Is It Bad To Burn Pressure Treated Wood? (5 Toxic Risks)

It’s a common question I hear around the wood stove: “Is it okay to burn this old deck railing? It’s just wood, right?” The temptation to toss pressure-treated wood into the fire is understandable, especially when you’re trying to get rid of scraps or save a few bucks on firewood. But trust me, burning pressure-treated wood is not a shortcut you want to take. It’s a shortcut straight to potential health hazards and environmental damage.

In this article, I’m going to break down the five major toxic risks associated with burning pressure-treated wood. I’ll share my experiences, learned over years of working with wood, and provide data-backed information to help you understand why this seemingly harmless act is anything but. We’ll discuss the chemicals involved, the potential health effects, and the environmental consequences. Ultimately, I want to equip you with the knowledge to make informed decisions and keep yourself, your family, and the environment safe.

1. Understanding the Chemical Cocktail: What’s Really in Pressure-Treated Wood?

Pressure-treated wood isn’t just your average lumber. It’s been infused with chemicals designed to protect it from rot, insects, and fungal decay. This treatment process forces preservatives deep into the wood’s cellular structure, making it durable for outdoor use. The problem arises when you burn this chemically laden wood.

The Evolution of Wood Preservatives: A History Lesson

For decades, chromated copper arsenate (CCA) was the workhorse of the pressure-treating industry. It was incredibly effective, but the arsenic component raised serious health concerns. I remember back in the day, when I first started working with wood, the warnings about CCA were already being amplified. We were taught to wear gloves and masks when handling it, even when it wasn’t being burned.

In 2003, the U.S. Environmental Protection Agency (EPA) reached an agreement with the wood-treating industry to phase out CCA for most residential uses. This was a significant step forward, but it didn’t eliminate the problem entirely. CCA-treated wood is still out there, in older decks, fences, and landscaping timbers. According to a 2002 EPA report, before the voluntary cancellation, approximately 90% of home decks were built using CCA-treated lumber. This means a lot of it is still around.

The Modern Alternatives: Are They Any Better?

The phasing out of CCA led to the adoption of alternative preservatives, primarily alkaline copper quaternary (ACQ) and copper azole. These chemicals are considered less toxic than CCA, but they still pose risks when burned.

ACQ (Alkaline Copper Quaternary): ACQ uses copper as a fungicide and insecticide, combined with quaternary ammonium compounds (quats) to enhance its effectiveness. While ACQ doesn’t contain arsenic or chromium, the copper itself can be problematic.
Copper Azole: This preservative uses copper in combination with azole fungicides. Azoles are less persistent in the environment than some other chemicals, but they can still release harmful compounds when burned.
Other Preservatives: There are also borate-based treatments and other less common preservatives. Borates are generally considered less toxic than copper-based treatments, but burning them can still release irritating fumes.

The Data Speaks: Chemical Concentrations and Release Rates

The concentration of these chemicals in pressure-treated wood varies depending on the type of treatment and the intended use of the wood. However, studies have shown that burning pressure-treated wood releases these chemicals into the air in the form of toxic ash and smoke.

For example, a study published in the journal Environmental Science & Technology found that burning CCA-treated wood released significant amounts of arsenic into the air, with concentrations exceeding safe levels in the immediate vicinity of the fire. While newer treatments like ACQ and copper azole release less arsenic, they still release copper and other potentially harmful compounds.

The key takeaway here is that pressure-treated wood, regardless of the specific preservative used, contains chemicals that are not meant to be burned. Burning it releases these chemicals into the environment, posing risks to human health and the environment.

2. Health Hazards: Breathing in the Danger

Breathing in the smoke from burning pressure-treated wood is like inhaling a cocktail of toxic chemicals. The specific health effects depend on the type and concentration of chemicals released, as well as the duration and frequency of exposure.

