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نویسنده: حسین بدری پور - شنبه ٢۳ دی ۱۳٩۱

برنامه محیط زیست ملل متحد به تازگی در گزارشی به بررسی وضعیت مصرف جیوه و آثار آن بر محیط زیست و سلامت انسان ها پرداخته است. دبیر کل سازمان ملل متحد هم بر اساس این گزارش از کشورها خواسته است برای کنترل آلودگی ناشی از جیوه اقدامات عاجلی به کار بندند. برای دریافت گزارش یونپ با عنوان Mercury, time to act اینجا کلیک کنید.


NEW UN ENVIRONMENT  STUDIES SHOW RISING MERCURY THREAT TO PEOPLE IN DEVELOPING COUNTRIES New York, Jan 10 2013 11:00AM Communities in developing countries are facing increasing  health and environmental risks linked to exposure to mercury, according to new  studies by the United Nations environmental agency. 

Produced by the UN Environment Programme (UNEP), the studies  note how parts of Africa, Asia and South America  could see increasing emissions of mercury into the environment, due mainly to  the use of the toxic element in small-scale gold mining, and through the  burning of coal for electricity generation.

“Mercury, which exists in various forms, remains a major  global, regional and national challenge in terms of threats to human health and  the environment,” UNEP’s Executive Director, Achim Steiner, said in a <"http://www.unep.org/newscentre/Default.aspx?DocumentID=2702&ArticleID=9366&l=en">news  release on the studies.

Mercury – a naturally-occurring, silvery-white metal that is  liquid at ordinary temperatures – can be harmful to humans and the environment.  When released from industry and other man-made sources, it can circulate in the  environment for up to centuries at a time. This, according to UNEP, means that  it is likely to be several years or decades before reductions in mercury  emissions have a demonstrable effect on mercury levels in nature and the food  chain.

One of the UNEP studies, the <em>Global Mercury Assessment 2013</em> – which provides a comprehensive  breakdown of mercury emissions by region and economic sector – reports that  emissions of the toxic metal from artisanal gold mining have doubled since  2005, in part due to new and better information, but also due to rising gold  prices that are expected to lead to further increases

Due to rapid industrialization, it further notes, Asia is the largest regional emitter of mercury, and  accounts for just under half of all global releases.

The UNEP study also assesses, for the first time at a global  level, releases of mercury into rivers and lakes. Much human exposure to  mercury is through the consumption of contaminated fish, making aquatic  environments the critical link to human health. 

In the past 100 years, man-made emissions have caused the  amount of mercury in the top 100 metres of the world’s oceans to double.  Concentrations in deeper waters have increased by up to 25 per cent. 

The study highlights significant releases into the  environment linked to contaminated sites and deforestation, with an estimated  260 tonnes of mercury – previously held in soils – being released into rivers  and lakes.

Along with a parallel UNEP study, <em><"http://www.unep.org/PDF/PressReleases/Mercury_TimeToAct.pdf">Mercury: Time to Act</em>, the new assessment will be formally presented  at the International Negotiating Committee on Mercury, to be held in Geneva from 13 to 18  January this year.

According to UNEP, governments attending the conference are  aiming to conclude discussions on a global legally binding treaty to minimize  risks to people and the environment from exposure to mercury.<br>
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  The UN agency notes this would reduce cases of neurological  and behavioural disorders, and other health problems linked to mercury, as well  as the contamination of soils and rivers caused by man-made emissions of the  metal. 
  
Governments gave the green light to negotiations towards a  global treaty at the UNEP Governing Council held in Nairobi, Kenya,  some years ago. 

“In 2009, at the UNEP Governing Council, nations agreed to  launch negotiations for a legally binding treaty aimed at bringing down  releases from sources such as industry and mining, address mercury-containing  products, and tackle historical pollution sites—the final negotiations begin in  just a few days’ time,” said Mr. Steiner.

“Mercury has been known as a toxin and a hazard for  centuries – but today we have many of the alternative technologies and  processes needed to reduce the risks for tens of millions of people, including  pregnant mothers and their babies,” the UNEP chief added. “A good outcome can  also assist in a more sustainable future for generations to come.”

The UNEP studies state the fact that mercury released from  man-made sources can circulate for such a long time reinforces the need for  swift action by governments, industry and civil society to strengthen efforts  to reduce mercury emissions and releases. 

Delays in action, according to the reports, will lead to  slower recovery of ecosystems and a greater legacy of pollution.

Amongst other findings in the studies, UNEP highlights the rising  levels of mercury present in the Arctic, where  an estimated 200 tonnes of mercury are deposited each year, generally far from  where it originated. Studies have shown a ten-fold increase in levels of  mercury in certain Arctic wildlife species in the past 150 years, due mainly,  it is thought, to human activity.

The two UNEP studies state that global emissions of mercury  have remained relatively stable in the last 20 years, with 2010 emissions from  human activities thought to be just under 2,000 tonnes.

However, despite improved availability of data on mercury,  the emissions estimate is still subject to uncertainty, and covers a range of 1,010  to 4,070 tonnes.

Coal burning is responsible for some 475 tonnes of mercury  emissions annually, or around 24 per cent of the global total. UNEP notes that  despite increased coal combustion in certain regions, more stringent  regulations on pollution in several countries have contributed to reducing  overall mercury emissions from coal burning and off-setting part of the  emissions arising from increased industrial activity. 

Along with coal burning, the use of mercury to separate  metal from ore in small-scale gold mining remains the chief source of emissions  worldwide, according to UNEP. Annual emissions from small-scale gold mining are  estimated at 727 tonnes, or 35 per cent of the global total. 

Greater exposure to mercury poses a direct threat to the  health of some 10-15 million people who are directly involved in small-scale  gold mining, mainly in Africa, Asia and South America.  An estimated three million women and children work in the industry.

Mercury-free methods and other low-cost solutions for  reducing emissions during gold extraction are available, UNEP notes, but  socio-economic conditions, and low awareness of the risks of mercury, are  barriers to adopting safer techniques. 

حسین بدری پور
من بیش از یک دهه سابقه کار در سازمان جنگلها، مراتع و آبخیزداری کشور را دارم و در حال حاضر هم در مقطع دکترای منابع طبیعی تحصیل می نمایم. هدف از راه اندازی این وبلاگ اطلاع رسانی در خصوص مباحث روز منابع طبیعی و محیط زیست از قبیل همایش ها، پروژه ها و طرح های مرتبط در سطح ملی و بین المللی می باشد.
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