Abstract
An improved method for the determination of trace levels of pesticides in surface water has been developed and was used to analyze 20 target pesticides in New Jersey. Pesticides were extracted from 2 L water samples, using a mixture of XAD-2 and XAD-7 resins, and were determined by gas chromatography/chemical ionization mass spectrometry with ion trap detection. Average recoveries (performed in triplicate at the 1 ppb level, except for captan and chlorothalonil at 5 ppb) were between 75 and 113%, with an average coefficient of variation of 9%. Most of the pesticides (alachlor, atrazine, butylate, carbofuran, chlorpyrifos, diazinon, fonofos, isofenphos, metolachlor, metribuzin, parathion, and simazine) had limits of detection (LODs) of 0.005 ppb or lower, while some (carbaryl, cyanazine, fenamiphos, linuron, pendlmethalin, and terbufos) had LODs between 0.005 and 0.05 ppb. Captan and chlorothalonil had LODs of 1 ppb. Of 31 samples analyzed, 29 contained one or more of the following pesticides: alachlor, atrazine, carbaryl, chlorpyrifos, cyanazine, diazinon, isofenphos, linuron, metolachlor, and simazine in concentrations between trace (<0.025 ppb) and 5.48 ppb.
Simultaneous Determination of Various Pesticides in Rice by Ion-Trap Gas Chromatography/Mass Spectrometric (Chemical Ionization Method) Analysis
