Is paint hazardous waste?

The short legal answer

Under federal law, a waste is hazardous if it is on one of EPA’s lists or if it has one of four traits: it catches fire easily, eats through things, reacts violently, or leaks toxic chemicals.

Most leftover paint isn’t on EPA’s lists. So the question is whether it has one of those traits. For oil-based paint, the usual answer is yes, because it burns. For modern latex paint, the usual answer is no.

But there’s a big catch for homes. Federal rules exempt household waste from hazardous waste law, even after it’s collected and hauled away. That is why EPA calls it household hazardous waste: it can be dangerous, but it’s not regulated the same way as factory waste.

Is latex paint hazardous waste?

In most states, no. Latex paint is water-based and doesn’t burn easily. That is why many counties let you dry it out and put it in the trash. King County, WA, and Hennepin County, MN, both allow fully dried latex paint in the garbage with the lid off.

California is the exception. CalRecycle says latex paint waste is presumed hazardous in California. All paint there must be recycled or taken to a proper site, and you should not dry paint out to throw it away.

Even where latex isn’t hazardous, liquid paint still doesn’t belong in the trash. It can spill and make a mess when trash is collected. Onondaga County, NY, warns that liquid paint in the trash can lead to state fines.

Is oil-based paint hazardous waste?

Usually, yes. Oil-based paints and stains are made with solvents that burn. Federal rules call a liquid ignitable if its flash point is below 140 °F, and many oil-based products fall under that line.

From a home, it’s still exempt from federal hazardous waste rules. But almost every local program treats it as household hazardous waste. Never put it in the trash or down a drain. Take it to a paint drop-off or a hazardous waste site.

Paint thinner, mineral spirits and spray paint are in the same group. Thinner and spray paint aren’t taken at PaintCare sites, so they go to hazardous waste.

What about old paint?

Old paint can be more hazardous than new paint. EPA says the federal government banned lead-based paint for homes in 1978. Paint from before then may contain lead. Latex paint made before about 1991 may contain mercury, which some makers used as a preservative. Since August 1990, paint with mercury had to be labeled for outdoor use only, and since August 1991 EPA has banned mercury in all newly made paint.

Don’t sand, scrape or burn old paint or dried chips from old cans. Take old cans to a household hazardous waste site.

Paint from a business is different

The household exemption covers waste from homes, not businesses. A painting contractor, landlord or shop that throws out oil-based paint has to follow hazardous waste rules for businesses.

Very small businesses have the simplest rules. PaintCare uses the federal limit: no more than about 25 gallons (100 kilograms) of hazardous waste a month, and no more than about 250 gallons stored at once. Businesses under those limits can drop off oil-based paint at PaintCare sites. In Illinois, PaintCare takes oil-based paint from any business. Latex paint from any business is accepted everywhere PaintCare runs.

Never mix paint from a home with paint from a business. Keep them apart so it’s clear which rules apply to each.

What this means for you

• Latex paint: recycle it, or dry it out for the trash where your area allows it. Never dry it for the trash in California.
• Oil-based paint, stain and varnish: take it to a PaintCare drop-off or household hazardous waste. Never the trash.
• Spray paint and thinner: household hazardous waste.
• Paint from before 1978 or with no label: household hazardous waste.
• Business paint: check PaintCare’s business rules and your state’s rules before you drop it off.