title: Measurement by ICP-MS of lead in plasma and whole blood of lead workers and controls.
abstract: OBJECTIVE
  To test a simple procedure for preparing samples for measurement of lead in blood plasma (P-Pb) and whole blood (B-Pb) by inductively coupled plasma mass spectrometry (ICP-MS), to measure P-Pb and B-Pb in lead workers and controls, and to evaluate any differences in the relation between B-Pb and P-Pb between people.
  
  
  METHODS
  P-Pb and B-Pb were measured by ICP-MS in 43 male lead smelter workers and seven controls without occupational exposure to lead. For analysis, plasma and whole blood were diluted 1 in 4 and 1 in 9, respectively, with a diluted ammonia solution containing Triton-X 100 and EDTA. The samples were handled under routine laboratory conditions, without clean room facilities.
  
  
  RESULTS
  P-Pb was measured with good precision (CV = 5%) even at concentrations present in the controls. Freeze storage of the samples had no effect on the results. The detection limit was 0.015 microgram/l. The P-Pb was 0.15 (range 0.1-0.3) microgram/l in controls and 1.2 (0.3-3.6) micrograms/l in lead workers, although the corresponding B-Pbs were 40 (24-59) micrograms/l and 281 (60-530) micrograms/l (1 microgram Pb/I = 4.8 nmol/l). B-Pb was closely associated with P-Pb (r = 0.90). The association was evidently non-linear; the ratio B-Pb/P-Pb decreased with increasing P-Pb.
  
  
  CONCLUSIONS
  By means of ICP-MS and a simple dilution procedure, P-Pb may be measured accurately and with good precision down to concentrations present in controls. Contamination of blood at sampling and analysis is no major problem. With increasing P-Pb, the percentage of lead in plasma increases. In studies of lead toxicity, P-Pb should be considered as a complement to current indicators of lead exposure and risk.
authors.affiliation: Department of Occupational and Environmental Medicine, Lund University, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Schütz
authors.forename: I A
authors.initials: IA
authors.lastname: Bergdahl
authors.forename: A
authors.initials: A
authors.lastname: Ekholm
authors.forename: S
authors.initials: S
authors.lastname: Skerfving
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D006801:Humans; D007854:Lead / Q000097:blood*; D008297:Male; D013058:Mass Spectrometry / Q000379:methods; D008669:Metallurgy; D008875:Middle Aged; D016273:Occupational Exposure / Q000032:analysis*; D010949:Plasma; D012680:Sensitivity and Specificity
chemical_list: D007854:Lead