| Abstract
| - Solid-phase microextraction (SPME), a single-stepsolvent-free extraction, followed by gas−liquid chromatography (GC) employing a nitrogen−phosphorusdetector (NPD) and mass spectrometry (MS) wasevaluated for the measurement of the 46 nitrogen-and phosphorus-containing pesticides of U.S. EPAMethod 507. Effects of pH, ionic strength, methanolcontent, and temperature on extraction were determined.Analytes were extracted into a bonded polydimethylsiloxane phase coated on a fused-silica fiber andthen thermally desorbed in a GC injector andanalyzed. Absorption−time and absorption−concentration profiles were obtained for each SPME-extractable pesticide. When analyzed by SPME GC/NPD or by SPME GC/MS, 34 and 39 pesticides,respectively, were measured at levels lower than theEPA method detection limits and precision requirements. This method was applied to the analysis ofcontaminated well water, watershed, and streamwater and compared to U.S. EPA Method 507 findings.These results demonstrate that SPME is a valuabletool for the rapid screening of 39 EPA Method 507nitrogen- and phosphorus-containing pesticides in water.
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