How Do I Dispose of Mineral Spirits?

Mineral spirits is commonly used to thin oil-based paint and clean paintbrushes, but this type of solvent can also be used for other home-cleaning projects, like removing dried grout from tile or stripping away all the gunk that's gumming up your garden tools. Mineral spirits is a handy tool to have at your disposal ... until it's time for disposal. Leftover or unused mineral spirits poses some safety risks, so it must be handled with more care than your other household waste.

Some people might think of the term "mineral spirits" as just another name for paint thinner, but this isn't exactly accurate. Mineral spirits is a specific kind of solvent that is derived from petroleum and can be used to thin oil paint.

Paint thinner is a broader term used to describe any solvent that can be used to thin paint. Often, products labeled "paint thinner" are composed primarily of mineral spirits plus acetone and other ingredients but not always. For example, lacquer thinner is a kind of paint thinner that's designed for use with lacquer paints. It may be made from denatured alcohol instead of mineral spirits. Paint thinner formulas vary from product to product. There are even eco-friendly paint thinners now, which are derived from natural ingredients, like citrus peel.

These distinctions matter when you're choosing the right product for a job but not as much when you're disposing of them. Mineral spirits, traditional paint thinners, and other harsh solvents all generally need to be handled in the same way.

Because it's derived from petroleum and is flammable, never dispose of mineral spirits by putting it in your household trash or curbside recycling bin. Don't pour it down a drain or on the ground either. Mineral spirits is considered hazardous waste. Any unused mineral spirits must be properly handled and destroyed by trained professionals so it doesn't explode or leach harmful substances into soil or groundwater.

Town and city governments generally operate programs to collect household hazardous waste, like mineral spirits, oil-based paint, turpentine, antifreeze, and other toxic substances. Unless you live in or near a major city, there may be just one such hazardous waste collection site in your area. You'll have to drop off your own hazardous waste and may need to make an appointment in advance. Search online for your city name and "household hazardous waste" or visit your town or city's website for specific information, including guidelines for how to pack your toxic materials.

Do you use mineral spirits primarily to clean paintbrushes? If so, you can delay your trip to the hazardous waste collection site by reusing the same solvent over and over. Clean brushes in a wide-mouthed container with a lid, like a plastic Mason jar or empty glass jar. Afterward, cover the jar and let it sit for a few days until the paint solids settle to the bottom of the jar. When this happens, carefully pour clear mineral spirits back into the original container.

Let the paint jar sit with the cover off to let any remaining mineral spirits evaporate. (Set it far out of the reach of kids and pets.) When you're finished with the jar of dried paint sludge, screw on the top and dispose of it in your trash can.