It is 2022 and single-use plastics are no longer in vogue. With major grocery chains moving away from doling out single-use plastic bags like Oprah, most of us have now become accustomed to bringing along our own reusable bags to the grocery store. But are these reusable bags doing as much good to the environment as we think they are?
The answer is: it’s complicated.
As consumers have become more aware of making ‘greener’ choices, many of us have taken to choosing more ‘natural’ products that are available on the market. However, natural does not always equate to better. Would it surprise you to hear that a single-use plastic bag might be less harmful to our environment? At this point you might be asking how that is even possible - single-use plastics are clearly bad, that’s why we’re eliminating them!
To better understand why a single-use plastic bag might not be the worst option, we first have to understand how to measure the environmental impact of products in general. Using the Life Cycle Impact Assessment (LCIA), the overall environmental impact of any given product can be quantified. This is done by assessing how a product is produced, how it is used, and finally how it will be disposed of.
Using this exact approach, a 2018 paper published by the Danish Environmental Protection Agency conducted LCIA’s for common grocery carrier bags available at Danish supermarkets. These carrier bags included various types of single-use plastic bags, bioplastic bags (often also marketed as compostable plastics), cotton tote bags, and paper bags. The study found that where reuse was not at all a consideration, LDPE (#4) plastic bags had the lowest environmental impact with reusing at least 1 time to offset climate impact before using it as a waste bin bag. On the other hand, paper bags were recommended to be reused at least 43 times to offset climate impacts before using it as a waste bin bag.
I cannot imagine extending the life cycle of a basic paper bag for that many uses.
And if that doesn’t surprise you, an organic cotton tote needs to be reused up to 20,000 times to fully offset its climate impact, whereas tote bags made with conventionally grown cotton requires up to 7000 reuses.
All this is not to say plastic bags are good and organic cotton totes are bad, rather, try to reuse what you have as much as humanly possible! In a society that pushes us to consume as much as possible, try to make do with what you already have. You don’t need a cute cotton tote bag to do groceries in, a plastic bag from the last time you did groceries can do the job just as well!