Pressure-treated lumber is wood that has been put through a process where preservatives have been pressured into the wood. When wood is left untreated it is more likely to rot and see wood-boring insects. Pressure-treated wood is typically used for decks and fences, but it can be used in many other projects where longevity is of importance.
To pressure-treat wood, chemicals are basically infused into the wood making it resistant and longer-lasting. However, one thing that many people don’t know is that the chemicals used can be very toxic to us humans.
Today we have pressure-treated wood that is much safer for us then what was used in the past. In the past, we used CCA lumber, but it was known to be carcinogenic. Today we use a pressure-treated lumber called Alkaline Copper Quaternary (ACQ) or Copper Azole (CA-B), which is known to have fewer health risks.
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What is ACQ treated wood?
ACQ stands for Alkaline Copper Quaternary, it is a water-based wood preservative. It is also known as the new pressure-treated lumbar choice since CCA was banned. The reason for this new wood option is because of its low risk based on its elements of copper oxide and quaternary ammonium compounds.
ACQ acts as a fungicide and insecticide for the wood, which prevents it from rotting or decaying, resulting in a longer-lasting wood.
ACQ Lumber Safety
ACQ treated wood had been tested before to see if it was toxic to humans, however, after the test, the results informed us that ACQ wood is not toxic to touch and not toxic when orally exposed. The chemical components in the ACQ used for wood should not cause human harm and should not be a major concern when exposed.
The best place to find more information about the ACQ Human Risk Evaluation is through the PDF link I found on Walter Reeves gardening website and on the Q &A about Safety of ACQ. Click on Human Health Risk Evaluation of ACQ-Treated Wood link.
What is CCA treated wood?
CCA stands for chromated copper arsenate, which is a wood preservative that contains a variety of chemicals. CCA treated wood was the most common type of treated wood, but in 2003 they stopped treating residential lumber with it because of its health impacts.
CCA wood contains arsenic, and if breathed in or swallowed it can cause serious damages to your body. It can cause a sore throat quickly and irritation of the lungs, vomiting, and potentially death in certain circumstances. It is very toxic and if you suspect the wood to be CCA it might be better to redo the project rather than trying to save the wood.
CCA Lumber Safety
Do not burn CCA treated wood because of the possibility of breathing in smoke or ashes. Also, if cutting CCA wood wear eye protection and a respirator to prevent it from getting in your lungs. Furthermore, be careful because it can get on your skin and clothes, making it breathable after the job.
When CCA wood has aged you may not see a green tint, so it is very important to know what wood you are dealing with.
Sanding Pressure Treated Wood Dangers?
Sanding causes wood particles to become airborne where they can easily be inhaled. The dangers when sanding pressure-treated wood is the possibility of inhaling chemicals in the wood. Depending on the wood type, certain woods contain carcinogenic toxins that can cause serious health concerns.
As mentioned above, CCA would be a type of wood you need to be careful of. It contains arsenic which us cancerous and it could be inhaled when sanding. Inhaling high volumes of CCA wood at a time can cause irritation quickly, but more importantly, it can cause serious health issues such as asthma, upper respiratory infections, and since its carcinogenic, potentially cancer over a period of time.
I recommend completely avoiding sanding CCA treated wood because of its toxicity, but be aware if aged it may be difficult to tell.
Inhalation of ACQ pressure-treated wood dust is known to be much less toxic than CCA. However, I wouldn’t say inhaling it is ok. Still wear a dust mask and eye-protective gear, it is better safe than sorry.
Realistically, breathing in any type of wood dust could cause health issues in the future. Many studies on dust believe it is the cause for many health disorders down the road, such as bronchitis and other lung issues. if you can wear protective gear it wouldn’t hurt!
Can you sand pressure-treated wood?
Yes, you can sand pressure-treated wood but there are dangers you should be aware of. Always stay clear of CCA pressure-treated lumbar because of its carcinogenic characteristics. While ACQ is not known to be toxic to humans, try not to breathe it in.
Overall, sanding causes wood particles to become airborne and if not wearing proper gear it could easily be inhaled. Also, it could land in your eyes, on your skin, or on your clothes, which can be somewhat prevented. Take this into consideration when trying to stay clear of inhaling the wood particles.
Overall, sanding pressure-treated wood is possible with limited health concerns. However, this is only true with ACQ treated wood and not CCA, so know your wood and be safe.
Jamie is the founder of The Backyard Pros. When he was 15 years old he started working at a garden centre helping people buy plants, gardening products, and lawn care products. He has real estate experience and he is a home owner. Jamie loves backyard projects, refinishing furniture, and enjoys sharing his knowledge online.