Allergic reaction to pressure treated wood has not entirely gone away despite the banning of use of toxic chemicals in treatment processes.
Manufacturers today treat wood with Quarternary Ammonium Compounds (ACQ) and Alkaline Copper (AC).
These chemicals are less toxic and do not leach into the soil like creosote and Chromated Copper Arsenate (CCA).
Today, one of the most common allergic reactions to pressure treated wood include: dermatitis, a skin condition that causes irritation, dryness, or blisters.
Other conditions include; dryness and sore throat, conjunctivitis etc.
The new chemicals in treated woods do not result in severe health hazards as before. But they still cause allergies.
The discussion below sheds more light to allergic reactions as a result of exposure to toxins from pressure treated wood. Please keep reading…
What Is Pressure Treated Wood?
Pressure treated wood has preservatives or fire-retardants to extend and preserve its life span. In addition, the treatment removes air from the lumber, replacing it with a chemical.
Pressure treatment protects the lumber from ‘wood-ingesting insects like termites and wood rot caused by fungal decay.
Even better, a fire-retardant treatment helps the wood to char quickly after flame exposure, reducing the flame and smoke during a fire.
Pressure treating lumber provides deep chemical penetration and retention. This way, you get uniform protection for wood products.
Also, the treatment formulation meets the appropriate building code requirements and wood standards.
It is also computer-controlled and efficient with today’s advanced formulations.
The industrial procedure is as follows.
- The treating plant orders the wood from various mills. Then, it checks the material for moisture content to confirm the levels are not too high for the preservative process.
- Forklifts position the lumber on a train and move it into a vacuum pressure vessel. Then, you close the doors and seal the cylinder.
- Use an industrial vacuum pump to force air from the vessel and the wood.
- Flood the areas with the preservative solution.
- Next, adjust the cycle times and pressure settings based on the needed retention levels and wood species under treatment.
- Remove the excess solution from the wood using the industrial vacuum pump. And run a final vacuum within the cylinder to extract excess chemicals.
- Open the door and remove the wood, placing it on a drip pad for about 24 to 48 hours.
- Finally, give every lumber piece an end tag to denote the plant name, location, abbreviation, application, preservative’s name and initials, chemical retention levels, and approved inspection agency’s trademark.
- The wood is ready for loading and shipping to distribution companies.
Some western wood species experience incisions because they are resistant to preservative penetration. Thus, the chemical penetrates along the grain.
These wood types undergo small incisions before the pressure-treating procedure.
And the practice is common for all sawed Douglas fir three inches or more.
Chromated copper arsenic (CCA) was the primary preservative for the longest time.
But the chemical’s toxic nature caught the Environmental Protection Agency’s attention. So, they began strict oversight of companies using CCA.
Also, in 2003, the wood industry responded to negative publicity by stopping the production of residential CCA.
While views differ over the danger of the preservative, most consider existing treated wood safe.
But homeowners must take precautions by applying a penetrating oil formula every few years.
In addition, older pressure treated wood needs periodic sealant application. The process locks in the dangerous arsenic chemicals, making the wood safe to use.
Similarly, treat newer pressure treated surfaces with a finish to protect the lumber from corrosion and weathering.
The best way to think about this exercise is that treating wood protects it from internal decay, whereas applying a sealant keeps it from external damage.
A topcoat also prevents the lumber from drying too fast, causing excessive warping.
We have three primary pressure treated wood types: Alkaline copper quaternary, borate, and non-combustible.
Alkaline Copper Quaternary
The manufacturer treats the wood with an environmentally friendly solution containing ammonium alkyl and copper.
It is safe and delivers a durable structure. But please avoid using it for areas experiencing food or animal feed contact.
These products contain water-based mineral salt solutions. The components also retain the lumber’s colors and protect it against insects, fungi, mold, and mildew.
However, constantly wet conditions can wash the treatments, posing an environmental hazard.
Borate is safe and does not alter the wood’s color. But it should not come in contact with kitchen utensils, food, or animal feed.
This pressure treated material is less applicable for household applications or residential projects.
Please note that pressure treatment does not prevent weathering and corrosion. Instead, it only avoids harmful rot and insects.
Therefore, applying a sealant on the surface is advisable for a longer-lasting project.
Lastly, pressure treated lumber is ideal for outdoor building work or applications needing fire-retardant-treated wood.
