Marine versus Continental Sources of Iodine and Selenium in Rainfall at Two European High-Altitude Locations

Environ Sci Technol. 2019 Feb 19;53(4):1905-1917. doi: 10.1021/acs.est.8b05533. Epub 2019 Feb 6.

Abstract

The essential elements selenium (Se) and iodine (I) are often present in low levels in terrestrial diets, leading to potential deficiencies. Marine I and Se emissions and subsequent atmospheric wet deposition has been suggested to be an important source of I and Se to soils and terrestrial food chains. However, the contribution of recycled moisture of continental origin to I and Se to precipitation has never been analyzed. Here we report concentrations and speciation of I and Se, as well as of bromine (Br), sulfur (S), and DOC-δ13C signatures for weekly collected precipitation samples (in the period of April 2015 to September 2016) at two high altitude sites, i.e., Jungfraujoch (JFJ; Switzerland) and Pic du Midi (PDM; France). Analysis of precipitation chemistry and moisture sources indicate combined marine and continental sources of precipitation and Se, I, Br, and S at both sites. At JFJ, concentrations of I and Se were highest when continental moisture sources were dominant, indicating important terrestrial sources for these elements. Furthermore, correlations between investigated elements and DOC-δ13C, particularly when continental moisture source contributions were high, indicate a link between these elements and the source of dissolved organic matter, especially for I (JFJ and PDM) and Se (JFJ).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Altitude
  • Environmental Monitoring
  • France
  • Iodine*
  • Selenium*
  • Switzerland

Substances

  • Iodine
  • Selenium