Ethylmercury (sometimes ethyl mercury) is a cation composed of an organic CH<sub>3</sub>CH<sub>2</sub>— species (an ethyl group) bound to a mercury(II) centre, making it a type of organometallic cation, and giving it a chemical formula C<sub>2</sub>H<sub>5</sub>Hg<sup>+</sup>. The main source of ethylmercury is thiomersal. In these compounds, Hg(II) has a linear or sometimes trigonal coordination geometry. Given the comparable electronegativities of mercury and carbon, the mercury-carbon bond is described as covalent.

Toxicity

The toxicity of ethylmercury is well studied. Risk assessment for effects on the human nervous system have been made by extrapolating from dose-response relationships for methylmercury. In monkeys, it clears from brain tissue with a half-life of 24 days and blood in 7 days.

It is a fungicide but has been banned from use in the U.S. on food grain and even on seeds only used to grow crops.

Public health concerns

Concerns based on extrapolations of the effect of methylmercury caused thimerosal to be removed from U.S. childhood vaccines in 1999, but it remains in use in all multi-dose vaccines and flu shots (though many single-use vaccines without thimerosal are available). Researchers have argued that risk assessments based on methylmercury were overly conservative in light of observations that ethylmercury is eliminated from the body and the brain significantly faster than methylmercury.

See also

  • Diethylmercury
  • Mercury poisoning

References and notes

Further reading

<!--Deadlinks replaced by more useful, pertinent sources. Some links moved to Further reading, because adequately important. Melissa Kaplan site was self-published, listing no sources of information, and so a non-authoritative list and not a responsible entry for an encyclopedia. The Australian information page made no mention of Ethylmercury, and such general pages should appear at the Mercury and mercury toxicity pages, and not here.-->

  • EPA Organic Mercury TEACH Chemical Summary, 2007.
  • EPA Chemistry Dashboard, Ethyl Mercury Ion, 2017.

<!--DEAD LINK, RETURN ONLY IF FOUND SPECIFICALLY RELEVANT TO THIS ARTICLE: * ATSDR - ToxFAQs: Mercury-->

  • ATSDR Toxicological Profile for Mercury, search "Organic Mercury".

<!--DEAD LINK, RETURN ONLY IF FOUND SPECIFICALLY RELEVANT TO THIS ARTICLE: * ATSDR - Public Health Statement: Mercury-->

<!--DEAD LINK, DECADE OLD, AND AS FOCUSED ON METALLIC MERCURY, IRRELEVANT TO THIS ARTICLE: * ATSDR - ALERT! Patterns of Metallic Mercury Exposure, 6/26/97

  • [https://web.archive.org/web/20030802024248/http://www.atsdr.cdc.gov/MHMI/mmg46.html ATSDR Medical Management Guidelines for Mercury (Note: general reference, no mention of ethylmercury).-->

<!--IRRELEVANT TO THIS ARTICLE, ABSOLUTELY NO MENTION OF ETHYLMERCURY: * National Pollutant Inventory - Mercury and compounds Fact Sheet-->

<!--NOT ENCYCLOPEDIC/SELF-PUBLISHED: * Anapsid.org - 'Common Sources of Ethylmercury: Products containing ethyl mercury thiosalicylic acid as a preservative', compiled by Melissa Kaplan-->