You can also use the material for framing, railing, decks, fencing, garden boxes, landscape walls, gazebos, sandboxes, arbors, swings, porches, and sheds.
What are Allergic Reactions
Allergic reactions are how your body responds to an allergen: A chain of events resulting in an allergic reaction.
People get an allergic reaction when their immune system overreacts to harmless substances.
Further, the body responds by producing allergic antibodies when you expose it to a specific allergen.
These antibodies find the allergens and attempt to remove them from your system. As a result, releases histamine, causing allergies symptoms.
The immune system protects the body from diseases, infections, and viruses.
Therefore, it does ‘whatever it takes to fight foreign substances introduced into the system.
Some people are allergic to other substances such as latex, pet dander, certain foods, mold, insect stings, and dust mites.
Thus, they will show allergy symptoms with constant exposure.
Please note that an allergic person may not react to an allergen the first time.
But it is prudent for them to avoid even minor exposures to avoid reactions.
You can have an allergic reaction after eating, inhaling, or touching an allergen. Besides, doctors can use allergens to diagnose allergies.
They can also inject them into your body as treatment.
Other treatments include decongestants, asthma medicines, antihistamines, nasal steroids, and immunotherapy.
Symptoms of allergic reactions vary from mild to severe.
You get mild symptoms with a first-time exposure. But they worsen when you inhale, touch, or eat the allergen.
Mild reactions include:
- scratchy throat
- Itchy red skin spots
- Sneezing and nasal congestion
- Watery/itchy eyes
- Allergic rhinitis.
Severe reactions are:
- Abdominal pain or cramping
- Chest pain and tightness
- Swallowing and breathing difficulties
- Anxiety or fear
- Heart palpitations
- Face flushing
- Vertigo or dizziness
- Face, eyes, or tongue swelling
Anaphylaxis is a sudden but severe allergic reaction that develops seconds after exposure to an allergen.
This reaction results in life-threatening symptoms such as:
- Airway swelling
- Breathing inability
- Sudden and severe blood pressure drop.
Always get immediate medical assistance if you experience anaphylaxis. It can result in death with delayed treatment.
What are the Allergic Reactions to Pressure Treated Wood?
Manufacturers use different chemicals for various wood products. Further, they treat wood to repel fungus, mold, insects, and moisture.
However, sensitivity to these preservatives causes allergic reactions.
Therefore, the user may experience skin rashes, redness, hives, blistered skin, and itching or burning sensations.
Various scenarios lead to the above reactions. They include:
Skin Exposure to Pressure Treated Wood Dust
Copper is a highly corrosive compound. Even worse, it causes severe skin irritation when combined with alkaline.
The irritation occurs from brief and prolonged contact with the wood dust.
The Boric Acid used during the wood treatment can penetrate the skin, leading to allergic reactions and severe sensitivities.
In addition, the skin may absorb monoethanolamine used in ACQ wood treatment and experience highly corrosive reactions.
Didecyldimethylammonum chloride is another chemical in Quaternary Ammonium Compounds. It has a caustic nature and permanently harms animals’ eyes and skin.
Ingestion of Pressure Treated Wood Dust
Although ingesting pressure treatment wood is rare, never eat, drink, smoke, or consume anything in the work area.
Wood dust ingestion causes permanent damage to the stomach, intestines, kidneys, liver, and digestive tract.
The average treated wood consumption causes extreme abdominal discomfort and mild intestinal problems.
Inhalation of Pressure Treated Wood Dust
Inhaling wood dust permeated with ACQ chemicals results in extreme inflammations.
Moreover, repeated exposure leads to permanent bronchial tube irritations.
Thus, the victim may suffer from asthma, prolonged colds, or upper respiratory tract infections.
Bronchitis may become chronic in some cases, even after minimizing the dust exposure.
Monoethanolamine in treated wood damages the lungs and nervous system, especially when inhaled in larger quantities.
Lastly, didecyldimethylammonum chloride scars the throat and lungs, causing ongoing respiratory issues.
Treated wood is dangerous because of the preservatives used during the treatment process.
Moreover, although these compounds give the wood longevity, they affect human and environmental health.
Therefore, adhere to necessary precautions when using the wood.
For instance, encourage children to wash their hands after handling wooden outdoor equipment.
In addition, please avoid serving food on treated playground equipment or wood tables. Health experts link bladder and liver cancer to treated lumber.
