You order pizza on Friday night. The box is empty and it’s made of cardboard, so it’s recyclable, right? Think again. The leftover grease and cheese actually rule it out from being a decomposable material. Even though you mean well, sometimes the most obvious things are not actually recyclable. We’ll walk you through the most common contaminants found at recycling facilities, so you can learn how to recycle properly.

What is Wish-Cycling?

According to Recycle Across America, wish-cycling is the tendency we have to determine the recyclability of an item solely based on our hope that this item will be recycled. It is a common mistake made everywhere and is, of course, carried out with the best of intentions.

Recycling contamination is any material or garbage that ends up in the recycling system, but cannot be recycled. Putting non-recyclable materials into your recycling bin ironically leads to less materials being recycled and adds to environmental costs. The average recycling contamination rate is 25%, which is 1 in 4 items. One single piece of paper can end up contaminating an entire stream of recycled materials, making them all end up at the landfill.

Top 9 Recycling Contaminants:

1. Plastic Bags

Plastic bags are a top offender on the what not to recycle list. These can range anywhere from a plastic grocery bag to Ziploc bags, newspaper bags and more. Instead of just throwing them away, here are a few plastic bag DIY projects to try at home.

“Loose bags act as ‘tanglers’ and wrap around sorting equipment at facilities. This causes facilities to shut down, sometimes multiple times a day, for workers to climb into machinery and remove all the bags. Other tanglers that most curbside programs do not accept include: holiday lights, ribbons, garden hoses, and other flimsy forms of plastic, like dry cleaner and bread bags. Many grocery stores serve as drop off sites for plastic film items.”
Beth Porter | Green America

2. Scrap Metal

Scrap metal, including brass, steel, iron and copper, can cause serious damage to recycling equipment. In addition, you can recycle scrap metal for cash payments at a local scrap yard in certain cases, which helps keep this useful material out of the landfill.

Green and Brown Colored Paper Shaped Into Trees

3. Shredded or Colored Paper

Shredded paper is a recycling no-no because it’s often too small to sort and either gets stuck on the belts of sorting machines or ends up on the floor. A great way to reuse your shredded paper is to start a compost bin.

Colored paper is on the what not to recycle list because in most cases, the paper will release its color. A good way to think of it is by comparing recycling to separating your colors and whites while doing laundry. You don’t want the colors to bleed all over your white clothes in the washer, and you don’t want colored paper to bleed over other recyclables.

4. Certain Plastics

While some plastics are fine to recycle, there are a few types that are not. All plastic containers are labeled with a resin identification code (RIC) that tells you which kind of plastic it is. You can find the RIC or number near the chasing arrow recycling symbol.

Plastics assigned number 1 and 2 (milk and juice jugs, water bottles and cleaning products) are almost always accepted in curbside recycling, but numbers 3, 6 and 7 are usually designated for the trash. Recycling programs vary from city to city, so make sure to follow the proper procedures for your area.

In most cities, for curbside recycling, you can play it safe by including clean plastic bottles (numbers 1 and 2), cans, paper and cardboard.

“Learn more about waste programs in your community. We’re often given the impression that recycling bins are magic that can eliminate bad impacts of anything we toss into them, and this isn’t the case.”
Beth Porter | Green America

5. Frozen Food and Takeout Boxes

Boxes that were designed for freezer foods like chicken nuggets or dinner entrées are coated in a plastic polymer spray that prevents freezer burn. This coating prevents the box from breaking down properly and cannot be recycled.

Cardboard takeout containers and pizza delivery boxes cannot be recycled either if they are contaminated with leftover food or grease. You can prevent recycling contamination by tearing off the soiled pieces and recycling parts of the container or box that are clean. Wax-coated takeout boxes cannot be recycled at all. Do a scratch test to see if wax comes off, and if it does, the box belongs in the garbage.

6. Specific Types of Glass or Ceramics

Glass from windows, mirrors or light bulbs are not recyclable materials. Porcelain, Pyrex, and old or broken dishes and drinking glasses are also not decomposable. Because of their chemical compositions, they have a different melting points than other types and will ruin the glass that is able to be recycled.

Sorting Machine at Recycling Facility

7. Lids or Caps on Glass Bottles

While some glass bottles are able to be recycled, their caps may not be. A metal lid from a jar can be rinsed and tossed into the recycling bin loosely, while plastic caps and lids from bottles should be throw into the garbage.

8. Flattened Containers

When your recyclable materials get to the facility to be sorted, the equipment separates the “flats” from “rounds,” so if you flatten your boxes or containers, the machine will mistake them for paper, which will contaminate all of the actual paper that they’re mixed with.

While it’s tempting to break down boxes in order to save space, make sure to leave your recyclable boxes in their normal state instead.

9. Hazardous and Bio-Hazardous Waste

This includes hazardous waste such as pesticides or automotive fluid and bio-hazard waste such as syringes, used diapers and other sanitary products. Find out how to safely dispose of these items in our hazardous waste guide.

“Recycling facilities have reported finding hypodermic needles, diapers, paint, car fluids, or other sanitary products in recycling streams. These are not recyclable, and “wish-cycling” these items not only contaminates recycling, but it poses health risks to workers.”
Beth Porter | Green America

How You Can Avoid Wish-Cycling

Now that you know what not to recycle, it’s important to know your city’s specific rules on recycling. Create a list of what your town accepts, and post it on your fridge or near the trash so you have a visual reminder.

“When it comes to recycling at home, it is best to stick with the basics, and contrary to what seems natural, when in doubt, throw it out. We are doing more harm than good by wish-cycling.”
Alexa Green | Recycle Across America

Most places no longer accept recycling in trash or plastic bags, so make sure all your items are loose in your bin. Single stream recycling is now the norm, so sorting different materials is unnecessary and will be done for you at the facility. Rinse, clean and dry any items that you can, and if they remain contaminated, throw them away so your whole collection of recycled materials doesn’t get wasted.

Focusing on eliminating wish-cycling and contaminated recycling has never been more important. The trash and waste we dispose of every day has a huge impact on our environment, and properly recycling the correct materials can help preserve our natural resources for future generations.

“Reduce the amount of waste you generate in the first place by minimizing your purchases of unnecessary single-use disposables, reusing what you have, and donating or up-cycling anything you don’t want.”
Sara Goddard | Green That Life

More Ways to Be Green

Looking to learn additional habits so you can live more sustainably? These posts will help you out: