Palladium chloride enhancement of low-level mercury analysis

Marked improvement in the sensitivity for atomic absorption analysis of mercury was achieved by the presence of palladium chloride (PdCl2) in the analyte solution. Furthermore, this solution could be stored for later analysis without loss of mercury to the container or headspace. Filters for sampling airborne mercury were impregnated with 0.45% w/v PdCl2 solution so that they would adsorb the mercury vapors at low ambient concentrations. The collected mercury was removed with a solution containing 2% hydrogen peroxide and 2% nitric acid. An aliquot of the solution was analyzed in a graphite furnace on an atomic absorption spectrophotometer. The method appears suitable not only for sampling and analyzing airborne mercury but also for analyzing water samples.