A study from the Hong Kong plastics industry says that, contrary to expectations, the city's bag tax has increased the amount of plastic used in bags by more than 25 percent, prompting industry officials to question the 2-year-old law's environmental benefits.
The study found that use of the plastic bags targeted by the law — the T-shirt and die-cut bags commonly used at supermarkets and retailers — did drop substantially, as the law envisioned.
But it said the skyrocketing use of heavier garbage bags and reusable non-woven plastic bags as alternatives more than made up for that decrease, pushing overall use of plastic in bags of all kinds up 27 percent since the levy started in July 2009.
“We are concerned that the levy does not do any good for the environment,” said Rickly Wai Ki Wong, the executive vice president of the Hong Kong Plastic Bag Manufacturers Association, and an executive at Universal Plastic & Metal Manufacturing Ltd. in Hong Kong.
One of the main reasons, he said, is that residents have switched from reusing plastic shopping bags for trash to buying a lot more garbage bags.
Based on a survey of its 100 member companies that manufacture plastic bags, Hong Kong's 7 million residents used 78-80 tons of plastic per day in all types of bags before the levy started, but use about 100 tons a day now, Wong said.
The amount of plastic used for garbage bags went up 63 percent, and for non-woven bags went up 96 percent, while for the traditional T-shirt and die-cut bags, the plastic used measured by weight dropped 68 percent and 20 percent, respectively, the PBMA said.
Wong said the association believes the other main reason for the increase was the use of non-woven polypropylene bags, which while they are reusable and are increasingly popular, contain 30 to 50 times as much plastic as the traditional shopping bag.
Those bags need to be reused at least 30 times to equal the traditional shopping bag, Wong said.
Hong Kong's government is debating expanding the bag levy, including covering more retailers such as clothing stores or booksellers, and letting retailers keep the money collected for selling bags, rather than turning it over to the government.
The law started with its first phase in 2009, with about 3,000 of the largest retail stores, supermarkets, convenience stores and personal-health and cosmetics stores having to charge 50 Hong Kong cents (US6.4 cents) per bag.
Hong Kong environmental groups said the law has worked and should be expanded to the other 60,000 retailers in the city.
Government statistics show plastic shopping bag use has dropped by 77 percent at the stores covered, said Michelle Au, a spokeswoman for Friends of the Earth Hong Kong.
Local newspapers in Hong Kong reported that the amount of plastic bags disposed of in city landfills last year fell only 5.7 percent, however, because many stores are exempted from the tax.
Responding to the PBMA study, Au said that while the total use of bags has increased, she questioned whether that was because of the levy, and said it could be the result of more tourism or general economic development.
She also said that while the use of non-woven bags has increased, the 17 million non-woven bags used are only a small fraction of the 4.3 billion plastic bags used in the city in 2010.
Friends of the Earth argues that Hong Kong needs stronger action on waste reduction, as the volume of waste in the city has gone up 7.3 percent from 2005-09, in contrast with a government pledge at the time to cut it by 1 percent a year.
Friends of the Earth said broad policies like waste fees and producer responsibility laws are needed to address the “affluent lifestyles and consumption behavior” fueling Hong Kong's growing waste.
The group has singled out the bag levy in public comments as an “ideal strategy to address the root cause of a waste problem: the excessive use of plastic bags.”
A spokesman for Hong Kong's Environmental Protection Department said officials there consider the levy a success because it has changed consumer behavior by convincing people to bring their own bags to the supermarket.
EPD said disposal statistics are more-relevant measures of the effectiveness of the law than manufacturing figures, and said that “the reduction in the disposal of plastic shopping bags from the regulated sector [supermarkets, convenience stores, personal-health and cosmetics stores] outnumbers the increased disposal of garbage bags.”
Also, the agency said it has “stepped up publicity and public education so as to discourage excessive distribution” of non-woven bags, and said they are subject to the levy.
For the industry's part, Wong said he expects the government to expand the levy, but said the PBMA believes there should be an exemption from the fee for bags that are either biodegradable or have a high percentage of recycled content.
Wong said the association is still debating internally what specific standards to support in each of those areas.
When Hong Kong first began to debate a bag tax in 2006, the industry had concerns that its sales would drop, but Wong said the reverse has happened.
While the industry has not suffered in strictly business terms, the constant negative government and media attention has damaged its public standing, Wong said.