How to Dispose of Lye Properly

Lye is dangerous to human health so you must dispose of it safely and correctly.

According to the Canadian Office of Health and Safety, you should get rid of leftover dye from hair dye within 90 days of the it. There are many ways this can happen, such as when it becomes mixed with other chemicals.

So, how do you dispose of lye properly? Lye is highly corrosive and very dangerous.

That’s why it’s illegal to buy or store it in the home. It’s also illegal to dispose of lye down the drain or sewer.

What Is Lye?

Any metal’s hydroxide will dissolve in water to create a strong base solution like sodium hydroxide or potassium hydroxide.

Sodium hydroxide or potassium hydroxide will decompose when heated, releasing heat and water vapour in the process to form sodium carbonate, carbon dioxide and water vapours.

Lye is often found in households as a drain cleaner. Sometimes, lye is sold as drain cleaner and other entities as lye soap.

It is also used in cleaning ovens and cleaning glassware in commercial establishments, such as restaurants, hotels and motels.

Why Is It Important To Dispose Of Lye Correctly?

Lye, commonly known as caustic soda, is highly corrosive and can cause burns to the skin if exposed to it directly.

It is very acidic when it reacts with water so it’s harmful to human tissues if it comes in contact with eyes, skin and other body parts.

If the surface in question is your skin, it can also cause severe damage by dissolving the proteins found in your skin.

Lye is also extremely reactive, and when it comes in contact with metals, it can burn them.

This is why lye must be carefully disposed of after use. If you are not aware of the correct way to dispose of lye, you should hire a professional that knows how to get rid of lye.

How to Dispose Of Lye?

Wet Air Oxidation Solution

The Wet Air Oxidation Method is a somewhat more technologically-advanced way of getting rid of lye. What is required are three waterway filters, four caustic soda containers, a mixing tank, a generator and a holding tank.

The lye chemical is mixed with the tank water using an external mixer, and this mixture is then pumped into a holding tank.

Next, the caustic soda solution is then pumped into the generator where air is blown into it to produce oxygen bubbles.

Finally, the mixture of caustic soda solution and oxygen bubbles is then pushed into the first waterway filter.

At this point, the oxygen bubbles have turned the caustic soda solution into carbon oxide and carbon dioxide.

It then flows through the second waterway filter to return to its original state as caustic soda solution.

The lye solution then flows into the third waterway filter where it’s pushed through to the fourth container where it is collected and stored for later disposal.

Neutralize It

If done properly, this is an effective way of getting rid of your unused or unwanted lye.

Once you are aware of the different methods of disposing of lye, you can implement them in the best way possible.

Contact Your Local Hazardous Materials Drop-off Location

If you believe that disposing of lye will be a problem for you, you can contact your local hazardous materials drop-off location. They will be able to arrange shipment of your lye to their local landfill for proper disposal.

A water filtration system is awesome, but should you buy bottled water?

Bottled water has a number of impacts on the environment.

While assume that everyone is aware of the negative impacts bottled water has on the environment, some seem to forget all of the downsides when faced with a case of “free” water.

You may choose the closest site to buy bottled water from, but keep in mind that you are contributing to more pollution in the transportation process of the bottles.

Giving It Away

If you have too much lye, it may also be worthwhile to contact local hobbyists or artists to see if they can use it for their craft projects.

Giving it to someone else for free can also be a great way to reduce your environmental impact while getting rid of unwanted chemicals in your home.

Adding Water to Lye

Lye is a chemical that reacts violently with water, so you should never add water to a chemical that contains this ingredient.

When combined with the right quantity of an acid, however, it can be an effective solution for cleaning stains out of clothes.

Because vinegar or acetic acid is a dilute acid, you should always mix it with baking soda before adding it to the wash cycle to help neutralize any leftover acid before adding it to your clothes.

What to Do When Coping with Lye

Understand Emergency Procedures

When working with lye, be very cautious and treat it as though it’s highly corrosive and dangerous if ingested or inhaled.

Accidents are named that for a reason, so it is important to know what to do if the worst happens.

Proper Storage

When not in use, lye should be carefully stored in a well-sealed container so that air doesn’t come into contact with it.

The container should be somewhere it can get enough light and air without causing any damage to it.

This can be quite a challenge depending on your local regulations when it comes to storing chemicals in the home.

So, it is a good idea to store it in a safe place rather than leaving it lying around the house where it may get damaged.

Never use lye for cleaning surfaces you value when it reacts with the fumes; for example, you should never use it in the bathroom or around food.

Avoid Contact With Other Substances

Lye is a highly reactive material that easily reacts with other chemicals, so it is essential that it is stored properly to avoid an accident.

When storing it, make sure that you store it along with other chemicals that react in a similar way, such as bleach and ammonia tablets.

Lye is also very toxic to metal, so you should never store it with any type of metal canisters or containers.

When combined with water, it produces a tremendous amount of heat that can cause the container to burst if enough heat generates.

On the other hand, metals that are non-reactive to lye should be stored next to it safely.

Chemical Storage

When storing any chemicals in the home, it is essential that you inform all occupants of the home of the potential hazards involved and instructions on how to dispose of any chemicals safely.

A chemical storage facility is a great investment in order that you avoid the dangers of mixing different chemicals and using too much at once.


Lye is a chemical that easily reacts with materials used in the manufacture of other chemicals, so you should wear gloves and a mask when handling it at all times.

It is strongly advised that you do not wear any clothing that contains nylon or polyester, as these fabrics may react badly with the fumes.

Rather wear natural fibers like cotton or wool, as these materials are less likely to cause skin irritation.

Take all of the precautions necessary when working with dangerous substances such as wearing protective goggles and gloves.

Wear gloves, a mask, safety goggles, and any other protective clothing that is appropriate to your environment when working with this substance.


Dispose of lye in a well-ventilated place away from any sources of ignition or other flammable materials.

Work in a well-ventilated place and avoid breathing or ingesting the fumes.

Use ventilation fans to remove fumes from the air and change your clothes as soon as possible to ensure that you don’t get any residue on you.

When working with lye, you must always wear protective clothing such as gloves and goggles to avoid getting the chemical on your skin and causing irritation.

You may also use PVC or plastic aprons to protect yourself from the liquid.

Also Read: How to Dispose of Old Pillows


Lye is a caustic substance that should not be used without proper knowledge and preparation as it can cause serious harm if not handled correctly.

Its disposal needs extra consideration since lye is highly corrosive and can react with metals and other organic matter to produce hydrogen gas which can cause an explosion if released into the environment.