Plastic bag ban benefits ‘over-estimated’
COLES and Woolworths say the bag ban diverted about 4.7 billion single-use plastic bags from landfill in 12 months, but a research study says the policy may be doing more harm than good.
University of Sydney economist Rebecca Taylor studied a similar policy in California to analyse the behaviour of consumers when it comes to bags and recycling.
She said the stores gave out less bags, but the shopper still needed something to put rubbish in at home or pick up dog poo with.
"What I found was that sales of garbage bags actually skyrocketed after plastic grocery bags were banned," Dr Taylor told the NPR podcast Planet Money.
According to her study, the purchase of small plastic bags jumped by 120 per cent.
Dr Taylor said consumers typically used the reusable bags for rubbish, which was problematic because they're thicker than the single-use bags and take longer to break down in landfill.
"So about 30 per cent of the plastic that was eliminated by the ban comes back in the form of thicker garbage bags," she told the podcast.
Speaking on Channel 7's Sunrise, the economist cast doubt on the success of the environmental policy.
"If we don't consider the thickness and the types of bags people substitute to, we could be substantially over-estimating the benefits of the policy," Dr Taylor said.
Hazardous materials management expert Dr Trevor Thornton echoed the economist's concerns.
"Garbags are only used once," he told Sunrise. "They generally have more plastic, they're heavier, they're often coloured so there's chemicals and are often perfumed so there's chemicals in them.
"Sometimes the cotton bags or the reusable bags are the ones that are causing more environmental concerns than the plastic ones.
"We don't get that sort of data from the supermarkets or the retailers to say what is actually happening."
Aldi says its policy of never offering single-use bags has kept 40,000 tonnes of plastic from entering the environment, while nearly 5000 tonnes of plastic have been kept out of circulation from Woolworths alone since the supermarket plastic bag ban was introduced 12 months ago - equal to more than 780 African elephants.
Despite some controversial backflips and modifications to the environmental policy along the way, both major supermarkets have revealed its massive impact.
Woolworths has issued about three billion fewer plastic bags from its stores over the last year.
It says shoppers have embraced the new habit, with one in six transactions now including the purchase of a plastic bag, and that number is decreasing month-on-month.
Coles says the sustainable strategy has diverted 1.7 billion single-use bags from landfill, with data claiming seven in 10 of its consumers now remember to bring a reusable bag when they shop and a further two in 10 bringing them on more occasions than not.
Single-use plastic bags have been banned in South Australia, Queensland, the ACT and Western Australia, while Victoria is expected to follow in November.
Woolworths chief executive Brad Banducci said consumers were quick to embrace the change despite vocal criticism from portions of the country.
"We recognise change is never easy, particularly when it comes to something as habitual as grocery shopping," he said.
"Yet one year after we phased out single-use plastic bags, it's clear Australians have formed new habits and embraced a vastly more sustainable way of shopping with reusable bags."