September 27, 2013 report
Minamata convention treaty seeks to reduce mercury pollution
Global warming has filled the headlines for years, outshined in the press but still as ominous, however, is the growing problem of mercury pollution. Like global warming, it's not an easy problem to solve and likely won't be for decades, if not centuries. This is because once mercury gets into the environment it can take hundreds of years to make its way to non-harmful places, such as silt in the bottom of the ocean.
Over the past couple of centuries, mercury has made its way into the environment primarily due to burning coal to make electricity. Most of that mercury is still here with us—once in the atmosphere it is brought down to land when it rains making its way into the soil. Fires can cause it to move back into the atmosphere and floods or heavy watering can cause it to travel through the water table into streams, rivers, lakes and the oceans, some of which makes it back into the atmosphere through evaporation. Fortunately, scientists have realized the dangers posed by mercury (birth defects, brain disorders, etc.) and the result has been a major decrease in the amounts of mercury emitted by coal firing plants and other sources. Sadly, as Wade describes, such sources have recently been replaced by individuals using mercury as an aid to small operation gold and silver mining. They are now the single largest source of mercury polluters, and little is being done to stop them. Most such miners are poor and rely on the small amounts of precious metals they are able to extract from mud in remote places such as villages in Peru or parts of Asia.
The treaty being signed in Minamata aims to curb such practices, but is largely symbolic. For now, the only way to stop the practice appears to be offering miners a better alternative, and thus far, it seems no one has come up with one.
More than 140 nations recently agreed to a legally binding treaty on reductions in human uses and releases of mercury that will be signed in October of this year. This follows the 2011 rule in the United States that for the first time regulates mercury emissions from electricity-generating utilities. Several decades of scientific research preceded these important regulations. However, the impacts of global change on environmental mercury concentrations and human exposures remain a major uncertainty affecting the potential effectiveness of regulatory activities.
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