1998 Volume 35 Pages 119-128
Chromosomal aberration test was carried out to evaluate mutagenicity of organophosphoruspesticides during drinking water chlorination. Pesticides tested were fenitrothion (MEP), isofenphos, and diazinon which are P=S type;and dichlorvos (DDVP) which is P=O type.The respectiveoxygen analogs (P=O) were the major chlorination by-products of thiophosphorus (P=S) pesticides. It was found that the reaction with chlorine rather than hydrolysis was the main reason ofdecrease in oxygen analogs and DDVP in the actual drinking water supply process. Chromosomalaberration tests suggested that mutagenicity of MEP and isofenphos increase during chlorination. There was also the same variation tendency between the oxygen analog and activity inducing chromosomalaberrations of MEP after chlorination. MEP disappears by the reaction with chlorine, however, activity inducing aberrations of chlorinated water can be found. The large part of activity inducingaberrations of chlorinated MEP can be attributed to the oxygen analog. On the other hand, there wasnot a relationship between TOX and activity inducing aberrations of MEP. Weak activity inducingaberrations of diazinon was found just after chlorination and decreased gradually. Activity inducingaberrations of DDVP decreased with the decrease of DDVP itself and TOX.
