Steiner says the treaty, which still requires ratification by at least 50 of the nations that sign on before becoming legally binding for those countries, could accomplish its aim of curbing harmful emissions of mercury anywhere from about 2025 to 2050. It would do that through banning new mercury mines and phasing out existing ones, imposing control measures on air emissions and regulating artisanal or small-scale gold mining.
"Essentially, what we have managed to do is to persuade the international community to send a very clear signal the use of mercury in industrial processes, in cosmetics, in medical equipment, is essentially over," Steiner told reporters in Geneva. "It doesn't mean that all mercury will disappear tomorrow."
But nations with artisanal and small-scale gold mining operations, one of the biggest sources of mercury releases, will only be required to draw up national plans within three years of the treaty entering force and then to reduce and if possible eliminate the use of mercury in such operations.
Mercury poses the greatest risk of nerve damage to pregnant women, women of child-bearing age and young children. It can also cause brain and kidney damage, language impairment and memory loss. There are no safe limits for the consumption of mercury and its compounds, according to the U.N.'s World Health Organization.
The treaty was named for the southern Japanese city of Minamata, where a severe neurological disorder caused by mercury poisoning was discovered in the late 1950s, caused by methylmercury escaping from the city's industrial wastewater.
The illness, now known as Minamata disease, sickened people who ate contaminated fish, killed hundreds and left many more badly crippled. About 12,000 people have demanded government compensation.