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Updated: Jul 12, 2026
09:33
An Anaerobic Biosensor Assay for the Detection of Mercury and Cadmium
Published on: December 17, 2018
Methylation of selenium in the aquatic environment
Science (New York, N.Y.)
|June 11, 1976
Summary
Microorganisms in lake sediment convert inorganic and organic selenium into volatile compounds. This microbial transformation is crucial for selenium
Area of Science:
- Environmental microbiology
- Biogeochemical cycling
Background:
- Selenium is an essential trace element with complex environmental behavior.
- Microbial transformations significantly influence the fate and transport of selenium in ecosystems.
Purpose of the Study:
- To investigate the microbial conversion of selenium compounds in lake sediment.
- To identify the volatile selenium species produced by microorganisms.
Main Methods:
- Incubation of lake sediment with inorganic and organic selenium compounds.
- Analysis of volatile selenium products using gas chromatography.
- Isolation and testing of pure microbial cultures (bacteria and fungi).
Main Results:
- Microorganisms in lake sediment converted selenium to volatile forms, including dimethyl selenide and dimethyl diselenide.
- Pure cultures of bacteria and fungi also demonstrated this selenium volatilization capability.
- An unidentified volatile selenium compound was also detected.
Conclusions:
- Microbial activity in lake sediments is a key driver for the volatilization of selenium.
- These microbial transformations play a significant role in the environmental cycling and transport of selenium.
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