The Dissipation of Pyrimorph in Lake Water/Sediment Systems

Abstract

A study into the environmental behavior of pyrimorph in lake water/sediment systems has been carried out. The residue of pyrimorph in water and sediment for aerobic and anaerobic tests was determined, respectively. For aerobic test, the dissipation half-life of pyrimorph was 11.6 days in lake water of water/sediment system and 96.3 days in lake water of control treatment. For anaerobic test, the dissipation half-life of pyrimorph was 5.5 days in lake water of water/sediment system and 42.3 days in lake water of control treatment. Also, the pyrimorph concentration increased gradually in sediment of water-sediment system. The results showed that the dissipation of pyrimorph in water resulted mainly from sediment adsorption of pyrimorph and O2 inhibited the dissipation of pyrimorph. The degradation product of pyrimorph has been detected by HPLC-MS/MS. In the dissipation process, pyrimorph lost morpholine ring and formed an aldehyde compound.