By now, you've heard that plastic bags aren't great. But a new study has revealed that discarded plastic bags are doing a lot more than taking up space in landfills — they're destroying marine life in incredibly short periods of time.

 

A new study published in Environmental Science and Technology found that plastic litter, and plastic bags in particular, smothers marine life and kills a variety of organisms.

 

Researchers from Trinity College in Dublin and Plymouth University in England found that over the course of a nine-week period, plastic bags were able to smother coastal sediment, blocking light and oxygen flow for the micro-algae beneath the bags. And since those algae are the basis for larger marine food chains, their being smothered could affect worms, bivalves, and eventually fish, Phys.org explains.

 

If you think you're doing the environment a favor by using biodegradable plastic bags, that might not be true either: The researchers found that the marine effects were the same for biodegradable and regular plastic bags. Nine weeks was enough time for the ecosystems to be affected, but not enough time for the bags to break down.

 

Phys.org notes that plastic litter accounts for roughly 80 percent of all litter in marine systems. Reusable bags are the best solution, but if you end up with plastic ones, taking them to a bag return for recycling instead of throwing them away could still make a huge difference.