Environmental Science

Atmospheric Mercury

Shortcomings with current atmospheric mercury instrumentation are limiting our ability to understand how mercury is transported and transformed in the atmosphere. We are developing improved instrumentation, allowing us to more accurately detect atmospheric mercury compounds.  View recent presentations about this instrumentation, or find papers and reports on this topic, or download datasets.

We have developed methods to quantify and identify oxidized mercury compounds via gas chromatography and mass spectrometry. Gas chromatography isolates and quantifies the constituent compounds of a sample, and mass spectrometry measures each compound’s molecular mass, allowing accurate identification. These exceptionally reactive compounds are not easy to keep in the gas phase, so we have created an ultra-inert handling system to provide maximum sample transmission.  Our 2016 paper describes the basics of this system.  We are now using it to characterize emissions from mercury permeation tubes used for calibration

We are also developing field-deployable calibrators that will allow automatic verification of ambient oxidized mercury measurements. Currently, no calibration system is well accepted for oxidized mercury, and very few field calibrations have been performed. Our calibrator uses multiple permeation tubes to allow calibration with a variety of compounds, and it has a built-in pyrolyzer to convert oxidized mercury compounds to elemental mercury on the fly, so oxidized mercury permeation rates can be checked with an elemental mercury detector. To learn more, read this interesting article or some recent presentations about this instrumentation.

Environmental Ecology