title: Determination of organophosphorus pesticides in underground water by SPE-GC-MS.
abstract: A rapid and effective method is developed for the determination of organophosphorus pesticides (dichlorovos, methyl parathion, malathion, and parathion) in underground water by solid-phase extraction (SPE)-gas chromatography-mass spectrometry. Some important extraction parameters including types of SPE adsorbents, elution solvents, and injection volume of water samples are optimized. The use of Cleanert-PEP polymer SPE column improved higher extraction efficiencies than the C18 SPE column commonly used. Water samples are extracted using Cleanert-PEP as SPE adsorbent and ethyl acetate as elution solvent. Precision values expressed as relative standard deviation for 1 microg/L of spiked water sample are in the range of 1.6-4.0%. Dichlorvos, methyl parathion, malathion, and parathion are linear in the range of 0.1-1.0 microg/L (r2=0.9976), 0.1-2.0 microg/L (r2=0.9883), 0.1-2.0 microg/L (r2=0.9798), and 0.055-1.1 microg/L (r2=0.9790), respectively. The limits of detection for spiked water samples are in the range of 4-10 ng/L. The optimized method is applied to the determination of underground water samples. Recoveries are between 59.5% and 94.6% for spiked underground water samples. The benefit of the method developed is rapid, simple, and has good repeatability.
authors.affiliation: Key Lab of Environmental Engineering in Shandong Province, Institute of Environment & Municipal Engineering, Qingdao Technological University, Qingdao 266033, P.R. Ronghui China. majiping2001@yahoo.com.cn
authors.forename: Jiping
authors.initials: J
authors.lastname: Ma
authors.forename: Ronghui
authors.initials: R
authors.lastname: Xiao
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.forename: Xiuhua
authors.initials: X
authors.lastname: Zhao
authors.forename: Benzhang
authors.initials: B
authors.lastname: Shi
authors.forename: Shuqing
authors.initials: S
authors.lastname: Li
mesh_terms: D004006:Dichlorvos / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D007306:Insecticides / Q000032:analysis; D008294:Malathion / Q000032:analysis; D008743:Methyl Parathion / Q000032:analysis; D009943:Organophosphorus Compounds / Q000032:analysis*; D010278:Parathion / Q000032:analysis*; D052616:Solid Phase Extraction; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D007306:Insecticides; D009943:Organophosphorus Compounds; D014874:Water Pollutants, Chemical; D008743:Methyl Parathion; D010278:Parathion; D004006:Dichlorvos; D008294:Malathion