Mercury is a highly toxic heavy metal (WHO, 2007), posing a threat particularly the development of the child in utero and in their early years. It occurs naturally and exists in various forms: elemental (or metallic); inorganic (e.g. mercuric chloride); and organic (e.g., methyl- and ethyl mercury). All these forms have different toxicities and implications for health and for measures to prevent exposure. Elemental mercury is a liquid that vaporizes readily. It can stay for up to a year in the atmosphere, where it can be transported and deposited globally. It ultimately settles in the sediments of lakes, rivers or bays where it is either transformed into methyl mercury, absorbed by phytoplankton, ingested by zooplankton and fish, and accumulates especially in long-lived predatory species, such as sharks and swordfish.
Although the toxicity of mercury is known for years, its unique physio-chemical properties have led to its use in several products and industrial/manufacturing process. Mercury is still widely used in its various forms in consumer products and processes across the globe. Medical equipment such as thermometers and sphygmomanometers, dental fillings, electric lamps and switches, electronic items, and industrial process such as in the chlor-alkali sector, pesticides and drugs, cosmetics etc. are just to name a few using mercury.
However, in the recent decades there has been global drive to phase-out mercury from most of the sectors. Even emissions from thermal plants are also been part of the global negotiations. Both for upstream and downstream mercury management, there are proven technologies for phasing out mercury.
Toxics Link is campaigning for the phase-out of mercury since over a decade. Mercury use in health care sector and in the lighting sector has been the major focus of this campaign. In these years there has been a lot of baseline information creation for almost all the sectors using mercury in India. There were also a few studies on mercury contamination in all environmental media and food (see publication sub-section). In all the negotiations at the national and international levels, Toxics Link has been identified as a key stakeholder and made critical interventions and contributions.
Interventions in the health care sector have been separately covered under the sub-section ‘mercury in health care’.