How to Recycle & Dispose of Paint Thinner

Learn how to recycle or dispose of old paint thinner sustainably.

By Maryruth Belsey-Priebe

Fact checked by Sander Tamm

Recycling & Disposing of Paint Thinner
Recycling & Disposing of Paint Thinner / Sander Tamm / Ecolife

They solve your toughest paint removal problems. Whether you’re cleaning a used paint brush or washing out a rag you used while painting, paint thinners such as acetone, mineral spirits, and turpentine work well for removing oil-based paints. But these paint-removers come with environmental hazards you may not be aware of:

  • Acetone: Used in consumer products like nail polish remover and auto lacquer, acetone is a colorless, clear liquid that is somewhat toxic (should never be ingested or inhaled).
  • Mineral spirits: A petroleum distillate, mineral spirits are often used as a substitute for turpentine. They are less flammable and toxic than turpentine, but are still volatile and are acutely and chronically toxic due to high percentage of aromatics.
  • Toluene: Made from tolu tree byproducts as well as crude oil, this chemical is also used in nail polishes and adhesives and can cause dizziness and confusion. Toluene is very toxic in higher concentrations.
  • Turpentine: Though often derived from pine trees, turpentine can also be made from crude oil. It is highly flammable and should be handled with care.

How to recycle or dispose of paint thinner

So, what’s the safe way to recycle or dispose of paint thinners? Follow these steps for eco-friendly ways to handle your paint thinners to protect the environment and your health:

  • Don’t pour down the drain: Turpentine, paint thinners, mineral spirits, and other solvents should never be poured down the drain, into the septic tank, or into a storm drain as they are toxic to the environment and will contaminate groundwater.
  • Choose natural paint thinners: Instead of hazardous conventional paint thinners, look for natural paint thinners made from less toxic ingredients, like The Real Milk Paint Co’s Citrus Natural Solvent or Powdered Milk Paint RemoverBioShield Citrus Thinner.
  • Reduce consumption: If possible, try to purchase and use less of these toxic products. Either borrow from a family member, friend, or neighbor, or look for less toxic substitutes. And when buying new, be sure to purchase only as much as you need.
  • Give it away: Could your neighbor or friend use some paint thinner? If you’re moving or just cleaning house and want to get rid of unused paint thinners, find someone willing to take it off of your hands.
  • Add to solvent paint: If you’ve got leftover paint that’s oil-based, you may be able to add your paint thinner to it to thin it out and as a way of disposing of the hazardous waste.
  • Recycle through municipal paint collection: Paint thinners are considered household hazardous waste and therefore should be handled as such. Send your used product to a municipal hazardous collection site (call your local solid waste department for locations and events). 
  • Reuse, and reuse again: Paint thinners, mineral spirits, and turpentine can all be reused over and over again. As such, all you need to do is put the used product into a sealed container and leave in a safe place out of reach of children and pets. After some time, particulate matter (paint) will sink to the bottom. Then just drain off the clear liquid and put into a well-labeled clean container to be stored until you need it again. Pour the “soiled” residue into some kitty litter or shredded newspaper, let dry, and throw out with regular trash.
  • Paint thinner containers: When you’ve used up an entire can or container of paint thinner or other solvent, leave the lid off to let the container dry, then recycle with the regular plastics or metals. Paint residue, unless it’s more than an inch, will not hinder the recycling process.