Determination of lead in aqueous samples as the tetramethyl derivative by atomic absorption spectrometry.
Anal Chem 1982 May; 54(6):872-875
A method was presented for the determination of lead (7439921) in aqueous samples. Lead was extracted into chloroform as the dithiocarbamate complex followed by solvent evaporation and methylation of the residue with methyllithium to form tetramethyllead. A short column of Porapak-Q was used to trap the analyte vapor which was eluted from the column into a quartz furnace atomic absorption detector. At the 50 nanograms/milliliter (ng/ml) level a relative standard deviation of 6.8 percent was obtained. The detection range was from 5 to 200ng. The accuracy of the method was tested using Environmental Protection Agency samples. When running these samples it was necessary to use ammonium-pyrrolidine- dithiocarbamate as the chelating agent as sodium- diethyldithiocarbamate readily decomposed in acidic solutions. Ammonium-pyrrolidine-dithiocarbamate works equally well, but is slow to dissolve in water. No significant changes were noted in the slope or linearity of the calibration curve with this change in chelating agent. The authors conclude that the results show that an extraction/methylation/trapping procedure is a viable approach to lead determination.
NIOSH-Publication; NIOSH-Grant; Grants-other; Analytical-methods; Chemical-analysis; Analytical-chemistry; Lead-compounds; Atomic-absorption-spectrometry
Chemistry University of Cincinnati Department of Chemistry Cincinnati, Ohio 45221
Other Occupational Concerns; Grants-other
University of Cincinnati, Cincinnati, Ohio