7 Things You're Probably Recycling Incorrectly

flat lay shot of plastic bag, reusable bags, reusable coffee cups, and plastic items

Treehugger / Kasia Surowiecka

Simple recycling mistakes of common items can contaminate a whole batch, sending it to landfill instead of a new life as something else.

Recycling is amazing. Recycling is ridiculous. It is amazing that we are grappling with such an astronomical amount of waste; it is ridiculous that we create this much waste in the first place. But maybe even more so than amazing and ridiculous: Recycling is complicated!

While some municipalities make curbside recycling fairly straightforward, others places require complex schematics, spreadsheets, and a PhD in material sciences to understand how to properly sort one’s household trash. It can defeat the best of us, but we forge on. Unfortunately, however, if we make a mistake we can mess up a whole batch of recycling, defeating our best intentions as the whole tainted shebang gets sent to landfill.

As The New York Times reports, this is even more likely now that China, one of the world’s biggest importers of recyclable waste, will begin rejecting shipments that are more than 0.5 percent impure.

The thing is, most of us want everything to be recyclable ... and so we err on the side of “put it in the bin.” The Times notes that waste managers often call this wishful or aspirational recycling. Yep, guilty as charged. The Times also offers some “key offenders” when it comes to recycling things that we shouldn’t be, which we've included here.

1. To-go coffee cups

woman in pink cardigan at picnic table reaches for reusable pink and teal coffee cup

Treehugger / Kasia Surowiecka

This is a somewhat regular TreeHugger topic of rant. A paper coffee cup should be recyclable, right? But no, and grrrr. Single-use coffee cups are lined with polyethylene, which is great for keeping the cup from becoming a mess of wet paper, but very difficult and expensive to recycle. Meaning that most places consider the cups as trash.

Since a consumer can’t tell if a cup is lined or not, it’s recommended not to add them to recycling unless you know that your municipality recycles them. The New York City Department of Sanitation, for example, does accept “paper cups with non-paper lining.”

Of course, you could just use a reusable to-go coffee cup, or be like an Italian and drink your coffee at the coffee shop.

2. Pizza boxes

opened oily pizza box on top of closed pizza box with chef branding

Treehugger / Kasia Surowiecka

Cheese is oily. There is cheese on pizza. Pizza comes in cardboard boxes that get saturated with pizza cheese oil ... since the oil can not be separated from the cardboard, the recycled material becomes much harder to sell.

Again, however, check with your area. Some places will accept dirty pizza boxes; and at the very least, you can tear out the greasy parts and recycle the rest (including the top of the box, which should be clean).

3. Dirty containers

kid's hands rinse out plastic cup in kitchen sink before recycling

Treehugger / Kasia Surowiecka

“Washing out food scraps from recyclables can be just as important as putting the right thing in the recycling bin,” Jackie Lang, a spokeswoman for Waste Management in Oregon, tells The Times. Even if the container is allowable in your area, a take-out food container or a milk carton with bits of food or liquid can render a whole batch contaminated. Rinse, repeat, and you should be good.

4. Yogurt cups (and their friends)

three glass jars of yogurt with three spoons on wooden table

Treehugger / Kasia Surowiecka

Another complication is that rules change. Plastics 3 to 7 (used for things like yogurt cups, spread tubs and vegetable oil bottles) were once allowed in most places in the U.S. But now that China has banned used plastics, many municipalities no longer accept them since there is no longer much of a market for them.

Check you local rules. As far as yogurt goes, a lot of brands are now available in glass jars; even better, make your own!

5. Bottle caps

hands twist off green bottle cap on plastic bottle on kitchen counter

Treehugger / Kasia Surowiecka

Do you recycle plastic bottles with their caps? Plastic and plastic, makes sense, right? But some places do not allow caps; and some places do as long as the cap is firmly screwed on to the bottle. Again, check with your local rules.

6. Shopping bags

reusable mesh shopping bag with oranges and bananas on kitchen counter

Treehugger / Kasia Surowiecka

Oh, the bane of shopping bags. While most people in most places know they can't toss shopping bags in bulk into the plastics bin, many people will use a shopping bag as a receptacle for bottles and toss the whole thing in the recycling. The Times writes:

While we might wish that plastic bags — notorious for dissolving into microplastics and killing wildlife — could be sent to processors with our other recycling, they shouldn’t be. They create a nightmare for waste managers by plugging up machinery. So remember to dump your recyclables out of the plastic bag when putting them in the recycling bin.

If you haven’t transitioned to reusable shopping bags, it is really easy once you get the hang of it. Totes are so much more comfortable and durable than the single-use ones, and you know, they don’t kill sea creatures.

7. Dirty diapers

reusable cloth diapers on baby blanket with cartoon bees

Treehugger / Kasia Surowiecka

For real? According to the nation’s waste managers, it’s true. Now that’s aspirational recycling. To be fair, it’s good that people are at least trying; and given the mostly plastic composition of disposable diapers one can see where they’re coming from. But A) they are made of a number of different materials and B) if a few drops of milk contaminate a batch, think of what a diaper full of baby waste would do.