The report, which ranks companies on their policies regarding chemicals and waste, gave the Beijing-based company top marks for its handling of discarded electronic products, known as "e-waste".

It praised Lenovo for offering recycling and other waste disposal avenues in all the countries where its products are sold and for reporting the amount of e-waste it recycles as a percentage of its sales.

"Given the growing mountains of e-waste in China - both imported and domestically generated - it is heartening to see a Chinese company taking the lead, and assuming responsibility at least for its own branded waste," international toxics campaigner Iza Kruszewska said.

But Greenpeace noted that Lenovo, which bought IBM's consumer electronics division in 2005, has yet to put on the market products that are free of the worst chemicals.

The other companies in the top five are Sony Ericsson, Dell and Samsung.

Sony and LG Electronics were criticized for opposing producer responsibility laws in the United States.

AGENCE FRANCE-PRESSE