title: Isolation and concentration of organophosphorus pesticides from drinking water at the ng/L level, using macroreticular resin.
abstract: A screening method has been developed for determining organophosphorus pesticides at ng/L levels in drinking water. Sixteen organophosphorus pesticides, diazinon, diazinon-oxon, dimethoate, ronnel, beta-phosphamidon, methyl parathion, ethyl parathion, malathion, chlorpyrifos, fenitrothion, ruelene, methidathion, ethion, EPN, phosalone, and phosmet, were extracted by Amberlite XAD-2 resin from 100 and 200 L drinking water previously spiked with these pesticides. The pesticides were eluted from the XAD-2 resin with acetone-hexane (15+85). The concentrated extract was analyzed by gas chromatography using a nitrogen-phosphorus selective detector and by gas chromatography-mass spectrometry using selected ion monitoring. Recoveries at the 10 and 100 ng/L spiking levels were greater than 90%, except recoveries for dimethoate and phosphamidon were 37 and 42%, respectively. The analysis of 300 L Ottawa tap water showed no detectable amounts (less than 1 ng/L) of any of the 16 organophosphorus pesticides.
mesh_terms: D002849:Chromatography, Gas; D007306:Insecticides / Q000032:analysis* / Q000302:isolation & purification; D007475:Ion Exchange Resins; D013058:Mass Spectrometry; D008722:Methods; D008832:Microchemistry; D009943:Organophosphorus Compounds; D009946:Organothiophosphorus Compounds; D011137:Polystyrenes; D014881:Water Supply / Q000032:analysis*
chemical_list: D007306:Insecticides; D007475:Ion Exchange Resins; D009943:Organophosphorus Compounds; D009946:Organothiophosphorus Compounds; D011137:Polystyrenes; C003771:Amberlite XAD-2 resin