Micromethod for lead determination in whole blood by atomic absorption, with use of the graphite furnace.

I describe a micro-scale method for determining lead in whole blood by utilizing a graphite furnace. Sample pretreatment consists of fivefold dilution with a dilute surfactant. The method is directly calibrated with lead standards prepared in dilute HNO3. To eliminate a small, nonspecific absorption signal from the blood matrix, simultaneous background correction is used. Interlaboratory comparison with a flame atomic absorption technique that requires extraction yielded high correlation (r equal to 0.98). Within-run precision (coefficient of variation) ranged from 2 to 4 percent. Lead in blood can be accurately measured in as little as 20 mul of blood, hence the method is suitable for routine laboratory use and for pediatric screening.