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Can You Burn Pressure Treated Wood in a Fire Pit?

Can You Burn Pressure Treated Wood in a Fire Pit?

It’s winter, and you have a huge pile of pressure-treated wood that remained after putting up your fence or assembling your deck. You are now wondering if you can burn the wood in your fire pit because the wood can absorb preservatives having undergone treatment. But before we dive in, here’s a brief definition of pressure-treated wood.

What is Pressure Treated Wood?

Just like the name suggests, pressure-treated wood is wood that has been treated using pressure. The wood is placed inside a pressure chamber filled with liquid preservative chemicals. If you are unsure whether your wood is pressure treated, look for half-inch long splits on the wood’s surface. These splits are the injection spots for the pressurized chemicals.

Additionally, pressure-treated wood has a dark brown or greenish color. The most common chemical used in the treatment is ACQ or alkaline copper quat. Copper is used because it is poisonous to fungi and insects and inhibits rotting. Once the wood is treated, it is less susceptible to damage from fire, water, corrosion, UV rays, fungi, and insects but not to moisture.

Can You Burn Pressure Treated Wood?

No. You should never burn pressure-treated wood. Burning poses great health dangers to living organisms because of the chemical preservative used in the treatment. When you burn this wood, the chemical preservatives are not destroyed. Instead, they are released into the atmosphere with the smoke.

Its ash and dust contain lethal chemicals because burning the wood releases the preservative. Therefore, burning pressure-treated wood is not a convenient disposal method for the wood.

Health effects of burning pressure-treated wood

The symptoms of burning pressure-treated wood are severe, recurring nosebleeds, crippling headaches, fatigue, seizures, and long disorientation periods. These negative effects are caused by inhaling arsenic poisoning from burning treated wood.

Environmental effects of burning pressure-treated wood

In addition to lacing the air with harmful chemicals, burning pressure-treated wood has other effects on the environment. Chemicals absorbed into the ground after burning this wood contaminate the soil and groundwater.

Additionally, the preservatives may leech into the surface of the wood. Therefore, you should seal the treated wood to extend its durability and adherence to the chemical preservatives to prevent them from leaching the wood’s surface. Generally, burning pressure-treated wood results in air, soil, and water pollution.

What happens if you burn pressure-treated wood?

Whether you burn it accidentally or intentionally, the harmful chemical preservatives will be released into the air, posing risks to human health and the environment. Inhaling burning pressure-treated wood smoke causes the following effects:

  • Upper respiratory tract infections
  • Respiratory inflammation
  • Lung cancer
  • Throat and lungs damage
  • Permanent irritation in bronchial tubes

If you accidentally ingest dust from pressure-treated wood, be on the lookout for damage to:

  • Your stomach
  • The kidneys
  • Intestines
  • The digestive tract

If your skin comes into contact with the treated wood, you will experience skin irritations from alkaline and copper and some allergic reactions to boric acid.

Can you burn pressure-treated wood outside?

No. The same harmful chemicals in the treated wood will be released into the air whether you burn the wood inside or outside. Burning exposes people to arsenic poisoning. Regardless of the purpose or location for burning, you will still expose yourself to toxic chemicals.

Burning treated wood can cause asthma-like symptoms, skin irritation, damage to the intestines and stomach, and breathing difficulties. Furthermore, the ash from treated wood is toxic and may be blown into the air and carried to the neighboring homes.

What to do if your neighbor is burning pressure-treated wood

It is important to bring up a conversation with them on the effects of burning treated wood. Inform them on the potential health risks they are exposing themselves and the neighborhood to and have them go for tests for contaminants in their body.

You can also send a complaint to the local authorities and let them handle the issue.

How to dispose of pressure-treated wood

With burning removed from the list of treated wood disposal methods, here are other options to use.

Store the wood in specialized bins, especially if you cannot dispose of it immediately. A specialized bin allows you to easily identify treated wood from other wood so that you do not recycle or burn it. Ensure to cut the wood before storing it in specialized bins.

Seek help from your local landfill. Since treated wood is harmful to the environment, you should ask for help from your local authorities to dispose of it. Reach out to confirm if the local landfill accepts treated wood and, if so, take your wood to them.

What chemicals are in pressure treated wood?

Wood was commonly treated using Chromated Copper Arsenate (CCA), but manufacturers decided to find more environmentally friendly and safer chemicals due to its hazardous effects on the environment and human health.

ACQ or Alkaline copper quat

This chemical contains a quaternary ammonium compound and copper and protects the wood against insects and decay-causing fungi. When near an ignition source or fire, ACQ may explode. Compared to Chromated Copper Arsenate (CCA), commonly used for treating wood, ACQ is relatively non-toxic upon exposure to skin or mouth. However, copper leaches out when you cut the wood.

Copper azole (CA)

This chemical makes the wood resistant to termites, fungi, and decay. However, CA leaches into the adjacent soil when used in the garden. But unless the copper residue is ingested, there isn’t a direct effect. However, exposure for children below eight years has acute toxicity on the skin.

Copper naphthenate

It has low toxicity to the skin, mouth, and nose. Inhalation, however, causes nasal membrane blockages and difficulty in breathing. When constantly exposed to the chemical, you are prone to weakened membranes and anemia, making you vulnerable to other toxins. The chemical also has carcinogenic compounds like benzene.

Polymeric betaine

This chemical can be used for outdoor furniture because of its low toxicity levels compared to CCA. However, burning this wood is still dangerous because it releases harmful elements into the air. Ensure to use safety goggles, a dust mask, and gloves when handling treated wood to protect yourself from harmful exposure.


They are poisonous to wood-boring insects and fungi but have low toxicity to humans.


You should not burn freshly treated or over 20 years old, pressure-treated wood. The chemicals used will be released into the air and hazardous upon inhalation regardless of the wood’s age. Therefore, it is important to keep your family and environment as safe as possible from the danger posed by burning treated wood.