In India where a large percentage of the population eat fish as a staple food, no provisions for daily or weekly mercury intake levels have been set down.
Bush's regime in the US was one of a handful of countries that blocked efforts in establishing a global legally binding instrument to control and phase-out mercury. Public interest groups are hopeful, that with a new administration, a new policy will be adopted by the US.
Before becoming president, Obama sponsored the bill that banned export of these toxins from the US therefore, there is an optimistic that he will pave the way for a successful a global campaign that would lead to the phase-out in the use and trade of mercury. It is high time there is change in the global policy on mercury.
Mercury is a dangerous neurotoxin that can make its way up the food chain into humans, and poses an increased exposure risk to developing fetuses and young children, causing permanent learning disabilities. Mercury is a persistent, bioaccumulative transboundary pollutant. Emissions from other countries travel to the U.S., contaminating our air, soil, water and fish. Because of this potential for global contamination, mercury pollution requires a coordinated international response.
Of high concern are mercury emissions from coal-fired power plants, and indeed these are important sources of mercury pollution in our country and throughout the world. Mercury is also a commodity metal (like iron or copper), traded on the global market, and is used, both here and abroad, for many industrial and commercial purposes.
As a result, the continued trade in mercury also contributes to global mercury pollution. Because of its toxic nature and increasingly available alternatives to its use, there is an unique opportunity and responsibility to address this contaminate through international regulation or ban of its trade.
Since 2001, countries around the world have been discussing options to control mercury pollution and in 2003 agreed that enough was know to warrant immediate action to reduce global mercury pollution. Most countries now favor the negotiation of a legally binding international agreement as the most viable approach to deal with this problem. However, over the past six years, the Bush administration consistently opposed this position.
In mid-February, the world will take up this question again at the 25th meeting of the United Nations Environment Programme Governing Council. At this meeting, the United States must change its current position on mercury and come prepared to support a legally binding agreement to reduce mercury exposure.
The UNEP Governing Council meeting will provide the new US administration with its first opportunity on the world stage to demonstrate a real change in approach to international environmental issues, an approach that embraces cooperation and leadership, rather than obstruction and inaction.
In order to integrate food laws, many of them item specific that were dealt with by different agencies, the Food Safety and Standards Act has been conceived in India as an integrated food law that is to be administered by a single autonomous and scientific regulatory body but this does not seem to deal with mercury.
The Prevention of Food Adulteration Act declares mercury as a poisonous metal and limit its concentration in fish to 0.5 ppm and in other food items to 1.0 ppm. Methyl mercury is one of the more dangerous forms, and its concentration in fish is limited to 0.25 ppm.
The Bureau of Indian Standards has laid down safety limits for drinking water at 0.001 mg of mercury per litre. The WHO and the Food and Agriculture Organisation have specified limits on the concentration of methyl mercury for fishes.
Mercury is a potent neurotoxin. Even at extremely low levels of exposure, it can cause permanent damage to the human central nervous system. The 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.
At higher levels, mercury can damage vital organs such as lungs and kidneys. Common exposures are through food and the diet; with exposure also occurring through air and water.
The symptoms of methyl mercury poisoning are varied and can mimic other illnesses. Many of the symptoms take a number of weeks, or even months, to appear. The symptoms include tingling and numbness of extremities; depression, emotional instability, memory reduction, irritability; defects in hearing, vision and speech;difficulty in writing, delays in motor and language development, inability to walk properly, tremors, and in extreme cases, death.
International Chemical Safety Council of United Nations rates methyl mercury – an organic form of mercury – as one of the six most serious pollution threats to the planet. Methyl mercury intake through fish and other aquatic foods has a considerable effect on human health. Some surveys that provide information on the percentage of mercury originating from fish assume that the percentage of methyl mercury ranges from 60 to 90 per cent. This implies that fish and fish products that we eat can be a major source of methyl mercury.
Unborn foetuses are particularly at a high risk from methyl mercury poisoning. Methyl mercury can cross the placental barrier and cause foetal brain damage without any symptoms in the expectant mother.
The situation is India not a happy one. The first global study on mercury has said recently that India could be one of the dozen hot spots after the rise in mercury emissions over 30 years”. The UNEP Governing Council has said that there is sufficient evidence of significant global adverse impacts to warrant international action aimed at reducing the risks to human health and the environment, which arise from the release of mercury into the environment.
The largest consumer of mercury in India is the chlor-alkali industry, which manufactures caustic soda and chlorine as a by-product using the mercury cell process. The second-largest consumption of mercury in India is for the production of measuring instruments such as thermometers, barometers, etc. It is also used in manufacturing electrical apparatus, mercury vapour lamps, electrical switches, fluorescent lamps, etc.
Recent studies have shown that the total mercury pollution potential from coal in India is estimated to be 77.91 tonnes per annum, if average concentration of mercury in coal is assumed to be 0.272 ppm. About 59.29 tonnes of mercury per annum is mobilised from coalfired thermal power plants alone.11 The five super thermal power plants in the Singrauli area, which supply 10 per cent of India’s power, are responsible for 16.85 per cent or 10 tonnes per annum of total mercury pollution through power generation.
Some of the major rivers tested for heavy metals by the Industrial Toxicological Research Centre (ITRC), Lucknow, were found to contain mercury in alarming levels. Testing of seawater by the National Institute of Oceanography, Goa, found increased mercury concentrations in the Arabian Sea. Several studies on fish and prawns in Mumbai, Kolkata, Orissa, etc, have reported alarming rates of mercury concentrations.
A study conducted by the Environmental Science Department of the Guru Gobind Singh Indraprastha University, Delhi, had revealed that the concentration of contaminants like arsenic, mercury, nitrates, etc, in the groundwater of Delhi exceeds the permissible limits. The study entailed 50 samples of groundwater being lifted from random spots along a 22-km stretch between Palla and Okhla. The mercury concentration in some samples was as high as 4.6 ppm, 460 per cent above the permissible limit. This alarming presence of mercury in groundwater can be traced to the continuous discharge of sewage and industrial effluents into the Yamuna and, subsequently, into the groundwater aquifer which, being sandy in nature, allows mercury pollution to spread at a rapid rate.
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