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Power stations threaten people and wildlife with mercury poisoning

February 04, 2003

Nairobi, 3 February 2003 - Mercury poisoning of the planet could be significantly reduced by curbing pollution from power stations, a new report released by the United Nations Environment Programme (UNEP) suggests.

The report, compiled by an international team of experts, says that coal-fired power stations and waste incinerators now account for around 1,500 tons or 70 percent of new, quantified man-made mercury emissions to the atmosphere. The lion's share is now coming from developing countries with emissions from Asia, at 860 tons, the highest.

"As combustion of fossil fuels is increasing in order to meet the growing energy demands of both developing and developed nations, mercury emissions can be expected to increase accordingly in the absence of the deployment of control technologies or the use of alternative energy sources," says the report.

Artisinal mining of gold and silver, which is happening in an increasing number of less developed nations, is another significant source of mercury pollution, releasing an estimated 400-500 tons of mercury annually to the air, soils, and waterways.

Mercury is used to extract these precious metals from ores, resulting in elevated exposures and risks for the miners and their families, as well as contamination of the local and regional environment.

Once in the atmosphere, this hazardous heavy metal can travel hundreds and thousands of miles, contaminating places far away from the world's sites where the pollution was originally discharged.

Reducing other pollution from power stations may also reduce the threats from mercury to humans and wildlife in indirect but equally important ways.

Temperature can also influence releases of mercury from contaminated sediments and soils into rivers, lakes and other freshwaters, the report suggests.

Here it can convert to methylmercury, one of it's most poisonous and hazardous forms, and build up in fish and other aquatic life forms with potentially harmful impacts on adults and infants. Numerous studies have linked brain damage in babies to mercury poisoning of their mothers as a result of eating contaminated fish.

Fish is still a beneficial food, and low to moderate consumption is considered safe and a healthy dietary practice. However, people who eat higher amounts of contaminated fish or marine mammals such as seals, may be at risk of mercury poisoning.

Most people are primarily exposed to methylmercury through eating contaminated fish. However, additional mercury exposures can occur through dental amalgams and certain occupational activities. Also, personal use of skin lightening creams and soaps, mercury use for religious, cultural and ritualistic purposes, use in some traditional medicines, use of vaccines and some other pharmaceuticals containing mercury preservatives (such as Thimerosal/Thiomersal) and mercury in the home and working environment can contribute to elevated exposures.

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

Just three years ago, the United States Research Council estimated that about 60,000 babies born each year in the U.S. could be at risk of brain damage with possible impacts ranging from learning difficulties to impaired nervous systems. However, based on more recent exposure data published by the US Centers for Disease Control and Prevention, some scientists think the number of at risk babies could be as high as 300,000. Globally the number could run into the millions.

Klaus Toepfer, UNEP's Executive Director, said: "Mercury is a substance that can be transported in the atmosphere and in the oceans around the globe, travelling hundreds and thousands of miles from where it is emitted. It has long been recognised as a health hazardous substance".

For example the Mad Hatter, of Alice in Wonderland fame, was so called because hatters used mercury to strengthen hats and were once exposed to high levels of mercury vapours.

"This new report, requested from UNEP by governments two years ago, shows that the global environmental threat to humans and wildlife has not receded despite reductions in mercury discharges, particularly in developed countries. Indeed it shows that the problems remain and appear, in some situations to be worsening as demand for energy, the largest source of human-made mercury emissions, climbs," he said.

"There are many compelling scientific, environmental and health arguments for curbing pollution linked with energy production. The mercury report gives us another compelling reason to reduce society's dependence on carbon intensive energy supplies," added Mr Toepfer.

Acid rain, again often the result of power station pollution, may be aggravating the problem.

High levels of acidity in rivers, lakes and streams, also appears to trigger releases of mercury from soils and sediments and its conversion into methylmercury.

The findings may explain why so many fish in parts of the world where acid rain has been an issue are contaminated. For example in southern and central Finland, an estimated 85 per cent of pike weighing a kilo or more, have methylmercury concentrations that exceed international health limits.

Other important sources of mercury releases include cement production, chlor-alkali production, crematories, manufacture of electrical switches, thermometers, fluorescent lamps, dental amalgams and rubbish tips containing wastes such as old batteries and other mercury-containing products.

Slash and burn agriculture and the clearing of forests may be increasing releases of mercury to rivers. Meanwhile, mercury contamination in parts of Europe may be affecting the tiny organisms that regulate the fertility of soils, says the study.

This may also be having an indirect effect on climate change as soil microorganisms play a key role in the storage of carbon from the atmosphere.

These are some of the findings to emerge from the global study of mercury carried out by experts for UNEP. The report is being presented to environment ministers from across the world who are attending UNEP's Governing Council, and will form the basis for political decisions that will set the course for global action on mercury for years to come. The Council is meeting at the organization's headquarters in Nairobi, Kenya, from 3 to 7 February 2003.

The findings also come in advance of World Water Day, which happens on 22 March and is being organized by UNEP. It will be celebrated at the World Water Forum taking place in Kyoto, Japan.

Here the findings will have special significance. Several thousand people were made ill or died in Japan in the 1950 and 60s as a result of eating seafood heavily contaminated by mercury in Minamata Bay.

The experts who have compiled the report are asking governments attending the GC to consider a list of options for addressing the dangers of mercury. These include reducing risks by reducing or eliminating the production, use and release of mercury; substituting other non-mercury based products and processes; launching talks for a legally-binding treaty; establishing a non-binding global programme of action; and strengthening cooperation amongst governments on information-sharing, risk communication, assessment and related activities. They also recommend around a dozen "immediate actions" including public awareness programmes targeted at sensitive populations such as pregnant women; waste disposal facilities for the safe destruction of obsolete, mercury-containing pesticides and pollution control technologies for power stations.

United Nations Environment Programme