Determination of lead and other trace element species in blood by size exclusion chromatography and inductively coupled plasma/mass spectrometry

The combination of liquid chromatography and inductively coupled plasma/mass spectrometry (ICP/MS) was employed in an exploratory study to determine lead and other trace element species in blood components. In human blood serum, lead was found in at least three molecular weight fractions at greater than 600,000, 260,000, and 140,000. The major part of lead was coincident with the main copper signal at a molecular weight of 140,000. This fraction, binding both copper and lead, was proven to be ceruloplasmin by the application of an immunological reaction prior to chromatographic separation. In rat serum, lead could be detected in four fractions with molecular weights of greater than 600,000, 400,000, 145,000, and 11,000. In human red blood cell hemolysate, the major fraction of lead was found at 250,000, with minor fractions at 140,000 and at 30,000 together with iron in hemoglobin and zinc in carbonic anhydrase. In rat red blood cell hemolysate, lead was detected at greater than 600,000, 145,000, 30,000, and 11,000. Lead isotope ratios were determined in lead binding protein fractions with a precision of +/- 10%. The detection limit for lead in protein fractions was 0.15 micrograms.L-1.