This week, U.N. officials sat down for the first of five negotiating sessions aimed at developing a global, legally binding mercury treaty that will address the emissions and use of mercury in products, wastes and international trade.
The negotiations are expected to result in a global agreement that will be signed in late 2013.
But, there's plenty that has to be settled before then.
After all, the single largest source of anthropogenic mercury emissions is power generation (particularly from coal-fired power plants), and as Noelle Selin, an assistant professor of engineering systems in MIT's Engineering Systems Division, with a joint appointment in atmospheric chemistry in the Department of Earth, Atmospheric and Planetary Sciences, points out in her informative Q&A with the MIT News Office, that means getting international consensus for the treaty won't be easy.
"I see two major intersecting challenges: addressing the global spread of mercury emissions from coal-fired power plants in the context of the increasing demand for energy, and dealing with local impacts of mercury contamination," Selin says in the article.
Over the past few decades, the U.S. Senate has been loath to ratify multilateral environmental treaties, and Selin believes mercury mandates are likely to be especially thorny among legislators because as it stands now, the U.S. does not domestically regulate mercury emissions from coal-fired power plants. There are domestic mercury regulations for municipal-waste combustion and medical-waste incineration, and some states have begun regulating mercury in certain products (mostly electronics). But, the EPA has yet to implement mercury emissions standards for power plants.
Even if an international mercury treaty is approved, it would be difficult to enforce, and methods of implementation are likely to be among the most contentious aspects of the negotiation. Still, this week marks the start of critically important dialogue and debate.
"The extensive mercury pollution is perhaps the greatest challenge that the world faces when it comes to risks with chemical substances," Sweden's Minister for the Environment Andreas Carlgren says in a press release.