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Updated: Jun 12, 2026
09:33
An Anaerobic Biosensor Assay for the Detection of Mercury and Cadmium
Published on: December 17, 2018
Dietary selenium's protective effects against methylmercury toxicity
Nicholas V C Ralston1, Laura J Raymond
1Energy & Environmental Research Center, University of North Dakota, 15 North 23rd Street, Grand Forks, ND 58202, USA. nralston@undeerc.org
Toxicology
|June 22, 2010
Summary
Dietary selenium (Se) status protects against methylmercury (MeHg) toxicity by preventing inhibition of essential selenium-dependent enzymes. Adequate Se intake can even reverse MeHg
Area of Science:
- Environmental Toxicology
- Nutritional Biochemistry
- Neuroscience
Background:
- Dietary selenium (Se) status is inversely correlated with methylmercury (MeHg) toxicity.
- Se-enriched diets mitigate and can reverse MeHg-induced toxicity.
- MeHg is a potent inhibitor of Se-dependent enzymes (selenoenzymes).
Purpose of the Study:
- To elucidate the protective mechanisms of selenium against methylmercury toxicity.
- To understand the role of selenoenzymes in mitigating mercury's neurotoxic effects.
- To inform regulatory strategies for protecting child health from mercury exposure.
Main Methods:
- Review of existing literature on Se-MeHg interactions.
- Analysis of enzyme inhibition mechanisms.
- Examination of epidemiological data on human populations exposed to mercury.
Main Results:
- MeHg irreversibly inhibits selenoenzymes crucial for preventing oxidative damage, particularly in the brain.
- High Se intake protects against MeHg toxicity by ensuring adequate selenoenzyme function.
- Maternal MeHg exposure in low-Se environments is linked to adverse child outcomes, while Se-rich fish consumption is associated with improved child IQs.
Conclusions:
- Selenium's protective effect against MeHg toxicity is mediated by its essential role in selenoenzyme function.
- Dietary selenium levels critically influence the neurotoxic potential of mercury exposure.
- Regulatory guidance should consider Se-Hg ratios in food sources, especially for vulnerable populations.
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