Bags require special sorting and processing machines ― and not every recycling plant has those. In most areas of the country, people should not mix plastic bags in with other recyclables. But people do, and on a massive scale, which causes severe technical problems at general recycling facilities.
Bags can “break the recycling equipment used to sort material by jamming up the gears of the conveyor belt,” said Mark Carpenter, assistant vice president of communications for the Institute of Scrap Recycling Industries, a nonprofit trade association that provides training and education on recycling.
Americans use 14 billion bags every year. Though it’s unclear how many are mixed in with curbside recycling, it’s not unusual for general recycling operations to shut down several times a day due to the catastrophe the bags cause, said John Hambrose, communications manager at Waste Management Inc., one of the largest sanitation companies in the U.S.
Recycling plant employees must remove tangled bags by hand and put them in a pile to be sent to a landfill.
What’s baffling is that plastic milk jugs and plastic bags are made out of the same material. “It seems stupid, but it’s literally an issue of machines not being suited to handle” plastic bags, said Margaret Sobkowicz-Kline, an assistant professor in the plastics engineering department at the University of Massachusetts Lowell.
Here’s how to properly recycle plastic bags
First, look up the rules for your area’s curbside collection, Carpenter said. If you live in one of the few places that accepts plastic bags with all other recyclables, you can disregard this article.
You can also bring your collection to large grocery retailers. Most will have a receptacle for disposing of used plastic bags. For this process to be most effective, it’s important your bags are dry and empty — so make sure you check for leftover paper receipts. From here, the bags are transported to dedicated bag-recycling facilities, Sobkowicz-Kline said. Here, the bags are melted down and turned into pellets that’ll be used to make something new.
However, the color of a bag can sometimes affect its recyclability. Colored bags mess with the automated sorting machines, Sobkowicz-Kline said. The colorants confuse the sensors and often must be hand-sorted out. The reject pile ends up in a landfill.
Some companies specialize in turning plastic bags into new products. Trex, for example, uses these items to make composite lumber for home decks. It accepts clean and dry grocery bags, bread bags, case overwrap (like the kind that covers a case of water bottles), dry cleaning bags, newspaper sleeves, ice bags and wood pellet bags. (Here’s a list of Trex drop-off locations around the country; most of them are grocery chains.) The company hosts an annual competition for schools, which compete to recycle the most plastic film.
If you’re not properly recycling plastic bags, it’s better to throw them away in the garbage rather than in the wrong recycling bin, Hambrose said. Even better, tie the bags in knots and put trash inside of them before you toss them: Hambrose said doing this will at least keep the bags from blowing away and ending up hanging from trees and fences.
When plastic bags escape collection networks, they can disrupt and block drainage systems, contributing to floods and adding toxins to water sources. They also pose a great risk to animals, especially those that mistake the bags for food. Nearly every seabird on the planet eats plastic, and the habit is believed to jeopardize the animals’ health, sometimes fatally, according to National Geographic.
Even if you’re a conscious consumer who grocery shops with a reusable tote bag, sometimes the use of a plastic bag can be unavoidable. What’s crucial is where these bags end up once you’re done with them.
This story is part of a series on plastic waste, funded by SC Johnson. All content is editorially independent, with no influence or input from the company.