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Can You Pour Rubbing Alcohol Down the Drain? Safe Disposal Tips

rubbing alcohol on table

Rubbing alcohol has many uses in our day-to-day life, from cleaning to disinfecting, and its results may seem like magic. However, it also comes with an expiration date and the time to dispose of it will eventually come. The simplest method is to pour it down the drain, which is safe in small quantities.

Rubbing alcohol is a combination of isopropyl and water. Small amounts of rubbing alcohol can be poured down the drain, but isopropyl must be diluted first. While it is generally safe, it does require some thought and precaution.

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What Is the Difference Between Isopropyl and Rubbing Alcohol?

Isopropyl is pure alcohol with no other added ingredients, while rubbing alcohol is a mixture of isopropyl and water and sometimes contains other ingredients. Some rubbing alcohols include essential oils that can help relieve specific ailments, such as aching muscles.

Isopropyl is usually used in industrial settings while rubbing alcohol is safe for home use. The majority of rubbing alcohol brands will contain 70% isopropyl alcohol.1 Both products may include risks with their use, but because isopropyl is more concentrated, it is considered more hazardous.

hands holding alcohol spray bottles
Image Credit: cottonbro, Pexels

Is Rubbing Alcohol Safe for Septic Tanks?

Rubbing alcohol is safe for septic tanks in small amounts because it is soluble. Disposing of rubbing alcohol down the drain in high quantities and doing it frequently is not recommended. That is because high quantities can cause a disruption in the balance of bacteria in your septic tank.

Will Rubbing Alcohol Damage the Plumbing?

A small amount of rubbing alcohol will not cause damage to your pipes because it can be diluted with water, but you need to take caution when doing so. If you pour bleach or other cleaning agents down your pipes, along with rubbing alcohol, they may combine and contaminate the air. Chloroform is created by mixing bleach and rubbing alcohol, which is highly toxic.2 It can become corrosive, cause irritation to the eyes, nose, and respiratory tract, and can cause damage to your lungs and liver.

While this is very unlikely, it is vital to understand the potential risks so you can make an informed decision.

Can You Pour Rubbing Alcohol Down the Drain?

You can pour rubbing alcohol down the drain if the concentration is less than 24%. It is best to pour it down the drain when it is diluted. 1 cup of rubbing alcohol should be diluted with 10–20 cups of water. You should also avoid disposing of large quantities of rubbing alcohol as it can eventually kill off the bacteria in your septic tank.

How to Dispose of Rubbing Alcohol

Disposing of rubbing alcohol doesn’t include an involved safety protocol, but it does require some forethought. Here is how you can safely dispose of rubbing alcohol.

As mentioned before, a small amount of rubbing alcohol can be poured down the sink, so if you have a bit left in your bottle, this is the best way to go about it.

  • Open your faucet and allow the water to run
  • Pour the remainder of your rubbing alcohol down the drain hole
  • Keep the water running and allow it to run for another 5 minutes so that the alcohol can dilute
Image Credit: kaboompics, Pixabay

If you have a full bottle of rubble alcohol that you need to dispose of, you can add it to the trash, but you should do so safely. Close the cap tightly and ensure the bottle is labeled clearly with care instructions.

Other Uses for Excess Rubbing Alcohol

Because rubbing alcohol is also flammable, you can use it to light fires instead of disposing of it. Use it only outdoors in fire pits, but be cautious when lighting it, and try to avoid inhaling the initial smoke.

Leftover rubbing alcohol can also be used to:

  • Clean windows and blinds
  • Dissolve windshield frost
  • Clean your screens
  • Remove ink stains
  • Erase permanent markers
  • Remove ticks from dogs
Cleaning window using sprayer_Vladimir Miloserdov_Shutterstock
Image Credit: Vladimir Miloserdov, Shutterstock

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While it is encouraged to use rubbing alcohol before it expires, it is okay to pour a little down the drain as long as it is flushed with water. The accumulation of rubbing alcohol in a septic tank can disrupt the balance of important bacteria, and if it mixes with bleach in your pipes, it can become highly toxic. Pouring rubbing alcohol down the drain is better left as a last resort as there are many uses for it, even after it has expired.

Featured Image Credit: Maridav, Shutterstock


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