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Adoption of UN Minamata Convention on Mercury is a welcome step

Written By Gopal Krishna on Friday, October 11, 2013 | 5:52 AM

1/70th of a teaspoon of Mercury makes fish of 25-acre lake unfit for consumption

Mercury is one of the top ten chemicals of major public health concern

Declaration of Minamata like disaster awaits India

Maximum contaminant level for mercury in drinking water is .000002 g/L

October 11, 2013:ToxicsWatch Alliance (TWA) welcomes the adoption of UN's Minamata Convention on Mercury to protect human health and the environment from anthropogenic emissions and releases of mercury and mercury compounds. Mercury is a persistent pollutant.

It persistence can gauged from the fact that addition of even 0.9 grams of mercury, that is,
one minuscule fraction (1/70th) of a teaspoon is enough to contaminate a 25-acre lake,
rendering fish contaminated and unsafe to eat. The maximum contaminant level for mercury in drinking water is 2μg/L ( .000002 g/L). [1 g = 1,000,000 μg]

It is noteworthy that just one drop of mercury can poison enough water to fill 10 big tanker trucks which has 89,000 gallons of water. (1 gallon = 3.8 liters)

Exposure to mercury – even small amounts – may cause serious health problems, and is a threat to the development of the child in utero and early in life.

The treaty gets its name from Minamata a city in Japan where Chisso Corporation opened a chemical factory in 1908. The chemical reaction used to produce the acetaldehyde used mercury sulfate as a catalyst. A side reaction of the catalytic cycle led to the production of a small amount of an organic mercury compound, namely methylmercury. This highly toxic compound was released into Minamata Bay from the start of production in 1932 until 1968, when this production method was discontinued. Local public health office in the city discovered an "epidemic of an unknown disease of the central nervous system" in 1956. The city government formed the Strange Disease Countermeasures Committee. The disease later became known as Minamata disease. From around 1950 onward, cats had been seen to have convulsions, go mad and die. Crows had fallen from the sky, seaweed no longer grew on the sea bed and fish floated dead on the surface of the sea. On November 12, 1959, the Ministry of Health and Welfare's Minamata Food Poisoning Subcommittee published its results sating "Minamata disease is a poisoning disease that affects mainly the central nervous system and is caused by the consumption of large quantities of fish and shellfish living in Minamata Bay and its surroundings, the major causative agent being some sort of organic mercury compound."

The medical belief that the placenta protects the foetus from toxins in the bloodstream, which is indeed the case with most chemicals was given a burial. In the case of  methylmercury, the placenta removes it from the mother's bloodstream and concentrates the chemical in the foetus. Thus, the disease manifested its congenital form.

Mercury has toxic effects on the nervous, digestive and immune systems, and on lungs, kidneys, skin and eyes. Mercury is considered by WHO as one of the top ten chemicals or groups of chemicals of major public health concern. People are mainly exposed to methylmercury, an organic compound, when they eat fish and shellfish that contain the compound.

In India, High levels of mercury in fish stocks have been found, mainly in coastal areas. Mumbai, Kolkata, Karwar, in Karnataka and North Koel, in Bihar are some of the severely affected areas. In Mumbai, mercury levels in fish were 0.03-0.82 mg total Hg/kg dry weight (dw); crabs had 1.42-4.94 mg total Hg/kg dw mercury compared to the permissible limit of 0.5 mg/kg.Mercury levels in oysters in Karwar ranged from 0.18-0.54 mg/kg dw.The North Koel river showed mercury concentrations almost 600-700 times above the limits.

Mercury in ground water and surface water has been detected from across the country in cities like Delhi, Mumbai, Vadodara, Vapi, Ankleshwar, Bhopal, Panipat, Singhrauli, Ganjam, Dhanbad, Durgapur, Howrah, Medak and numerous other cities.

This global treaty is hardly enough for India where impunity rules the roost even when levels are found higher than the permissible limits near chlor-alkali, cement and chemical units and thermal power plants.

Anthropogenic releases of mercury to water total 1000 tonnes at a minimum. Artisanal and small-scale gold mining and coal burning are the major sources of anthropogenic mercury emissions to air. This accounts for more than 35% of total anthropogenic emissions.

Notably, total anthropogenic emissions of mercury to the atmosphere in 2010 are estimated at 1960 tonnes (1 tonne = 1000 kilograms). This is the estimate when use of mercury in vinyl-chloride monomer production; secondary metals production and ferro-alloys; oil and gas extraction and transport; and industrial and some hazardous waste incineration is yet to be included. Coal burning emitted some 475 tonnes of mercury in 2010, the majority of which is from power generation and industrial use.

In the absence of estimates for 2013 it can safely be understood that with unmet regulatory challenges this emission must have increased quite a lot since then.

