Speciation and toxicity: mercury and associated compounds

Mercury is a toxic heavy metal abundant on earth and found everywhere in na ture. Its mineral and metalorganic compounds have many industrial applicati ons. Toxicity is depending on the chemical structure (organic or inorganic) and on the solubility properties of the various compounds. Mercury can com bine to carbon to give extremely toxic metalorganic compounds. The most tox ic species are the alkylated (methylated and ethylated) ones. A metabolisat ion scheme for man is proposed; metabolites, biological targets, detoxifica tion and intoxication processes are mentioned. All forms of mercury are tox ic for human beings and ecosystems; their toxicity is variable and depends on the nature of the compound. Consequently, it is of great importance to t ake speciation into account when designing a method to monitor environmenta l nutritional or occupational exposure to mercury by measurement of the ele ment in blood and urine.