Mercury Analysis and Speciation in Environmental Samples

Mercury occurs naturally in the Earth’s crust principally as the ore, cinnabar, HgS. Mercury is quite different from other metals in several respects: (i) it is the only metal that is liquid at room temperature; (ii) it is the only metal that boils below 650°C; (iii) it is quite inert chemically, having a higher ionization potential than any other electropositive element with the sole exception of hydrogen; (iv) it exists in oxidation states of zero (Hg°) and 1 (Hg₂2+) in addition to the expected state of 2 (Hg2+). Mercury forms alloys (“amalgams”) with many metals. Mercury and its chemical derivatives are extremely hazardous. Since the early 1960s, the growing awareness of environmental mercury pollution (e.g. the Minamata tragedy resulting from methyl-mercury poisoning) has stimulated the development of more accurate, precise and efficient methods of determining mercury and its compounds in wide variety of matrices.