A new treaty to control mercury…could be good for climate too

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courtesy: UNEP

Early in the morning on Saturday, January 19, 2013, negotiators from around 140 countries completed negotiations for the Mercury Treaty that will be adopted later this year in Japan. It will be known as the Minamata Convention, in deference to the victims of mercury poisoning from industrial pollution that occurred when residents of the Minamata Bay ingested contaminated fish and shellfish in the 1950s.

The Convention that took four years to negotiate under the auspices of the United Nations Environment Programme (UNEP) joins the ranks of a number of treaties that address chemicals and wastes. It is the first treaty to specifically address heavy metals.

Why is the international community concerned about mercury? Mercury is typically released into the environment in metallic, or “elemental”, form, or as an inorganic salt. In elemental form, it easily vaporises and can be transported great distances worldwide.  When deposited in the environment, mercury eventually can be transformed to its organic forms, including Methylmercury, which is highly toxic and readily accumulates and bioconcentrates in animals and humans. Eventually, mercury settles in cold climates and bioconcentrates up the food chains to the point that Indigenous Peoples in the North that rely on traditional foods are exposed to damaging high levels.

One of the reasons heavy metals are difficult to address is that they are mobilised through human activities, but they are also released in the environment through natural processes, for example through volcanic eruptions or in deep-sea vents. Nevertheless, estimates are that at any given time, 90% of the mercury cycling in the environment is linked to human activities – hence the need for action. The recently released UNEP Global Mercury Assessment 2013 outlines major sources of emissions, geographic and temporal trends, and behaviour in the environment. 

Moreover, international action is warranted because of the transboundary dimension of the issue. In the United States for example, it is estimated that half the mercury in fish caught in rivers comes from anthropogenic Continental sources – predominantly from coal burning – whilst the other half represents emissions from Asia. At the same time, by some estimates, approximately 50% of US releases are deposited beyond the country’s border. This is textbook justification for international action.

The new treaty bears some similarities with others such as the Stockholm Convention on Persistent Organic Pollutants, but it also takes into account some of the lessons learned from these existing treaties.

Actions taken under the Convention could provide climate benefits. The Convention will work towards reducing emissions in the atmosphere and releases to water and land by, among other things: requiring that industrial sources that are known to emit mercury such as coal-fired power plants, industrial boilers, smelting, cement kilns, and waste incineration, apply best available techniques; phasing out certain industrial processes that use and release mercury such as mercury-based chloralkali production; requiring each country with significant artisanal and small scale gold mining develop an action plan with reduction targets to manage mercury use downwards; phasing out and phasing down the use of mercury in products (e.g. thermometers and compact fluorescent lamps); and generally controlling supply and trade of mercury.

The Convention includes an Implementation and Compliance Committee meant to facilitate implementation. Such a compliance mechanism is often cited to explain the success of the Montreal Protocol. The treaty also establishes a financial mechanism, including the Global Environment Facility (GEF), to support developing countries in meeting the incremental costs of measures that bring global environmental benefits.

The Convention will be open for signature in October 2013, and will enter into force when it is ratified by at least 50 countries, which should take over two years after signature. Overall, there were large differences of views on the scope and approaches for the treaty at the onset of the final week of negotiations. As a result, a number of issues have been left to be further developed and defined by the Parties. Some environmental NGOs have regretted that the Treaty lacked “teeth” in many respects and would not achieve the necessary environmental reduction, as always what will matter most is how the treaty is implemented.

The framework that was agreed is comprehensive and does offer potential for real on-the-ground reductions as the Convention is implemented, provided technical and financial assistance is transferred to developing countries as envisaged.



Laurent Granier

Senior Environmental Specialist

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