Optimization of SPME for analysis of trichloroethylene in rat blood and tissues by SPME-GC/MS

Trichloroethyene (TCE) is a small halogenated compound that has been used extensively as a metal degreaser, dry cleaning agent, and all-purpose solvent. As a result of its widespread use, TCE is commonly found in the environment. TCE has limited water solubility; therefore, the compound is able to partition into drinking water. Human exposure to TCE in environmental media is of concern because TCE has been found to be carcinogenic in laboratory animals. The method presented in this paper uses solid phase microextraction coupled with gas chromatography and mass spectrometry (SPME-GC/MS) to analyze TCE in rat blood, plasma, liver, kidney, and lung. SPME pre-concentrates the sample, minimizes the use of extraction solvents, and minimizes sample preparation time. The limit of detection for this method is 1 ng/mL. For all biological specimens, placing the fiber in the sample headspace for 5 minutes for extraction of TCE gave maximal detector response. For blood and liver samples, heating samples prior to inserting the fiber improved the sensitivity. It is believed that sample heating overcomes TCE binding to heme-containing proteins in these matrices. The length of time that the sample was heated had no effect on TCE response. Lung and kidney samples, due to the low amounts of heme-containing proteins, yielded better responses when not heated at all.