Wanted: the next step to cut reliance on plastic

What's next after the plastic bag levy? It might be biodegradable plastic bags. Or eco-friendly packaging. That is, if the system lets it happen.

Professor Carlos Lo Wing-hung, who specialises in environmental governance at Polytechnic University, said the levy system was not conducive to innovative and creative solutions to the overuse of plastic bags.

'The levy system only suppresses consumer demand for [plastic bags], and it does not provide any incentive for the producers to come up with innovative ways to address the problem,' he said.

'This is not a sustainable approach as there is always a limit you can reach in cutting bag abuse, but beyond that limit, you might have to think out of the box.

'Producers are in a much better position, financially and technologically, to create these solutions than consumers. But under a levy system that allows retailers to keep the levy proceed is an extra blow to this innovation potential.'

Lo said the quality rather than the quantity of the plastic bags should be the future focus, after a full-scale levy scheme applying to all retailers was put into effect.

Bags could be made more environmentally-friendly, such as being biodegradable in a short period, while product packaging could be redesigned to avoid the consumption of more plastic bags, he said.

Dr Chung Shan-shan, a solid-waste management specialist from Baptist University, disagreed. She said a biodegradable bag was no solution to Hong Kong's mounting waste problem, no matter how short a life it had after being dumped in the landfills.

'The biodegradable bags will not help Hong Kong's urgent waste problem,' she said. 'While food wastes are all degradable in the landfill, we still want to control their disposal because we are simply producing too much waste now, and we have nowhere to dump them.'

Last year, Hong Kong dumped more than 4.4 billion plastic shopping bags in landfills. That is about 26,400 tonnes if each bag weighs about six grams. In all, the city dumped about 6 million tonnes of solid waste in the landfills in 2010, most of it kitchen waste.

Chung said most biodegradable bags could not be mixed with conventional plastic bags in recycling because the former were made of different materials. A massive application of biodegradable bags converted from agricultural crops might push up food prices, just as biofuels do.

Chung said the best step after the levy was to move ahead on regulations to control excessive packaging.

'It is time to deal with packaging abuses, and change the perception that consumer is king and that grand packaging is a guarantee of good sales,' she said.

Chung said a packaging regulation could target the layers of packaging as well as the weight. 'This is going to be another controversial regulation,' she said.