Are Reusable Grocery Bags Any Better for the Planet Than Single-Use Ones?
Canadians use about 15 billion plastic grocery bags annually.
But since the federal government announced a ban on the sale of single-use plastics like cutlery, straws and checkout grocery bags, effective as of December this year, grocers have begun to replace their thin plastic bags with thicker, reusable ones. Sobeys Inc. (which owns and operates Sobeys, FreshCo and Foodland) reports that the company pre-emptively eliminated 800 million single-use plastic bags in 2019 by providing a reusable option at checkouts.
In a press release earlier this year, Loblaw (which includes Loblaws, Real Canadian Superstore and No Frills) claimed it has diverted 13 billion plastic grocery bags from landfills to date in its efforts to shift to reusable bags. Such bags cost the customer anywhere from $0.25 to $5.
The most common replacement for single-use grocery bags is the poly-woven variety, which feels like a cross between plastic and fabric. While it’s more durable than a traditional checkout bag, it’s still made from polypropylene or polyethylene, both of which are derived from fossil fuels.
“These are not renewable or sustainable sources, and they’re not compostable or biodegradable,” says Mohini Sain, director of the Centre for Biocomposites and Biomaterials Processing at the University of Toronto. It also requires additional manufacturing in order to make it shopping-ready.
Plastic fibres are woven into a cloth-like fabric and then treated with a plastic coating to protect the bag from soilage and moisture. “These processes are very energy-intensive,” says Sain. “The increase in the number of production processes means an increase in greenhouse gas emissions too.”
All in, the carbon footprint of a reusable grocery bag is equivalent to 109.2 kilometres of driving. Comparatively, the carbon footprint of a single-use plastic bag is equivalent to just eight kilometres of driving.
Of course, the more you reuse a bag, the more you decrease its environmental impact. For a durable polypropylene bag to have the same climate impact as one thin, single-use plastic bag, it needs to be used an estimated 10 to 20 times, according to a 2020 report from the United Nations Environment Programme. But this relies on a consumer behavioural shift that won’t happen overnight.
Sain says that getting shoppers to remember to bring their bags is difficult, especially given the relatively low price and plentiful availability of new bags at the checkout. But it’s not impossible.
“If customers are educated about the composition of these new reusable bags and the sizable impact their production has on the environment, it might help us take our culture back to a time before plastic bags were ubiquitous and make bringing your own bags the norm.”