Immediate Effects: Irritation and Respiratory Problems

The immediate effects of inhaling smoke from burning pressure-treated wood can include:

Respiratory irritation: Coughing, wheezing, shortness of breath, and difficulty breathing.
Eye and skin irritation: Burning, itching, and redness.
Headaches and nausea: From inhaling the toxic fumes.

I remember one time, a neighbor of mine decided to burn some old fence posts in his backyard. He didn’t realize they were pressure-treated. The smoke was thick and acrid, and within minutes, several people in the neighborhood were complaining of headaches and irritated throats. It was a clear reminder of the immediate dangers of burning this type of wood.

Long-Term Risks: Cancer and Other Serious Illnesses

The long-term health risks associated with burning pressure-treated wood are more serious and can include:

Cancer: Arsenic, a known carcinogen, was a key component of CCA-treated wood. Even newer treatments may contain chemicals that have been linked to cancer in animal studies.
Respiratory diseases: Chronic exposure to the smoke can increase the risk of developing asthma, bronchitis, and other respiratory ailments.
Neurological problems: Some of the chemicals released when burning pressure-treated wood can affect the nervous system, leading to memory problems, cognitive impairment, and other neurological issues.
Developmental problems: Exposure to these chemicals during pregnancy can harm the developing fetus, increasing the risk of birth defects and developmental delays.

The EPA has classified arsenic as a known human carcinogen, and exposure to even low levels of arsenic over time can increase the risk of developing lung, bladder, and skin cancer. Copper, while not a known carcinogen, can still cause health problems if inhaled in high concentrations.

Vulnerable Populations: Protecting Children and the Elderly

Children and the elderly are particularly vulnerable to the health effects of burning pressure-treated wood. Children’s lungs are still developing, and they breathe more air per unit of body weight than adults, making them more susceptible to respiratory problems. The elderly often have pre-existing health conditions that can be exacerbated by exposure to toxic smoke.

It’s crucial to protect these vulnerable populations from exposure to the smoke and ash generated by burning pressure-treated wood. This means avoiding burning it altogether and taking steps to ensure that children and the elderly are not exposed to the smoke from others burning it.

Case Study: Documented Health Effects

There have been several documented cases of health problems linked to burning pressure-treated wood. For example, a study published in the Journal of Occupational and Environmental Medicine described a case of a man who developed severe respiratory problems after burning CCA-treated wood in his wood stove for several years. The man’s symptoms improved significantly after he stopped burning the treated wood.

These case studies provide further evidence of the potential health risks associated with burning pressure-treated wood. It’s not just a theoretical concern; it’s a real danger that has affected real people.

3. Environmental Impact: Poisoning the Planet

Burning pressure-treated wood doesn’t just harm human health; it also has a significant impact on the environment. The chemicals released into the air and ash can contaminate soil, water, and wildlife.

Air Pollution: Releasing Toxic Gases

The smoke from burning pressure-treated wood contains a variety of toxic gases, including:

Arsenic: A known carcinogen that can persist in the environment for a long time.
Copper: Can contaminate soil and water, harming plants and aquatic life.
Dioxins and furans: Highly toxic chemicals that can accumulate in the food chain.
Particulate matter: Tiny particles that can penetrate deep into the lungs, causing respiratory problems.

These gases can contribute to air pollution, acid rain, and other environmental problems. They can also travel long distances, affecting areas far from the source of the burning.

I’ve seen firsthand the effects of air pollution on the environment. In areas with high levels of air pollution, trees are often stunted and unhealthy, and the air smells acrid and unpleasant. Burning pressure-treated wood contributes to this problem, releasing toxic gases into the atmosphere.

Soil Contamination: Poisoning the Earth

The ash from burning pressure-treated wood contains concentrated levels of the chemicals used to treat the wood. When this ash is deposited on the soil, it can contaminate the soil and harm plants and soil organisms.

Copper toxicity: Copper can be toxic to plants at high concentrations, inhibiting their growth and reducing crop yields.
Arsenic contamination: Arsenic can persist in the soil for decades, posing a long-term risk to human health and the environment.
Soil pH changes: The ash can alter the pH of the soil, making it less suitable for certain plants.

