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A method for full speciation and determination of alkyllead and inorganic lead(II) in aqueous samples was developed. This was accomplished by in situ derivatization with deuterium-labeled sodium tetraethylborate NaB(C2D5)4 (DSTEB). The derivatization was carried out directly in the aqueous sample and the derivatives were extracted from the headspace by a solid-phase microextraction (SPME) fiber. The extracted analytes were then transferred to a GC/MS or a GC/FID for separation and detection. The research presented demonstrates that SPME and the derivatization reagent DSTEB can be used successfully for the speciation of Pb2+, Pb(CH3)3+, Pb(C2H5)3+, and Pb(C2H5)4 in water samples. All derivatives, Pb(C2D5)4, (CH3)3Pb(C2D5), (C2H5)3Pb(C2D5), and Pb(C2H5)4, are separated using an SBP-5 column. This method was applied to monitor degradation of tetraethyllead in water. This is the first report of ethylation by DSTEB for full speciation of methyllead, ethyllead, and inorganic lead compounds. This approach can be extended to other organometallic compounds as demonstrated for ethyltin speciation. This full speciation method will aid in monitoring occurrence, pathways, toxicity, and biological effects of these compounds in the environment. It is easily adopted for field analysis.

Lead is the most frequently quantitated toxic metal in biological matrixes. In this paper, a method is described for lead determination in whole blood and urine using solid-phase microextraction (SPME) gas chromatography. Lead ion is first derivatized with sodium tetraethylborate to form tetraethyllead, which is then extracted from the headspace over the sample by SPME. The analytical procedure was optimized for coating selection, pH, extraction time, and effect of salt. The relative standard deviation was less then 10% for both urine and blood samples. The limit of detection was 3 and 4 ppb; the limit of quantification is 5 and 10 ppb for urine and blood samples, respectively. Good linearity was found for both urine and blood samples when PDMS coating was used. The standard addition method was used for quantitation. Certified urine and blood samples were analyzed, and good accuracy was obtained.