The government faces the problem of how to dispose of at least five million televisions, four million fridges and six million washing machines annually from this year, State Environmental Protection Administration (SEPA) official Fan Yuansheng said.

At least five million computers and tens of millions of mobile telephones are already obsolete, Fan, who is vice-director of SEPA's pollution control division, told the official Xinhua news agency.

Chinese consumers own an estimated 370 million televisions, 150 million fridges, 190 million washing machines, 20 million computers and 200 million mobile phones, he said.

Some of the discarded "e-waste" is buried in landfill sites, and some is dismantled at small-scale recycling plants, Fan told the agency.

The recyclers try to recover metals like gold, silver, copper, tin and chromium, but large quantities of chemicals used in the recovery are often flushed into local rivers.

High-technology electronic gooods contain complex blends of metals, plastics and other materials, often including hazardous substances such as lead, cadmium and mercury.

"If they are not handled properly, these substances can pollute the soil, water sources and animal life, and pose a serious risk to human health," Fan said of the chemicals.

Efforts to control disposal of electronic waste are hampered by the lack of specialist regulations, said Mao Rubai, a pollution control official from the southeastern province of Fujian.

SEPA hopes to devise a system of fees and regulations giving responsibility for waste disposal to manufacturers of electronic goods, under the principle of "polluter pays", Mao told the agency.

The officials' remarks came as China released its annual report on the environment on Wednesday.

The report said the country had reduced the total volume of pollutants discharged, but that the overall situation was "still not optimistic".

It said seven major rivers remain heavily polluted and Chinese coastal waters were hit last year by 79 "red tides", which are mainly caused by agricultural-use nitrates and phosphates washed into the sea.

Officials from China, India, Malaysia, the Philippines, Singapore, Sri Lanka, Thailand and Vietnam pledged last November to combat the threat of "e-waste" imported, often illegally, from Western and other developed countries.

The United Nations Environment Programme said Asia faced a "growing deluge of electrical and electronic waste".