The 44 page report "Global Mercury Assessment 2013: Sources, emissions, releases, and environmental transport" had underlined the anthropogenic emissions of Mercury to air and the aquatic environment. The report provides the most recent information available on worldwide atmospheric mercury emissions, releases to the aquatic environment, and the transport and fate of mercury in the global environment. It emphasizes emissions to air from human (anthropogenic) activities, but includes releases to water because the aquatic environment is the main route of exposure to humans and wildlife. It is in aquatic systems that the inorganic mercury is transformed into the more toxic form, methylmercury, which can accumulate in fish and marine mammals consumed by humans.

This report states that "Asia contributes almost half of global anthropogenic mercury emissions". It does not seen to factor in the contribution of European and other developed countries for some 200 years since the inception of modern industrial age.  Global inventories for mercury emissions to air from human sources have been produced at approximately 5-year intervals since 1990 by scientific groups UNEP produced its first Global Mercury Assessment in 2002.

Even now blind industrialization by non-Asian and Asian countries by externalizing human and environmental health cost since the beginning of the modern industrial age is yet to be internalized.

Given teh fact that elemental and methylmercury are toxic to the central and peripheral nervous systems, inhalation of mercury vapour can produce harmful effects on the nervous, digestive and immune systems, lungs and kidneys, and may be fatal. The inorganic salts of mercury are corrosive to the skin, eyes and gastrointestinal tract, and may induce kidney toxicity if ingested.

Neurological and behavioural disorders may be observed after inhalation, ingestion or dermal exposure of different mercury compounds. Symptoms include tremors, insomnia, memory loss, neuromuscular effects, headaches and cognitive and motor dysfunction. Mild, subclinical signs of central nervous system toxicity can be seen in workers exposed to an elemental mercury level in the air of 20 μg/m3 or more for several years. Kidney effects have been reported, ranging from increased protein in the urine to kidney failure.

There are several ways to prevent adverse health effects, including promoting clean energy, stopping the use of mercury in gold mining, eliminating the mining of mercury and phasing out non-essential mercury-containing products.

This creates a compelling logic for promotion of the use of clean energy sources that do not burn coal. Coal contains mercury and other hazardous air pollutants that are emitted when the coal is burned in coal-fired power plants, industrial boilers and household stoves.
There is a need to eliminate mercury mining, and use of mercury in gold extraction and other industrial processes.

It is noteworthy that Mercury is an element that cannot be destroyed; therefore, mercury already in use can be recycled for other essential uses, with no further need for mercury mining. Mercury use in artisanal and small-scale gold mining is particularly hazardous, and health effects on vulnerable populations are significant. Non-mercury (non-cyanide) gold-extraction techniques need to be promoted and implemented, and where mercury is still used safer work practices need to be employed to prevent exposure.

Government of India should initiate a program to phase out use of non-essential mercury-containing products and implement safe handling, use and disposal of remaining mercury-containing products. Mercury is contained in many products, including batteries, measuring devices, such as thermometers and barometers, electric switches and relays in equipment, lamps (including some types of light bulbs), dental amalgam (for dental fillings), skin-lightening products and other cosmetics and pharmaceuticals.

The World Health Organization has been providing guidance on identifying populations at risk from mercury exposure, tools to reduce mercury exposure, and guidance on the replacement of mercury-containing thermometers and blood pressure measuring devices in health care.

It is promoting the sound management and disposal of health-care waste and has facilitated the development of an affordable, validated, non-mercury-containing blood pressure measuring device.

The UN treaty opened for signature by countries on 10 October 2013, at a Diplomatic Conference in Kumamoto, Japan. As of October 11, 2013 there are 91signatories to the Convention. The Convention will enter into force 90 days after it has been ratified by 50 nations.  The draft convention text was concluded on January 19,  2013 with 147 governments agreeing to it.

The continued release of mercury into the environment from human activity, the presence of mercury in the food chain, and the demonstrated adverse effects on humans made the governments to agree to the Minamata Convention on Mercury. The Convention obliges government Parties to take a range of actions, including to address mercury emissions to air and to phase-out certain mercury-containing products.

Some 2,265 victims have been officially certified of Minamata disease of which some 1,784 of have died and over 10,000 people have received financial compensation till 2001 from Chisso Corporation in Japan.

Regulatory agencies in India have failed to protect the food chain from the criminal poisoning by such corporations and seem to waiting for a formal announcement of Minamata like disaster to react.

Will Government of India awake from it slumber in the face of alarming level of mercury contamination especially due to the discharge of mercury-bearing industrial effluents ranging from 0.058 to 0.268 milligram/litre (mg/l) which is several times more than the prescribed Indian and WHO standards of 0.001 mg/l for drinking water and 0.01 mg/l for industrial effluents?.

A teaspoon of mercury and a teaspoon of water are of the same volume but not the same weight. Density of Mercury is 13.534 g/cm3. There is about 20 drops per cm3. It is not realized as yet that just 1 teaspoon of mercury can poison all the water a family of 4 would use in 63 years.

For Details: Gopal Krishna, ToxicsWatch Alliance, Mb: 9818089660, E-mail:gopalkrishna1715@gmail.com Web: www.toxicswatch.org
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