The Minamata Convention on Mercury, which marks its sixth anniversary, is a significant global agreement aimed at safeguarding people and the environment from the harmful impacts of mercury exposure.
Minamata Convention
- The Minamata Convention on Mercury is a global treaty to protect human health and the environment from the adverse effects of mercury and its compounds.
- It was agreed at the fifth session of the Intergovernmental Negotiating Committee in Geneva, Switzerland 2013. It entered into force in 2017.
- Controlling the anthropogenic releases of mercury throughout its lifecycle is one of the key obligations under the Convention.
- The Convention also addresses interim storage of mercury and its disposal once it becomes waste, sites contaminated by mercury as well as health issues.
- India has ratified the Convention.
Mercury Pollution
- Mercury is a naturally occurring element found in the Earth’s crust. It is considered by the World Health Organization (WHO) as one of the top ten chemicals or groups of chemicals of major public health concern.
Major Applications of Mercury
Thermometers and Barometers
- Mercury’s high coefficient of thermal expansion and easy visibility make it suitable for use in traditional thermometers and barometers.
Chemical and Mining Processes
- Mercury has been used in various chemical and mining processes, including the production of chlorine and mining of gold.
Electronics and Electrical Switches
- Mercury-wetted switches are used in various electrical applications because mercury’s conductivity and low resistance make it suitable for creating a reliable electrical connection.
Sources of Mercury Pollution
Natural Sources
- Volcanic eruptions release small amounts of mercury.
- Erosion of rocks and soil can release mercury into water bodies.
Anthropogenic Sources
- Artisanal and Small-Scale Gold Mining (ASGM): ASGM is a major source of mercury pollution, where mercury is used to extract gold from ore.
- Mercury is used to extract gold particles from ores, creating amalgams that are later heated to evaporate the mercury, leaving behind gold.
- Artisanal gold mining operations are responsible for 37% of global mercury pollution.
Industrial Processes
- Various industries, such as chlorine production, cement manufacturing, and waste incineration, emit mercury.
- The cement industry is responsible for around 11% of global anthropogenic mercury emissions.
Waste Disposal
- Improper disposal of e-waste products containing mercury, such as fluorescent bulbs and batteries, leads to mercury leaching into the environment.
Associated Impact
- Methylmercury accumulates in aquatic organisms like fish. People primarily come into contact with methylmercury through the consumption of fish and shellfish.
- This compound carries a higher risk of causing Minamata disease, a condition characterized by sensory impairment, tremors, and both auditory and visual deficits.