DETERMINATION OF MERCURY IN URINE BY ONLINE DIGESTION WITH A FLOW-INJECTION MERCURY SYSTEM

An accurate, reliable, simple and fully automated method was developed for on-line treatment of urine samples in a microwave digestion syste m and the determination of mercury using flow injection mercury system . Once bromate-bromide and hydrochloric acid were added, the entire sy stem operation occurs in a standalone manner. The organic mercury comp ounds were decomposed to inorganic mercury (II) ions at room temperatu re, and the determination of mercury by on-line microwave sample pretr eatment was performed with the flow injection mercury system. The syst em demonstrates exceptional accuracy for urine samples analyzed with c onventional flow injection cold vapor atomic absorption spectrometry. The linearity of the rprocedures range from 0.05 to 20 mu g/L. Good ag reement between measured and recommended values of mercury in urine re ference materials was obtained, Sample throughput was about 25 measure ments/hour. The relative standard deviation (%) at 5 mu g/L in urine s ample was 2 %. For three replicate measurements, 0.5 mL of urine is re quired. Urine samples from 10 non-exposed workers were analyzed in thi s study. Since the entire analytical process occurs In a closed system , risk of contamination and analyte loss is reduced, leading to improv ed analytical performance and laboratory productivity.