By Daniel Wallis NAIROBI, Feb 5 (Reuters) - Industrialised nations should agree binding rules to cut use of the toxic heavy metal mercury and speed up plans to curb exports to the developing world, environmental activists said on Monday. The United States and the European Union have substantially cut their use of mercury - used in processes ranging from mining to electronics, plastics and chemicals manufacturing - but other countries are using it more and more. "Governments must now agree tough and binding rules," Elena Lymberidi of the Zero Mercury coalition said in a statement ahead of a Kenya meeting of the world's environment ministers. She urged global action and said the U.N. Environment Programme (UNEP) needed to get tough. Mercury, also known as quicksilver, is highly toxic and exposure can damage the brain, nervous system and foetuses. World consumption of mercury has stabilised over the last five years at about 3,500 tonnes a year with China and India the top two importers. The EU, the world's largest exporter, wants to phase out its use and impose an export ban by 2011, but experts say before that the market could be flooded with mercury as suppliers rush to shift stocks. Campaigners criticise governments for backing just voluntary agreements rather than legally binding ones and want global usage cut by 70 percent by 2017. "Mercury is not potato chips, and we should not be trading it on the world market as if it is," David Lennet, a senior adviser to the U.S.-based Natural Resources Defense Council, told Reuters. "We need a binding legal instrument." Almost a third of the world's supply is used by small scale gold mines. Recent gains in the price of gold has bolstered mercury demand and lifted prices. In the 1990s a kg (2.2 lb) cost between $4-5 compared with more than $12/kg now.
