US EPA

5020554 

Journal Article 

Rapid pre-concentration of mercury in solids and water for isotopic analysis 

Janssen, SE; Lepak, RF; Tate, MT; Ogorek, JM; Dewild, JF; Babiarz, CL; Hurley, JP; Krabbenhoft, DP 

2019 

Yes 

Analytica Chimica Acta
ISSN: 0003-2670
EISSN: 1873-4324 

1054 

95-103 

English 

30712597 

10.1016/j.aca.2018.12.026 

WOS:000457244900009 

The precise quantification of mercury (Hg) stable isotope compositions in low concentration or dilute samples poses analytical challenges due to Hg mass limitations. Common Hg pre-concentration procedures require extended processing times, making rapid Hg stable isotope measurements challenging. Here we present a modified pre-concentration method that combines commonly used Hg reduction and gold trap amalgamation followed by semi-rapid thermal desorption (less than 1 h) and chemical trapping. This custom designed system was demonstrated to perform adequately on multiple trapping matrices including a new bromine monochloride (BrCl) wet oxidant trap (40% 3HNO3:BrCl), capable of trapping consistently in 2 mL volume over a wide range of Hg masses (5-200 ng). The procedure was also shown to work effectively on natural matrices, waters and sediments, producing comparable isotope results to the direct digestion analyses. Here, we present a method that can effectively triple sample throughput in comparison to traditional procedures, and also access lower concentration matrices without compromising the accuracy or precision of Hg isotope measurements.