Fate of Malathion in an Activated Sludge Municipal Wastewater Treatment System.

摘要

Organophosphate compounds are used as pesticides and in chemical warfareagents such as nerve agents. VX ((O-ethyl S- 2-(diisopropylamino)ethyl) methylphosphonothioate) is one of the most toxic and environmentally persistent of these nerve agents. This research examined the fate of malathion, a pesticide and surrogate of VX O-ethyl S- 2-(diisopropylamino) (ethyl)(methylphosphonothioate), in bench-scale activated sludge (AS) sequencing batch reactors. Sorption kinetics and sorption equilibrium isotherm experiments indicate that sorption to AS biomass was not a statistically important removal mechanism. However, approximately 90% of the initial 4.25 mg L-1 malathion concentration degraded primarily via heterotrophic activity.