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Greasy Pizza Boxes

Although pizza boxes are made from corrugated cardboard, which is recyclable, grease-soaked boxes with leftover food debris are not, as the paper fibers can't be separated from the food's oils during the pulping process.

17 Things You Thought Were Recyclable That Actually Aren't

While it's great to recycle as much as possible, you may be surprised to find out that some of the items you've been throwing in your recycling bin don't actually belong there. While many people recycle items to try and cut back on waste or even make money, putting nonrecyclable items with recyclable items contaminates the process. And a lot of items that are widely presumed to be recyclable actually aren't (pizza boxes, we're looking at you), so it can get confusing at times. If you want to recycle more efficiently and easily, keep reading for 17 things you may have been recycling for years that you actually shouldn't be (and spread the word).

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