How to dispose of acetone

Why acetone needs extra care

Acetone's flash point is about 0°F on Klean-Strip's safety data sheet. Its vapor can catch fire even in a cold garage. OSHA puts liquids like this in a higher-risk group than mineral spirits or turpentine. The sheet also warns that the vapor is heavier than air and can spread along floors to a pilot light or spark.

Acetone also mixes completely with water. That's why people think they can flush it. The Klean-Strip sheet says water mixed with more than 2.5 percent acetone still has a flash point. Above 8 percent in a closed container, a spark could set off a fire or explosion. Diluting it in a drain or sewer doesn't remove the danger.

Nail polish remover vs. a gallon of acetone

Most nail polish remover is mostly acetone. OPI's Original Polish Remover safety data sheet lists more than 70 percent acetone and a flash point of about 1°F. That sheet also says the product must not go out with household garbage or reach the sewer. California's list of wastes banned from the trash names fingernail polish remover by name. Hennepin County, Minn., lists it as household hazardous waste too.

What changes with the amount is how you handle it, not where it goes.

How to get rid of acetone, step by step

1. Use it up if you can. Klean-Strip says to use its acetone within one year of purchase, so don't buy a gallon if a quart will do.
2. Keep leftovers in the original container with the label on. Don't move acetone into a plastic drink bottle or food jar.
3. Close the cap tight. Acetone evaporates fast, and an open container fills the room with flammable vapor.
4. Find your household hazardous waste site or event. Search your county's website or ask your trash company.
5. Check limits and rules first. Many sites limit container size; Hennepin County's limit is 5 gallons per container.
6. Pack containers upright in a box, away from the passenger area, and drive straight there.

Can you let acetone evaporate?

For a damp cotton pad, effectively yes. For a cup or a can, no. The Klean-Strip safety data sheet warns against spreading acetone over a large surface because the fire and health risks "increase dramatically." A pan of acetone in a garage or yard is exactly that.

New York DEC lets residents mix less than one cup of leftover non-halogenated solvent with plain clay cat litter. You dry it outdoors and bag it for the trash. That is a New York rule for tiny amounts. California bans solvents from the trash entirely. Even where small amounts are allowed, a hazardous waste site is the safer choice for acetone.

What about the environment?

Acetone doesn't linger long in the air. The CDC's toxic substances agency says acetone occurs naturally in plants and some foods. It also says about half of the acetone in air breaks down within 22 days.

That doesn't make dumping it OK. The big risk with acetone is fire, plus vapors that irritate eyes, nose and throat. EPA also warns that hazardous products poured down drains can harm septic tanks and treatment plants.

Safety while you store it

• Store acetone in a cool, well-ventilated spot away from furnaces, water heaters, pilot lights and stoves, as the safety data sheet directs.
• Keep it out of reach of children. Breathing a lot of it can cause headaches and confusion, the CDC says.
• Never mix acetone with other chemicals to get rid of it. Hazardous waste staff need to know what's in each container.
• Wipe up small spills with sand, cat litter or other material that won't burn. Put it in a closed container and treat it as hazardous waste.
• An "empty" can still holds vapor and residue. The safety data sheet says not to reuse the container.

State rules at a glance