After the Masterpiece: Safe Paint Disposal

Hey Mr. Green,

I'm confused! There is a lot of contradictory advice on proper disposal of latex paint. What is the greenest method for dealing with latex paint on paint brushes once the job is done? Throw the brush away? Clean it with water in buckets and pour the residue on the ground? Wash brushes in sink and let the residue go down the drain? Other method? —Doug, in Newton, Kansas

What a useful query for all painting procrastinators. Next time the topic arises, we all can say, “But dear, we can’t just recklessly leap into a painting project without sufficient research into biohazards and disposal methods.”

For latex paint, the greenest method for cleaning brushes is simply to wash with soap and water and pour the liquid down the drain into the municipal sewer system. For septic systems, it’s better to wash and dispose of the residue in the regular garbage. Never just dump it on the ground or pour it into a storm drain, because it won’t get safely treated. One exception: In the unlikely event that paint is really old—made in 1990—or before, it should be handled like hazardous waste. (There may well be more danger in prepping a surface than in paint. For more about this, see the paragraph on safe prepping below.)

It’s all right to dispose of unused latex paint by allowing it to solidify and then putting it in the regular trash. You can hasten this process by mixing in some cat litter or similar absorbent. It’s best to use the lowest-VOC (volatile organic compound) brand, and for optimum safety make sure you have adequate ventilation. If a heating and air conditioning unit is in operation, block all vents in the room where you are working, except the cold air return if it’s the only one in the house. And, yes, follow the manufacturer’s instructions to the letter, even if the print is too damn small.

Oil-based paints (alkyds) are an entirely different matter. These paints and their cleanup solvents should never be poured down a drain or simply tossed in the garbage. The brushes should be cleaned with the solvent recommended by the manufacturer. The solvent can be kept in a jar and reused, because the residue will sink to the bottom. I hasten to add that it should be stored away from heat and light, and made inaccessible to curious youngsters who might want to test its flavor. If you must dispose of oil paint and solvents, contact your local household hazardous waste department. If you have trouble finding it, just go to earth911.com  and type in “household hazardous waste” and your Zip code. For more advice on painting in general, take a look at the EPA’s home remodeling advice. Your tax dollars at work, at least as long as the EPA is safe from the ravages of right-wingers and their political accomplices.

It’s important to add that lead or other heavy metals may be released when you prep a surface covered with old paint. Protecting kids from these metals is at least as important as preventing the little darlings from sipping paint thinner, because lead can impair a child’s mental development—and Lord knows there are already enough other toxic substances and ideas afloat to accomplish that damage. Therefore, be extremely cautious in scraping, sanding, and using paint removers. To find out more about precautions with surfaces that may contain lead, see the EPA’s advice on lead and its detailed advice for do-it-yourselfers  If you have other questions about it, you can even call the National Lead Information Center at (800) 424-LEAD.

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