Analysis of Total Mercury in Biological and Water Samples by an Ultrasensitive Kinetic Method
SourceA wet digestion has been developed to prepare biological and water samples for a kinetic determination of total mercury using an iodide-catalyzed reaction between cerium (IV) and arsenite (III). A mercury-free control, prepared using ion-exchange with a selective chelating resin, was used by adding mercury standards to make a calibration curve. Both inorganic and organic mercury can be determined by the method described either in biological or water samples containing mercury in the range of 0.05 to 2.0 µg per ml. The procedure can be used satisfactorily down to the 0.05-ppm level for urine and fresh water with an overall error of less than 5 percent. The method can also be employed for the determination of mercury in blood serum or seawater with an error of 10 percent or less and gives results which compare favorably with other procedures.