DETERMINATION OF TRACE TOTAL GASEOUS MERCURY IN THE ATMOSPHERE BY TWO-STAGE GOLD AMALGAMATION COLD VAPOR ATOMIC FLUORESCENCE SPECTROSCOPY

A new procedure to determine trace total gaseous mercury (TGM) in the atmosphere by two-stage gold amalgamation cold vapor atomic fluorescence spectroscopy was set up. The detection limit of this method is below 2 pg. When air has been pulled through a sampling trap at the flow rate of 0.2 ~ 0.4 L·min~(-1) for 12 ~ 48 hours, the sampling efficiency of 99% and precision of 9.63% are obtained, respectively. The thermal desorption efficiency of samples is 99% through two analysis heating-cycles. This method also can be used to analyze trace mercury contents in other environmental samples.