Methylmercury extraction from aquatic sediments: A comparison between manual, supercritical fluid and microwave-assisted techniques

Abstract During recent decades the speciation of organomercurials has been a challenge to analytical laboratories dealing with environmental studies. Although easily detectable levels of organomercurials, and especially of methylmercury, are found in marine predators and biota, sediments are of fundamental interest as they provide a tool for assessing the impact of anthropogenic emissions on the environment. However, as in many other analytical problems, the sample-preparation stage has received less attention than the determination stage itself, although it is universally recognised that it determines the reliability of the analytical results. Recent developments in sample preparation have now been applied to the methylmercury problem. In this article a direct comparison is made between manual extraction, supercritical fluid extraction and microwave-assisted extraction. Each technique was used to extract methylmercury from polluted sediments. The efficiencies, merits and disadvantages of each technique are discussed.

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