Determination of Chemical Warfare Agents in Natural Water Samples by Solid-Phase Microextraction

Abstract

A novel analytical technique was developed for detection of nerve agents in natural water samples at ppb and sub-ppb (v/v) levels with GC-SIM and GC-NPD. Four different types of fibers for solid-phase microextraction (SPME) were evaluated, and a method was optimized with respect to sampling time and conditions. It was found that the 65 μm copoly(dimethylsiloxane/divinylbenzene) fiber was the best choice for extraction of the nerve agents. The precision, linear range, and detection limit were investigated for this fiber. Tap water, river water, seawater, and sewage water were spiked with 60 ppb (v/v) of nerve agents, and the samples were monitored for 1 week. This investigation shows that the SPME method is comparable to liquid−liquid extraction and has considerable potential for on-site inspections under the Chemical Weapons Convention.