Bagmania: Why Reusable Bags Aren't Always Eco-Friendly

Does the single-use bag tax work?

Single-use plastic bags are a huge burden on the environment. After just a few hours of use they can take hundreds of years to decompose, polluting soil and water with microplastics. To curb this problem the European Union introduced the so-called plastic directive, and in Poland a recycling fee was added in 2018. Because of it we pay 20 groszy for each plastic bag.

Have Poles reduced their use of single-use bags?

According to the Ministry of Climate, the average Pole used about 300 single-use bags in 2018. Eurostat data from 2021 show a drop to 23 per resident. Analysis of recycling fee revenues indicates we still use around 120 bags per person each year, as some retail chains bypass the system, inflating the statistics.

Swapping the plague for cholera?

In some places bans cover not only thin produce bags but also paper bags. An example is the state of New Jersey, where after the ban a surge in sales of thick reusable bags was observed — bags that are often used only once.

A Greenpeace report shows that in 2018 British supermarkets sold 57 “bags for life” per resident, and a year later that number grew by 4.5%. In Poland, 17 thick plastic bags per person were sold in 2022; although there are no data on cotton bags, the trend may be similar.

When is a reusable bag eco-friendly?

The ecological value of a reusable bag depends on how many times it is used. Producing a thicker bag requires more resources than making a thin plastic one. A 2020 UN report indicates that a polypropylene (PP) bag must be used 10–20 times and a polyethylene (PE) bag 5–10 times to reduce the carbon footprint compared to a single-use bag.

The most environmentally taxing bag is the cotton one — it needs 50 to 150 uses to match the plastic bag. Producing one kilogram of cotton consumes up to 20,000 liters of water, and the crops are often associated with heavy pesticide use and ethical issues during harvesting.

If we reuse a plastic bag as a trash liner that later goes to an incinerator, the Danish Environmental Protection Agency says a cotton bag would need to be used more than 7,000 times to be more eco-friendly.

Which bag is truly eco-friendly?

The most eco-friendly bag is the one you already own. It's worth keeping one in the car and one in your purse or backpack to avoid buying new bags on impulse. It takes an average of 66 days to build the habit of taking a bag with you, so don't get discouraged by small slip-ups.

If you forget your reusable bag, it's better to buy a single-use one and reuse it, for example as a trash bag or for packing vegetables. You can also take part in local bag-exchange initiatives such as Boomerang Bags, which allow bags to circulate repeatedly.