October 2013, the United Nations opened the Minamata Convention on Mercury for signature at a Conference of Plenipotentiaries (Diplomatic Conference) in Kumamoto, Japan. While not as strong as it should be, the new mercury treaty recognizes that exposure to mercury is a serious threat to human health and the environment. Among other things, it aims to lead the phase-out of mercury in some products and processes, and bans primary mercury mining. As of today, 92 countries have signed the Minamata Convention on Mercury. The United States is not among them.
Mercury, a natural occurring element, is also an extremely toxic environmental pollutant. For instance, when mercury enters the aquatic environment, certain bacteria can convert it into methylmercury, an organic compound that is more toxic than elemental mercury. Methylmercury bioaccumulates in fish and other aquatic organisms, and biomagnifies as it makes its way up the food chain. As a result, larger fish accumulate the methylmercury from smaller fish. Humans are vulnerable to methylmercury poisoning because we are at the top of the food chain. Eating fish is the most common way humans are exposed to methylmercury. The unborn are particularly vulnerable to methylmercury poisoning because the mother can pass her mercury load on to her fetus. It is known that methylmercury is detrimental to the developmental brain.
Minamata disease gets its name from a small village in southern Japan that witnessed the worst incident of methylmercury poisoning in history. For over two decades, a chemical company discharged its industrial mercury-containing wastewater into Minamata Bay, contaminating the bay’s fish and seafood with methylmercury. The methylmercury targeted the central nervous system of those who ate the Bay’s polluted fish and caused numbness of the limbs, loss of bodily movement and even death. Minamata disease’s legacy continues.
I had the opportunity to visit Minamata and Kumamoto to attend the preparatory meetings for the Diplomatic Conference, as well as several events organized by the International POPs Elimination Network (IPEN), a global network of more than 700 organizations from over 116 countries that work on environmental and public health issues. As part of my work with Alaska Community Action on Toxics (ACAT), I met Minamata disease victims and heard about their everyday struggle with the disease. Above all, I learned that they do not want any more outbreaks of Minamata disease around the world. I also learned about the work that other “IPENers” are doing in their respective countries to eliminate mercury emissions and exposure — from helping artisanal, small-scale gold miners in Indonesia and Tanzania to find mercury-free methods for gold extraction to educating people in Sri Lanka about the harmful health effects of mercury-containing skin-lightening creams.
I hope that the world’s governments will learn from the lessons of Minamata and ensure prompt and effective ratification of the Minamata Convention on Mercury. Citizens and experts that follow this issue closely have remarked that an effective mercury treaty should help resolve pending Minamata disease’s claims and ensure clean-up of contaminated areas of Minamata. Additionally, it would set-up timelines and dates for the phase out of mercury use from small-scale artisanal gold mining throughout the world. Without doubt, the Minamata disease victims and non-governmental organizations continue to have a lead role in helping to fulfill the treaty’s goals.