RESUMEN
Now that the level of concern for a toxic blood lead concentration is 0.482 mumol/L (10 micrograms/dL), laboratories must meet new requirements to shorten analysis times and increase accuracy and precision of blood lead determinations. We used a matrix-matching method to estimate the lead concentration in blood by graphite furnace atomic absorption spectroscopy (GFAAS). For CDC proficiency samples and the NIST-Certified Blood Reference standard, the performance of this method compared favorably with that of previously published GFAAS methods and of the anodic stripping voltammetric method routinely used in our laboratory. At lead concentrations of 0.242 mumol/L (5.01 micrograms/dL) and 1.478 mumol/L (30.63 micrograms/dL), within-run CVs were 2.78% and 0.68%, respectively; between-run CVs were 4.9% and 1.35%. In 52 study samples with lead content ranging from 0.097 to 3.812 mumol/L (2 to 79 micrograms/dL), 87% of results by the matrix-modified method were within 0.048 mumol/L (1 microgram/dL) of consensus values.
