"This is only a preliminary calculation, and does not include the funds needed to treat the places contaminated by POPs," said Zhuang Guotai, deputy director of the office for Stockholm Convention Implementation under the State Environmental Protection Administration.

He said that the funds needed to treat the polluted areas "could be very huge" and difficult to estimate as there is still insufficient information about how many areas have been contaminated and how seriously they have been affected.

China has drafted a plan to phase out the world's most toxic chemicals as required by the Stockholm Convention on Persistent Organic Pollutants, he said.

According to the plan, China will stop the production and use of chlordane, mirex and DDT used in anti-dirt paint by 2010, and safely dispose of electric appliances containing POPs by 2015.

By 2015, China will also stop the production and use of POPs in pesticides.

The plan will be submitted to the State Council for approval in July, he said.

Under the Stockholm Convention, China will have to submit its national implementation plan to the convention's secretariat by November 11.

China signed the Stockholm Convention in May 2001 and it came into effect in China in November 2004.

Funding to control POPs will come from the central government, local governments and domestic companies as well as international organizations and foreign governments.

The Italian government has pledged to provide 7 million U.S. dollars in aid, the biggest sum pledged by a foreign government so far.

The fifth meeting to discuss China's implementation of the Stockholm Convention was held on Wednesday, with the attendance of more than 100 government officials and representatives from China, European countries, UN organizations and Italia, Germany, Norway, Japan and Finland.

"The Stockholm Convention can be successful only if it succeeds in China as the country is very influential in combating POPs," said Zoltan Csizer, a senior adviser of the UN Industrial Development Organization, at the meeting.

Of all the pollutants released into the environment every year by human activity, POPs are among the most dangerous. They are linked with cancer, allergies and hypersensitivity, and damage the central and peripheral nervous systems, which also cause reproductive disorders and disruption of the immune system.

According to the United Nations Environment Program, every person in the world carries traces of POPs in his or her body. POPs are highly stable compounds that can last for years or decades before breaking down.