Biomonitoring method for the simultaneous determination of cadmium and lead in whole blood by electrothermal atomic absorption spectrometry for assessment of environmental exposure

Abstract

The aim of this work is to propose a biomonitoring method for the simultaneous determination of Cd and Pb in whole blood by simultaneous electrothermal atomic absorption spectrometry for assessment of environmental levels. A volume of 200 μL of whole blood was diluted in 500 μL of 0.2% (w v −1) Triton ® X-100 + 2.0% (v v −1) HNO 3. Trichloroacetic acid was added for protein precipitation and the supernatant analyzed. A mixture of 250 μg W + 200 μg Rh as permanent and 2.0% (w v −1) NH 4H 2PO 4 as co-injected modifiers were used. Characteristic masses and limits of detections ( n = 20, 3 s) for Cd and Pb were 1.26 and 33 pg and 0.026 μg L −1 and 0.65 μg L −1, respectively. Repeatability ranged from 1.8 to 6.8% for Cd and 1.2 to 1.7% for Pb. The trueness of method was checked by the analysis of three Reference Materials: Lyphocheck ® Whole Blood Metals Control level 1 and Seronorm™ Trace Elements in Whole Blood levels 1 and 2. The found concentrations presented no statistical differences at the 95% confidence level. Blood samples from 40 volunteers without occupational exposure were analyzed and the concentrations ranged from 0.13 to 0.71 μg L −1 (0.32 ± 0.19 μg L −1) for Cd and 9.3 to 56.7 μg L −1 (25.1 ± 10.8 μg L −1) for Pb.