Mercury is a toxic environmental pollutant that can be deadly to humans. It is found in three different forms: the metallic element, inorganic salts and organic compounds. Elemental mercury can be released into the
atmosphere by natural occurrences such as volcanic eruptions, but the majority is produced by human activities. It has been estimated that coal fired power plants, waste incineration, metal processing and cement
production produce approximately 75% of the 5,500 tons of mercury that are released into the atmosphere each year [1]. Due to its high volatility, mercury becomes airborne very easily. Once in the atmosphere, it can travel huge distances before eventually being deposited in rivers or oceans. In aquatic environments, mercury is transformed into methyl mercury by both microorganisms and abiotic reactions. Methyl mercury becomes increasingly concentrated in the marine food chain, in a process referred to as biomagnification, and can reach extremely high levels in predatory fish such as swordfish, tuna, king mackerel and shark. Methyl mercury can make up more
than 90% of the total mercury in fish and seafood. The consumption of these fish and other marine organisms is the main route of human exposure to methyl mercury.