Ten participants in a voluntary scheme to reduce plastic-bag use have handed out 80 million fewer of them since the pact's launch early this year, Secretary for the Environment, Transport & Works Dr Sarah Liao says. The three major supermarket chains have achieved 24-29% cuts, far above their 15% target.

In 2003, 372,000 tonnes of plastic bags were disposed of at landfills. This fell to 368,158 tonnes in 2004, and 362,080 tonnes in 2005. Based on the current average disposal cost of $125 a tonne for waste disposal at landfills, the costs of disposing of plastic-bag waste were $46.5 million in 2003, $46 million in 2004 and $45.2 million in 2005.

According to a survey conducted at landfills at the end of last year, the number of plastic shopping bags disposed of at landfills was estimated to be about 23 million a day, over 30% of which came from supermarkets, convenience stores, bakeries and the catering business.

Since early this year, the Environmental Protection Department has signed the voluntary pact with 10 major supermarket and retail-outlet chains. More details about the pact are available here.

To reduce the indiscriminate use of plastic shopping bags, Dr Liao said a study report on a plastic shopping bag levy - including its feasibility, options, level of charge and scope, the environmental benefits of various options and their impact on the trades - will be completed by the end of this year. The public and the trades will be extensively consulted on the proposal.