Sampling and Determination of Particulate Mercury in Ambient Air: A Review

Total particulate mercury (TPM) may constitute, in general, a small percentage by mass of total atmospheric mercury, but under certain conditions it can be a very significant form of atmospheric Hg, and play an important role in the deposition of mercury to terrestrial and aquatic cosystems. To understand the cycling and distribution of mercury in the environment, accurate determination of the total concentration and speciation of TPM are necessary. This article provides a review of scientific and technical literature published in the past 5 yr pertaining to sampling and analytical methodologies for the determination and chemical speciation of TPM in ambient air. Sampling methods discussed include the conventional filtration method and the diffusion denuder-based technique. Analytical techniques, such as gold-amalgamation/cold-vapor spectrometry, and nuclear methods, are summarized.