Occurrence and sorption properties of arsenicals in marine sediments

Patrik Fauser, Hans Sanderson, Rikke Susanne Vingborg Hedegaard, Jens Jørgen Sloth, Martin M. Larsen, Teddy Krongaard, Rossana Bossi, Jørn B. Larsen

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

The content of total arsenic, the inorganic forms: arsenite (As(III)) and arsenate (As(V)), the methylated forms: monomethylarsonic acid and dimethylarsinic acid (DMA), trimethylarsenic oxide, tetramethylarsenonium ion and arsenobetaine was measured in 95 sediment samples and 11 pore water samples from the Baltic Sea near the island of Bornholm at depths of up to 100 m. As(III+V) and DMA were detected in the sediment and As(III+V) was detected in the sediment pore water. Average total As concentration of 10.6 ± 7.4 mg/kg dry matter (DM) in the sediment corresponds to previously reported values in the Baltic Sea and other parts of the world. Existing data for on-site measurements of sorption coefficients (Kd) of arsenicals in marine and freshwater sediments show large variability from 1,000 L/kg. In this work, calculated sorption coefficients (Kd and Koc) for As(III+V) showed significant correlation with depth, dissolved oxygen (DO), salinity and sediment classification; for depths 9 mg/L and sand/silt/clay sediments the Kd was 118 ± 76 L/kg DM and for depths >70 m, salinity >11 %, DO <9 mg/L and muddy sediments the Kd was 513 ± 233 L/kg DM. The authors recommend using the found Kd value for arsenic in marine sediments when conditions are similar to the Baltic Sea. At locations with significant anthropogenic point sources or where the local geology contains volcanic rock and sulphide mineral deposits, there may be significantly elevated arsenic concentrations, and it is recommended to determine on-site Kd values.
Original languageEnglish
JournalEnvironmental Monitoring and Assessment
Volume185
Issue number6
Pages (from-to)4679-4691
ISSN0167-6369
DOIs
Publication statusPublished - 2013

Keywords

  • Arsenical
  • Marine sediments
  • Measurements
  • Sorption coefficient
  • Kd
  • Baltic Sea

Cite this

Fauser, P., Sanderson, H., Hedegaard, R. S. V., Sloth, J. J., Larsen, M. M., Krongaard, T., Bossi, R., & Larsen, J. B. (2013). Occurrence and sorption properties of arsenicals in marine sediments. Environmental Monitoring and Assessment, 185(6), 4679-4691. https://doi.org/10.1007/s10661-012-2896-2