10.1594/PANGAEA.987318Pérez-Rodríguez, MartaMartaPérez-Rodríguez0000-0001-7139-3049Technische Universität BraunschweigBiester, HaraldHaraldBiesterTechnische Universität BraunschweigPANGAEA2026in-situ pumpsMercuryMethylmercuryparticleSouth Sandwich IslandsEvent labelDATE/TIMELATITUDELONGITUDEDEPTH, waterMercury, particulateMonomethylmercury, particulateIn situ pumpThermal decomposition amalgamation - atomic absorption spectrometer (TDA AAS), Milestone, DMA EVOGas chromatograph - cold vapor atomic fluorescence spectrometery (GC-CVAFS), Brooks Rand, Methylmercury Manual SystemPS133/1PolarsternGlobal marine biogeochemical cycles of trace elements and their isotopes (GEOTRACES)2022-10-22T15:51:21/2022-11-09T11:26:24Dataset10.1029/2025GB00876710.4319/lom.2012.10.681186 data pointstext/tab-separated-valuesCreative Commons Attribution 4.0 InternationalConcentrations of particulate total mercury (Hg) and monomethylmercury (MMHg) were determined in size-fractionated suspended particles collected in the Southern Ocean between 22 October and 9 November 2022 during the PS133/1 expedition. Particles were collected using battery-powered in situ large-volume pumps (McLane Research Laboratories, Inc. and Challenger Oceanic's Stand-Alone Pumping System, SAPS) equipped with 142 mm diameter filter holders (MULVFS style; Bishop et al., 2012). Pumps were deployed at depths ranging from 25 to 350 m. Each filter holder contained two filters for size fractionation: a 51 μm Sefar Petex screen (SEFAR GmbH)—acid-leached prior to the cruise—mounted above a pre-combusted QMA filter (nominal pore size ~2.2 μm), separating particle size classes of 2.2–51 μm and >51 μm. Particulate total mercury was quantified by thermal decomposition, amalgamation, and atomic absorption spectrophotometry (TDA–AAS) using a DMA-EVO Direct Mercury Analyzer (Milestone). MMHg concentrations were determined by gas chromatography–cold vapor atomic fluorescence spectrometry (GC–CVAFS) using a Brooks Rand methylmercury analysis system following acid digestion. Data are reported both as mass-specific concentrations (ng g⁻¹ of suspended particulate matter) and as volume-normalized concentrations (pmol L⁻¹), corrected for the volume of water filtered.-39.99797-24.84127-56.26666-51.28914Danish National Research Foundationhttps://doi.org/10.13039/501100001732DNRF145Danish Center for Hadal Research, HADALGerman Research Foundationhttps://doi.org/10.13039/501100001659528941462Controls of Primary Production on Southern Ocean Mercury Cycling (COPPSOM)German Research Foundationhttps://doi.org/10.13039/501100001659GPF 20-1_053Island Impact: Understanding the Regional Impact of South Georgia on Southern ACC Biogeochemistry and Ecosystem FunctionGerman Research Foundationhttps://doi.org/10.13039/501100001659GPF 20-2_024South Polar Carbon: Benthic Carbon Mineralization and Preservation in Southern Ocean Bathyal, Abyssal and Hadal Sediments