Monitoring of herbicides in river water by gas chromatography- mass spectrometry and solid-phase extraction

摘要

A gas chromatography-mass spectrometric method was developed to determine concentrations of herbicides in both the dissolved phases and the suspended phase of river water. The target herbicides were 2-amino-3-chloro-l,4-naphthoquinone, alachlor, benfluralin, bifenox, bromobutide, the debromo form of bromobutide, butachlor, butamifos, ehlomethoxyfen, chlornitrofen, chlorpropham. dimepiperate, dimethametryn. dithiopyr, esprocarb, MCPA-ethyl, MCPA-thioethyl, mefenacet, molinate, naproanilide, oxadiazon,pendimethalin, piperophos, pretilachlor, prometryn, simazine. simetryn, thiobencarb and trifluralin. The herbicides in filtered river water were extracted with styrene-divinylbenzene copolymer and were eluted with acetone. The herbicides on suspended substances were extracted ultrasonic-ally with acetone. Recoveries of the herbicides on the overall performance of this method were 81.6% to 128% from filtered river water and 80.0% to 110% from suspended substances. The minimum detectable concentrations in water and suspended substances ranged from 0.01 mug 1~(-1) to 0.02 mug 1~(-1) and 0.05 mug g~(-1) to 0.1 mug g~(-1), respectively. This method was successfully applied to monitoring herbicides in river water.