IMPROVING THE DETERMINATION OF MERCURY IN ENVIRONMENTAL-SAMPLES USINGA DEDICATED FLOW-INJECTION MERCURY SYSTEM

A procedure for the determination of mercury in environmental samples using a dedicated Flow Injection Mercury System (FIMS) is discussed. T he flow injection technique automates the generation of cold vapor mer cury, providing high sample throughput, with reduced sample and reagen t consumption. Using a dedicated system eliminates the requirement for a separate AA spectrometer. This system consists of a FIAS unit equip ped with mercury lamp, quartz cell, and mercury detector. The light fr om the mercury source is passed through an absorption cell and then on to the detector. The detection limit of mercury in drinking waters, us ing the FIMS, is 10 ng/L Hg. This represents a 20-fold improvement in the mercury detection limit previously obtained with the FIAS system. The EPA-approved flow injection method permits the automatic determina tion of mercury with sample throughput equal to 120 determinations per hour. The performance of the FIMS when running water samples is repor ted.