DETERMINATION OF ENVIRONMENTAL LEAD USING CONTINUOUS-FLOW MICROWAVE DIGESTION ISOTOPE-DILUTION INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY

A commercial now-through microwave system was successfully applied as an alternative sample preparation procedure for lead determinations us ing isotope dilution inductively coupled plasma quadrupole mass spectr ometry, Sample is introduced as a slurry and then injected into a carr ier stream which is continually flowing through the system, As configu red, the sample dissolution is sequential, taking about 10 min/sample. This closed system is easy to use and produces lon blanks, thus provi ding a viable alternative to the direct introduction of untreated samp les, which can degrade analytical results, Leaves, air filters, urine, sludge, dust, and paint standard reference materials previously certi fied for lead using isotope dilution mass spectrometry (IDMS) were use d to evaluate the accuracy of this automated sample preparation device . Lead concentrations in the nanograms to micrograms per gram range we re accurately determined when compared with the certified value and pr evious IDMS results.