDICARB SULFOXIDE, AND ALDICARB SULFONE IN CHLORINATED WATER

The three insecticidal species of Temik, aldicarb (I), aldicarb sulfoxide (II), and aldicarb sulfone (III), degrade rapidly in chlorinated water. I is sulfoxidized to II, while II forms III, (chloromethyl)sulfonyl species, and N-chloro-II. III forms N-chloro-III, which decomposes to III acid and dichloromethylamine. Over the pH range of 6-9, the degradation rates of I-III in chlorinated water are several orders of magnitude faster than base hydrolysis, the primary detoxification mechanism in water. Chlorination of aldicarb species during drinking water treatment can reduce the initial concentrations but may produce compounds of concern to public health.