AUTOMATED-DETERMINATION OF INORGANIC MERCURY IN BLOOD AFTER SULFURIC-ACID TREATMENT USING COLD VAPOR ATOMIC-ABSORPTION SPECTROMETRY AND AN INDUCTIVELY HEATED GOLD TRAP

Inorganic mercury (InoHg) in whole blood and erythrocytes was determin ed by cold vapour atomic absorption spectrometry (CVAAS) after overnig ht treatment with sulfuric acid at 45 degrees C and reduction with Sn- II in the acidic mixture. Total mercury (TotHg) was determined after d igestion with a mixture of nitric and perchloric acids. Mercury vapour was preconcentrated on an amalgamation trap made of gold wire. The me rcury was rapidly released by inductive heating of the trap. InoHg cou ld be determined specifically in the presence of methylmercury (MeHg). The concentration of MeHg could be calculated by subtracting the conc entration of InoHg from that of TotHg. Calculated concentrations of Me Hg in erythrocytes showed a strong correlation with the results of a g as chromatographic method, though a discrepancy in calibration was ind icated. The detection limits (3 s) in blood (0.5 g) were 0.06 ng g(-1) for TotHg and 0.04 ng g(-1) for InoHg and s(r) for a 5 ng g(-1) whole blood sample was 2% (n = 10) for both TotHg and InoHg.