Determination of triethyllead, diethyllead and inorganic lead ions in urine by hydride generation flameless atomic absorption spectrometry.

Abstract

A technique utilizing hydride generation-atomic absorption spectro-photometry was established for the fractional determination of triethyllead (Et3Pb+), diethyllead (Et2Pb2+), inorganic lead (Pb2+) and total lead (total Pb) in the urine.The extraction of the target lead compounds from the urine required the pre-treatment of urine samples.Sample solutions were prepared by the use of 0.5 M DL-Malic acid for the generation of Et3Pb+, by the use of 0.75 M H202-0.004 M HCl04 for the generation of Et2Pb2+, and by the use of 1.6 M DL-Malic acid-0.05 M K2Cr207 for the genera-tion of Pb2+; and sodium borohydride was then added to the so treated sample solu-tions. The lead hydrides were once fixed in a U-trap cooled with liquid nitrogen beforehand, and the respective hydrides were then fractionated by volatization; and the fractions were atomized in a quartz cell heated to 1000°C for atomic absorption spectrophotometry.The recovery rates by this technique from 5 replications proved to be 99.7% for Et3Pb+, 97.3% for Et2Pb2+, 91.4% for Pb2+, and 95.9% for total Pb, with the coefficients of variation being 5.6% for Et3Pb+, 7.5% for Et2Pb2+, 2.1% for Pb2+ and 2.9% for total Pb. The detection limits of this technique also proved to be 0.005 μgPb for Et3Pb+ and Et2Pb2+ and 0.1 μgPb for Pb2+.