Year: 2026
Type: article
Abstract: Mercury is a persistent pollutant with significant public health impacts in polar regions where fish consumption drives human exposure. Atmospheric oxidation pathways control where mercury deposits globally, but the lack of molecular-level observations of oxidized mercury products has hindered the validation of proposed chemical mechanisms. Here, we show the in-situ online detection of individual mercuric halides (HgCl2, BrHgCl, HgBr2, ClHgI, BrHgI, and HgI2) in the polar boundary layer using atmospheric pressure chemical ionization mass spectrometry. Our observations identify HgBr2 as the dominant oxidized mercury species at both poles, while HgCl2 and other halides were also observed in Antarctica. The observed speciation diverges from current model predictions, which favor HgCl2 and HOHgBr as dominant oxidized forms. Our results show that real-time molecular measurements can substantially advance global mercury monitoring and improve the chemical models used to assess environmental policies and predict deposition patterns. Researchers report real-time molecular detection of oxidized mercury species in the polar atmosphere, revealing discrepancies with current models and advancing understanding of neurotoxic mercury cycling in sensitive ecosystems.
Source: Nature Communications
Institutions: University of Helsinki, Cyprus Institute, Consejo Superior de Investigaciones Científicas, Instituto de Astrofísica de Andalucía, Instituto de Química Física Blas Cabrera, Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, University of Leeds, École Polytechnique Fédérale de Lausanne, University of Tartu
Language: English
Subfield: Health, Toxicology and Mutagenesis
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $6,990
Funders: National Science Foundation, U.S. Department of Energy, Helsingin Yliopisto, European Commission, École Polytechnique Fédérale de Lausanne, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Ministry of Earth Sciences, Paul Scherrer Institut, Ministerio de Ciencia e Innovación, Swiss Polar Institute, HORIZON EUROPE Framework Programme, Consejo Superior de Investigaciones Científicas, Agencia Estatal de Investigación
Awards: G1175115578, G1381791653, G1855990336, G1862802290, G210041235, G2114305129, G2262748287, G2309174360, G2551911579, G2601397997, CLOSING THE GAP ON UNDERSTUDIED AEROSOL-CLIMATE PROCESSES IN THE RAPIDLY CHANGING CENTRAL ARCTIC, G279363373, G300979063, G3202082471, G34346518, G3480869486, G3518538256, G3681454997, G3691132267, G378677568, G4042783231, G4051261263, G4212250524, G425668148, G430777504, G463062595, Eastern Mediterranean and Middle East – Climate and Atmosphere Research Centre, International Trade, G5080475149, G5421974903, G5894067328, G6080697404, Measurement-Based understanding of the aeRosol budget in the Arctic and its Climate Effects, G6960590981, Climate relevant interactions and feedbacks: the key role of sea ice and snow in the polar and global climate system, G8193250338, G8384565734, G8463653689, G855041801, Non-CO2 Forcers and their Climate, Weather, Air Quality and Health Impacts, G8921410818, G99296377
OpenAlex ID: W7151217280