Development and field application of a passive sampler for atmospheric mercury

Abstract

In this study, a passive sampler for gaseous elemental mercury (GEM) was developed and applied to field monitoring. Three Radiello® diffusive bodies with iodineimpregnated activated carbon (I-IAC) as a Hg adsorbent were placed in an opaque acrylic external shield with a stainless steel lid. The performance of the passive sampler was evaluated at seven monitoring sites in South Korea. Hg uptake mass by the passive sampler linearly increased as the deployment time increased up to four months. The reproducibility of the sampler uptake mass for the different deployment periods was also good, and the average relative standard deviation calculated for the three adsorbents in one passive sampler was 9%. Using the Hg concentration measured by an active sampler, an experimental sampling rate (SR) of 0.082 m3 day-1 was obtained. It was shown that the experimental SR was significantly affected by meteorological parameters, and a calibration equation was successfully derived based on wind speed, temperature, and relative humidity. With the calibrated SRs, there was a significant correlation between the active and passive Hg concentrations. When the passive samplers were deployed in an industrial district, the GEM concentration showed very large spatial variation, suggesting its potential for application in future field monitoring.