Paper bags use 4 times more water and energy, and creates 5 times more solid waste but it doesn’t leave something in the Earth that has seeped into everything we’ve known. Paper bags are biodegradable, plastic bags are a huge contributor to microplastics. There are no perfect solutions in life. Paper bags contribute to climate change less than plastic bags and don’t contribute to microplastics. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/291023/scho0711buan-e-e.pdf is a study that shows paper bags become “environmentally friendly” in 3 usages and plastic bags in 4. But the issue is that a lot of paper bags don’t make it to 3 uses and break before. So, if you know you are going to use the bag exactly once and then toss it. The best bet for climate change and microplastics is paper bags.

Paper bags also potentially contribute more to acid rain due to the chemicals they use to treat paper and fertilize the trees. But acid rain isn’t a big issue currently. We did well to prevent that. So it’s a balance of evils. It’s like a bunch of world disaster sliders that when you move one, others adjust. A little more acid rain, a little less climate change, and microplastics.

There is no perfect solution here. Cotton reusable bags have to be used 131 times to be environmentally friendly and frankly. I’ve not found what other environmental effects cotton manufacturing has on the planet but I bet you it’s more than just energy and climate change related.

So overall this isn’t a complete picture, no one has that. I use paper bags because it seems like the best solution currently. Recycling paper is relatively easy and something that some people do in high school or middle school. Besides recycling them they are also biodegradable, they completely break down and don’t harm the environment. You can’t recycle plastic bags due to the type of plastic it is so they are directly a waste product that’s non-biodegradable and photodegrade over 1,000 years.