On-line pre-concentration and determination of lead in potable water by flow injection atomic absorption spectrometry

Abstract

A flow injection system incorporating a micro-column of activated alumina was used in conjunction with flame atomic absorption spectrometry for the pre-concentration and determination of lead in drinking waters. The analyte was deposited on the alumina micro-column (basic form of alumina) during the sampling stage and elution was effected by injection of nitric acid (250 µl, 2 M). The procedure was successfully applied to a range of water samples and the accuracy was assessed through recovery experiments, the analysis of a certified reference water and by independent analyses by inductively coupled plasma mass spectrometry. The limit of detection based on a sample volume of 25 ml (sampling time 5 min at 5 ml min–1) was 0.36 µg l–1 and the relative standard deviations at 40 and 4 µg l–1 were 1.4 and 12%, respectively.