Simple screening technique for determination of adsorbed and absorbed mercury in particulate matter in atmospheric and aquatic environment

Magdalena Bełdowska; Dominika Saniewska; Karolina Gębka; Urszula Kwasigroch; Ewa Korejwo; Justyna Kobos

doi:10.1016/j.talanta.2018.01.082

Simple screening technique for determination of adsorbed and absorbed mercury in particulate matter in atmospheric and aquatic environment

Talanta. 2018 May 15:182:340-347. doi: 10.1016/j.talanta.2018.01.082. Epub 2018 Feb 1.

Authors

Magdalena Bełdowska¹, Dominika Saniewska², Karolina Gębka², Urszula Kwasigroch², Ewa Korejwo², Justyna Kobos²

Affiliations

¹ Institute of Oceanography, University of Gdańsk, Al. Pilsudskiego 46, 81-378 Gdynia, Poland. Electronic address: m.beldowska@ug.edu.pl.
² Institute of Oceanography, University of Gdańsk, Al. Pilsudskiego 46, 81-378 Gdynia, Poland.

PMID: 29501162
DOI: 10.1016/j.talanta.2018.01.082

Abstract

The threat connected to mercury results from its capacity to be transported over long distances and its ability to bioaccumulate and biomagnify in the trophic chain, making it a global problem. Humans are situated at the top of the trophic ladder, and excess mercury manifests itself mainly in the onset of neurological conditions. The toxicity of mercury, as well as its residence time, depends on the form in which it occurs. However, analysis of mercury speciation is time-consuming and poses a high risk of additional or negative contamination. Hence, the mercury thermodesorption method, and particularly its use for fractionating Hg, offers many new possibilities. Here, the thermodesorption technique was applied to the determination of mercury fraction in particulate matter using a DMA-80 direct mercury analyser (Milestone, Italy). The presented method allows direct (without prior mineralisation) determination of labile and stabile mercury fractions within a relatively short time. Heating sample in subsequent temperatures enables determination the share of mercury adsorbed on the surface (mainly associated with halogenides (Hg_ads1) and HgSO₄/HgO/HgF₂ (Hg_ads2), as well as absorbed within the suspended particulate organic matter (Hg_abs), in a relatively short time. This fractionation is of great importance in terms of estimating the transfer of mercury to and along the trophic chain. This method determines the contribution of two stable mercury fractions:: HgS and residual Hg, strongly bound to particulate matter matrix (Hg_res). The novelty of this technique is also its joint ability to determine gaseous mercury bound to airboirne particulate matter, which will enable better understand Hg cycling in the atmosphere as well as mercury fraction in dry deposition flux. This method enables assessment of global mercury circulation in environment.

Keywords: Absorption Hg; Adsorption Hg; Fractionation; Gaseous Hg; Mercury; Thermal desorption.