Polarized Zeeman-effect flameless atomic absorption spectrometry of cadmium, copper, lead, and manganese in human kidney cortex.

We used polarized Zeeman-effect flameless atomic absorption spectroscopy to quantitatively measure cadmium, copper, lead, and manganese in a nitric acid digest of lyophilized human kidney cortex. Within-run coefficients of variation for cadmium, copper, lead, and manganese, 15.3, 177.2, 84.2, and 56.3 microgram/L, respectively, were 4.1, 6.3, 3.7, and 5.6%, respectively. Between-run coefficients of variation were 6.9, 5.5, 5.9, and 6.3%, respectively, for cadmium, copper, lead, and manganese concentrations of 135.1, 12.8, 2.72, and 3.80 microgram/g, respectively. For cadmium, copper, lead, and manganese digest concentrations (mean +/- SE) of 15.3 +/- 0.6, 41.4 +/- 2.6, 9.4 +/- 0.6, and 20.9 +/- 0.4 microgram/L, respectively, the detection limits were 5.2 microgram/L for copper, 1.2 microgram/L for both cadmium and lead, and 0.8 microgram/L for manganese. Assays were linear to 75 microgram/L for cadmium, 100 microgram/L for manganese, and 200 microgram/L for copper and lead. Average analytical recoveries for the four metals ranged between 95 and 101%. Because these metals were quantitated in the same digest of kidney cortex, the values for each digest gave a trace-metal profile for each autopsy specimen.