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Action on the global mercury pollution

2009/1/14

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 Some 60 years after the tragic Minimata poisoning hit the headlines, international action on global mercury pollution is again rising on the global thermometer.

 Next month governments will meet for UNEP’s Governing Council/Global Ministerial Environment Forum with an international response to this notorious heavy metal high on the agenda.

 It comes amid concern that, far from declining, levels of mercury pollution may be on the rise with at least some of the emissions linked with increased coal-burning and demand for gold.

 There are also growing worries about the impacts of climate change on mercury locked away in northern lake sediments and sensitive regions such as the Arctic.

 Rising temperatures linked with climbing greenhouse gases may be triggering releases of mercury and its highly toxic compound-methyl mercury-as waters warm and ice recedes.

 Emitted to the atmosphere or re-released into oceans, lakes and river systems this pollutant can travel hundreds and thousands of miles, entering the food chain via for example fish and then to the dinner tables of consumers across the world.

 Eating advisories relating to fish consumption remain in place in many countries targeted at those at risk including pregnant mothers and babies.

 In Sweden, for example around 50,000 lakes have pike with mercury levels exceeding international health limits. Women of child-bearing years are advised not to eat pike, perch, burbot and eel at all, and the rest of the population only once a week.

 This is because mercury and methyl mercury can cause neurological damage in young and developing brains.

A study of women in the United States has found that about 1 in 12, or just under five million females, have mercury levels above the level considered safe by the US Environmental Protection Agency.

Between 60,000 and 300,000 babies born in the United States could be at risk and globally the number could run into many millions.

 Other potential impacts on young and old alike include impaired thyroid and liver function, irritability, tremors, disturbances to vision and memory loss. There is recent scientific evidence linking mercury exposure to cardiovascular problems.

 Scientists and the NGO Sharkproject are also flagging yet another cause for concern--;the increased consumption of shark meat in some parts of the world. By some estimates these foods contain up to 40 times more mercury than recommended food safety limits and perhaps a great deal more.

Mercury levels in Arctic ringed seals and beluga whales have increased by up to four times over the last 25 years in some areas of Canada and Greenland. This has implications for wildlife but also human health where marine mammals form a significant part of the diet.

 Next month’s meeting--;being held at UNEP’s global headquarters in Nairobi, Kenya--;follows some seven years of intense debate about possible solutions to the global mercury challenge. This meeting provides an opportunity for decisions to be taken which will allow real, globally coordinated reductions in mercury emissions.

 The good news is that both Europe and the United States have in recent months backed export bans on mercury with the European Union setting a date of 2011.

 Meanwhile a wide-range of products and processes that once depended on mercury now have cost effective, well proven and safer alternatives.

 This includes thermometers, high-intensity discharge automobile lamps and the chlor-alkali chemical process.

 The case for others is perhaps less clear cut at least for some manufacturers and economies.

 High-intensity discharge lamps for use outside the automobile industry, some liquid crystal display units and certain kinds of plastics production in China spring to mind.

 Flexibility needs to be shown but also some sense of vision. Only by setting a clear and unequivocal landscape of a low mercury future will governments trigger innovation and an ever greater array of cost effective, alternative products and processes.

 Artisanal and small-scale gold mining is perhaps a special case. The victims are among the poorest people in the world producing a product that for all practical purposes has few if any direct industrial uses anymore.

 An estimated 10 million miners and their families may be suffering in fields ranging from Brazil and Venezuela to India, Indonesia, Papua New Guinea and Zimbabwe.

 A case in point is in a gold-mining area near Mount Diwata on the island of Mindanao in the Philippines. Studies indicate that 70 per cent of workers were found to be suffering chronic mercury intoxication.

 For those workers involved directly in smelting using mercury, the percentage was even higher at 85 per cent.

 Around one third of people not directly employed in the industry, but living in the area, also showed signs of chronic mercury intoxication.

 The alternative to mercury in small-scale mining is really no alternative at all--;it is cyanide. Thus alternative livelihoods must be found and quickly.

 I have written recently about UNEP’s Green Economy initiative and will no doubt write about it again. Mercury is certainly part of that debate.

 Of the around 6,000 tonnes of mercury entering the environment annually, some 2,000 tonnes comes from coal-burning in power stations and homes.

 Thus combating climate change by reducing fossil fuel use by energy efficiency improvements and a greater deployment of renewables will not only deal with global warming, but also cut mercury pollution too.

 And in curbing climate change we can also reduce re-releases of trapped mercury from, for example the Arctic.

 The wider economic arguments also stack up. UNEP estimates that every kilogramme of mercury taken out of the environment can trigger up to $12,500 worth of social, environmental and human health benefits.

 The people living in and around Minamata Bay who suffered such appalling, chronic mercury contamination in the middle of the 20th century know the true horrors of heavy metal poisoning.

 The deformities bear testament to not only the severity of the pollution but also the suffering as a result of years of denial about the true cause.

 The global population is currently and in general exposed to far lower exposure levels than those exposed in Kumamoto prefecture between 1932 and 1968, but exposed they are.

 No one alive today is free from some level of mercury contamination and the World Health Organization argues there is in the end no safe limit.

 Thus denial and inaction over the global mercury challenge are no longer an option either--;we owe it to pregnant women and unborn children North and South and to artisanal miners and their families. Perhaps above all we owe it to the survivors and to the memory of the victims of heavy metal pollution incidents world-wide during the past century.

Profile

Achim Steiner

Achim was born in Carazinho, Southern Brazil in 1961 of German parents. After recieving an MA from the University of London, specializing in development economics, he worked at several international environmental organizations. Before joining UNEP, he served as Director General of the World Conservation Union (IUCN, HQ in Switzerland) from 2001 to 2006. IUCN compiles the Red List of Threatened Species. He has served as the Executive Director of UNEP since June 2006. His hobbies are moviegoing and shopping in flea market. He is a father of two.

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