Quantification of methylated selenium, sulfur, and arsenic in the environment

Bas Vriens; Adrian A Ammann; Harald Hagendorfer; Markus Lenz; Michael Berg; Lenny H E Winkel

doi:10.1371/journal.pone.0102906

Quantification of methylated selenium, sulfur, and arsenic in the environment

PLoS One. 2014 Jul 21;9(7):e102906. doi: 10.1371/journal.pone.0102906. eCollection 2014.

Authors

Bas Vriens¹, Adrian A Ammann², Harald Hagendorfer³, Markus Lenz⁴, Michael Berg⁵, Lenny H E Winkel¹

Affiliations

¹ Department of Water Resources and Drinking Water, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology, Zürich, Switzerland.
² Department of Environmental Toxicology, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.
³ Department of Thin Films and Photovoltaics, Swiss Federal Institute for Material Science and Technology, Dübendorf, Switzerland.
⁴ Institute for Ecopreneurship, School of Life Science, University of Applied Sciences and Arts Northwestern Switzerland, Muttenz, Switzerland; Department of Environmental Technology, Wageningen University, Wageningen, The Netherlands.
⁵ Department of Water Resources and Drinking Water, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.

Abstract

Biomethylation and volatilization of trace elements may contribute to their redistribution in the environment. However, quantification of volatile, methylated species in the environment is complicated by a lack of straightforward and field-deployable air sampling methods that preserve element speciation. This paper presents a robust and versatile gas trapping method for the simultaneous preconcentration of volatile selenium (Se), sulfur (S), and arsenic (As) species. Using HPLC-HR-ICP-MS and ESI-MS/MS analyses, we demonstrate that volatile Se and S species efficiently transform into specific non-volatile compounds during trapping, which enables the deduction of the original gaseous speciation. With minor adaptations, the presented HPLC-HR-ICP-MS method also allows for the quantification of 13 non-volatile methylated species and oxyanions of Se, S, and As in natural waters. Application of these methods in a peatland indicated that, at the selected sites, fluxes varied between 190-210 ng Se·m(-2)·d(-1), 90-270 ng As·m(-2)·d(-1), and 4-14 µg S·m(-2)·d(-1), and contained at least 70% methylated Se and S species. In the surface water, methylated species were particularly abundant for As (>50% of total As). Our results indicate that methylation plays a significant role in the biogeochemical cycles of these elements.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Arsenic / analysis*
Chromatography, High Pressure Liquid
Environment*
Selenium / analysis*
Sulfur / analysis*
Tandem Mass Spectrometry
Trace Elements / analysis*
Volatilization

Substances

Trace Elements
Sulfur
Selenium
Arsenic

Grants and funding

This work was funded by the Swiss National Science Foundation (http://www.snf.ch) (SNF PP00P2_133619 and 200020_138210). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.