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 exploritory 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 > 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 > 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 > 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-mu-g.L-1.