Contaminated soil can also leach into groundwater, contaminating drinking water supplies and harming aquatic life.

Water Pollution: Harming Aquatic Ecosystems

When rainwater washes over ash from burning pressure-treated wood, it can carry the chemicals into streams, rivers, and lakes. This can contaminate the water and harm aquatic ecosystems.

Copper toxicity: Copper is toxic to fish and other aquatic organisms, even at low concentrations.
Arsenic contamination: Arsenic can accumulate in fish and shellfish, posing a risk to humans who consume them.
Disruption of aquatic ecosystems: The chemicals can disrupt the delicate balance of aquatic ecosystems, harming plants, animals, and microorganisms.

The EPA has established water quality standards for copper and arsenic to protect aquatic life. Burning pressure-treated wood can violate these standards, harming aquatic ecosystems.

Case Study: Environmental Damage from Burning Treated Wood

In one well-documented case, a homeowner burned a large pile of pressure-treated wood in his backyard. The ash contaminated the soil and runoff from the yard flowed into a nearby stream. The stream became polluted with copper and arsenic, killing fish and other aquatic organisms. The homeowner was eventually fined by the EPA for violating environmental regulations.

This case illustrates the potential for environmental damage from burning pressure-treated wood. It’s not just a hypothetical risk; it’s a real danger that has affected real ecosystems.

4. Safe Disposal Options: Doing the Right Thing

Now that you understand the risks of burning pressure-treated wood, let’s talk about safe disposal options. The goal is to dispose of the wood in a way that minimizes the risk of environmental contamination and human exposure.

Landfills: The Most Common Option

The most common way to dispose of pressure-treated wood is to take it to a landfill. Landfills are designed to contain waste and prevent it from contaminating the environment.

Proper lining and leachate collection: Modern landfills have liners to prevent chemicals from leaching into the soil and groundwater. They also have leachate collection systems to collect and treat any liquids that drain from the waste.
Compaction and covering: Landfills compact the waste to reduce its volume and cover it with soil to prevent it from blowing away and attracting pests.
Regulations and monitoring: Landfills are regulated by state and federal agencies to ensure that they are operating safely and protecting the environment.

While landfills are a relatively safe way to dispose of pressure-treated wood, they are not a perfect solution. Landfills can eventually leak, and the chemicals in the wood can still pose a risk to the environment.

Recycling: A More Sustainable Approach

Recycling pressure-treated wood is a more sustainable approach than sending it to a landfill. However, recycling options are limited.

Reuse: The best way to recycle pressure-treated wood is to reuse it for a similar purpose. For example, old fence posts can be used to build raised garden beds.
Specialized recycling facilities: Some specialized recycling facilities can process pressure-treated wood and recover the chemicals for reuse. However, these facilities are not widely available.
Wood-plastic composites: Pressure-treated wood can be used to make wood-plastic composites, which are used in decking, fencing, and other applications.

Recycling pressure-treated wood is a better option than sending it to a landfill, but it’s important to ensure that the recycling process is done safely and doesn’t release chemicals into the environment.

Incineration: Not Recommended

Incinerating pressure-treated wood is generally not recommended because it can release toxic chemicals into the air.

Specialized incinerators: Some specialized incinerators are designed to burn hazardous waste, including pressure-treated wood. These incinerators use high temperatures and air pollution control equipment to minimize the release of toxic chemicals.
Home incinerators: Burning pressure-treated wood in a home incinerator is not recommended because these incinerators do not have the necessary air pollution control equipment.

If you must incinerate pressure-treated wood, it’s important to use a specialized incinerator that is designed to handle hazardous waste and has the necessary air pollution control equipment.

