By JOHN HEILPRINGENEVA (AP) â¿¿ A new and legally binding international treaty to reduce harmful emissions of mercury was adopted Saturday by more than 140 nations, capping four years of difficult negotiations but stopping short of some of the tougher measures that proponents had envisioned. The new accord aims to cut mercury pollution from mining, utility plants and a host of products and industrial processes, by setting enforceable limits and encouraging shifts to alternatives in which mercury is not used, released or emitted. Mercury, known to be a poison for centuries, is natural element that cannot be created or destroyed. It is released into the air, water and land from small-scale artisanal gold mining, coal-powered plants, and from discarded electronic or consumer products such as electrical switches, thermostats and dental amalgam fillings. Mercury compound goes into batteries, paints and skin-lightening creams. Because it concentrates and accumulates in fish and goes up the food chain, mercury poses the greatest risk of nerve damage to pregnant women, women of child-bearing age and young children. The World Health Organization has said there are no safe limits for the consumption of mercury and its compounds, which can also cause brain and kidney damage, memory loss and language impairment. A decade ago, Switzerland and Norway began pushing for an international treaty to limit mercury emissions, a process that culminated in the adoption of an accord Saturday after an all-night session that capped a weeklong conference in Geneva and previous such sessions over the past four years. "It will help us to protect human health and the environment all over the world," Swiss environment ambassador Franz Perrez told a news conference. But the treaty only requires that nations with artisanal and small-scale gold mining operations, one of the biggest sources of mercury releases, draw up national plans within three years of the treaty entering force to reduce and â¿¿ if possible â¿¿ eliminate the use of mercury in such operations. Governments also approved exceptions for some uses such as large measuring devices for which there are no mercury-free alternatives; vaccines where mercury is used as a preservative; and products used in religious or traditional activities.