Once the paint is on the walls, what should you do with the can?

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Every year in the United States, homeowners throw out 64 million gallons (242 million liters) of unused interior and exterior paint [source: United States Environmental Protection Agency]. That's enough paint to paint 3,878,788 miles (6,242,304 kilometers) of highway stripes. To put that into perspective, it's enough paint to paint 16 solid highway stripes from the Earth to the moon [source: DownEast.com, NASA]. It's also enough to fill 128 Olympic swimming pools [source: U.S. Department of the Interior]. Every year.

Does all of this waste pose a hazard to the environment? Is there a way to dispose of old paint that doesn't involve throwing it out? And if it can't be used, what are the safe, responsible ways to get rid of it? We'll answer these and other questions on the following pages.

Before you can decide how to dispose of old paint, you'll need to determine what kind of paint it is. There are basically two types of paint: oil-based and latex. They have different ingredients and must be handled differently while painting and when you're done. Head to the next page to see what to do with each.