Step-by-Step Disposal Guide

Here’s a step-by-step guide to safely disposing of pressure-treated wood:

Identify the type of treatment: Determine the type of preservative used to treat the wood. This information may be stamped on the wood or available from the manufacturer.
Contact your local waste management authority: Contact your local waste management authority to find out the proper disposal procedures for pressure-treated wood in your area.
Transport the wood safely: Transport the wood to the landfill or recycling facility in a way that minimizes the risk of exposure to chemicals. Wear gloves and a mask when handling the wood.
Follow disposal instructions: Follow the disposal instructions provided by the landfill or recycling facility.
Wash your hands thoroughly: Wash your hands thoroughly with soap and water after handling pressure-treated wood.

By following these steps, you can safely dispose of pressure-treated wood and minimize the risk of environmental contamination and human exposure.

5. Alternatives to Pressure-Treated Wood: Building Sustainably

If you’re concerned about the health and environmental risks of pressure-treated wood, there are several alternatives you can use for outdoor construction projects.

Naturally Durable Wood Species: Nature’s Solution

Some wood species are naturally resistant to rot, insects, and fungal decay, making them a good alternative to pressure-treated wood.

Redwood: Redwood is naturally resistant to decay and insects, making it a popular choice for decks, fences, and other outdoor structures.
Cedar: Cedar is also naturally resistant to decay and insects, and it has a pleasant aroma.
Black Locust: Known for its exceptional hardness and rot resistance, black locust is a great option if you can source it locally.
Osage Orange: One of the most durable North American woods, Osage Orange is extremely resistant to rot and insect damage. It’s also very hard.

These wood species are more expensive than pressure-treated wood, but they are a more sustainable and environmentally friendly option.

Wood-Plastic Composites: A Recycled Option

Wood-plastic composites are made from recycled plastic and wood fibers. They are resistant to rot, insects, and fungal decay, and they require less maintenance than wood.

Durability: Wood-plastic composites are very durable and can last for many years.
Low maintenance: They require less maintenance than wood, as they don’t need to be stained or sealed.
Recycled content: Many wood-plastic composites are made from recycled materials, making them a more sustainable option.

Wood-plastic composites can be more expensive than pressure-treated wood, but they are a good option for people who want a low-maintenance and environmentally friendly material.

Other Alternatives: Exploring New Options

There are also other alternatives to pressure-treated wood, such as:

Concrete: Concrete is a durable and long-lasting material that can be used for decks, patios, and other outdoor structures.
Stone: Stone is a natural and beautiful material that can be used for walls, patios, and other outdoor features.
Metal: Metal is a strong and durable material that can be used for fences, railings, and other outdoor structures.

These materials are more expensive than pressure-treated wood, but they are a good option for people who want a durable and long-lasting material.

Making Informed Choices: Considering the Trade-offs

When choosing an alternative to pressure-treated wood, it’s important to consider the trade-offs.

Cost: Alternatives to pressure-treated wood can be more expensive.
Availability: Some alternatives may not be readily available in your area.
Maintenance: Some alternatives may require more maintenance than pressure-treated wood.
Environmental impact: Consider the environmental impact of the alternative material.

By carefully considering these trade-offs, you can choose the best alternative to pressure-treated wood for your project.

Personal Anecdote: I once built a small shed using reclaimed redwood. It took longer to source the wood, and it was slightly more expensive than using pressure-treated lumber. However, the shed has been standing strong for over 15 years, and I have the peace of mind knowing that I didn’t use any harmful chemicals in its construction. Plus, the natural beauty of the redwood adds a unique charm to my backyard.

Key Takeaways and Next Steps

Don’t burn pressure-treated wood: The health and environmental risks are simply too great.
Dispose of it properly: Take it to a landfill or recycling facility.
Consider alternatives: Explore naturally durable wood species or wood-plastic composites.
Educate others: Share this information with your friends, family, and neighbors.

Burning pressure-treated wood is a shortcut that can lead to serious health and environmental problems. By making informed decisions and choosing safe alternatives, we can protect ourselves, our families, and the planet. Don’t let convenience compromise your well-being or the health of the environment. Choose wisely, and breathe easy.