Is Pressure Treated Wood Safe for Picnic Tables?
Pressure treated wood is safe for outdoor furniture, including benches, picnic tables, and chairs. But consider using alkaline copper quaternary treated lumber for added safety.
Further, avoid using the wood in places experiencing direct food and water contact.
For example, kitchen countertops, cutting boards, or areas where pets and kids can chew and ingest the lumber.
Alternatively, you can use Cedar, Douglas fir, or Redwood. They are water-resistant and available in most lumber yards.
These wood types are also lightweight, making them suitable for picnic tables.
Can You Use Pressure Treated Wood for Vegetable Garden?
Although pressure treated wood is safe, it is not wise to use it where the preservatives may become a food component.
However, you can use an impervious liner between the wood and the soil when there are no alternatives.
Gardeners used treated wood in raised beds and as posts until December 31, 2003.
The Environmental Protection Agency (EPA) banned selling wood treated with Chromated Copper Arsenate (CCA) for home use.
Its concerns focused on leaching arsenic from the treated lumber into the soil, contaminating plants.
Different suppliers developed two compounds to replace CCA wood in the residential woodworking space.
But health experts still debate if the product is safe for vegetable gardens.
These chemicals are copper azole (CA-B) and alkaline copper quat (ACQ). They have copper and a fungicide but no arsenic.
The copper keeps insects away, and the fungicide prevents soil fungi from damaging the lumber.
On the other hand, the fungicide in ACQ is quat and is also used in swimming-pool products as a disinfectant.
Generally, pressure treated wood can be toxic or non-toxic. It all depends on the chemicals used in the treatment process.
For example, lumber treated with chromate copper arsenate can leach arsenic, a very toxic compound.
Thus, the CCA-treated wood should only be used for construction work.
Please also avoid lumber treated with black creosote. It is a smelly coal tar derivative unsafe for food products.
Conversely, copper is a less toxic preservative. Besides, it is safer than all other chemicals used for residential use.
Alternatively, consider using decay-resistant lumber if you do not feel safe using treated lumber for a vegetable garden.
You can also line the interior walls of a raised garden with heavy plastic sheeting. This way, you keep the chemicals from seeping into the soil.
Lastly, choose a different material to grow pure organic foods. Besides, using untreated wood is much easier to meet high standards and purity.
How to Dispose of Pressure Treated Wood
Salvage and reuse are the first priority in keeping pressure-treated lumber from the waste stream. Besides, the wood will not need disposal if you recycle it.
So, try to reuse treated wood whenever possible. In addition, it will still serve the purpose if it meets the design requirements.
Pressure-treated wood contains chemicals that protect it from moisture, rot, and insect damage.
These preservatives vary with lumber type and application. But they include pentachlorophenol, Chromated Copper Arsenate, creosote, and ammoniacal copper zink arsenate.
These compounds’ positive side is that they extend lumber’s useful life. Further, the wood lasts 20 to 30 times longer than standard wood.
Unfortunately, the chemicals are also highly toxic. Besides, wood with CCA falls under the hazardous waste category.
Thus, you must be careful during disposal lest the preservatives leach into the water table or soil.
Even worse, they cause environmental and health problems.
So, follow the recommendations below if you must dispose of treated lumber.
Sell Your Pressure Treated Wood
You can sell your treated wood depending on the lumber type. Getting cash for the product certainly beats throwing it away.
Dispose of Your Regular Trash
Your regular waste disposal company can haul away pressure treated wood. However, please adhere to their pick-up requirements for easier coordination.
Take to an Eco-Friendly Landfill
Opt for an environmentally-friendly landfill if possible. Fortunately, more and more landfills are popping up around the state. So, you have no excuse.
These landfills have large protective liners at the bottom to prevent the preservatives from migrating into the soil.
Thus, the surrounding remains uncontaminated.
Bring It to Hazardous Waste Recycling Facility
Most towns, municipalities, and cities have facilities providing safe recycling or hazardous products.
The entity charges a fee for pressure treated wood. But at least you know the wood is in safe hands.
Repurpose Your Treated Wood
You can repurpose pressure treated wood to serve new applications. Hence, it won’t get to the landfill or trash can.
However, please avoid using it indoors for obvious reasons. And get creative outdoor projects.
In addition, always wear a mask when cutting treated lumber. Otherwise, you’ll inhale the chemical-contaminated sawdust.
The wood can also come in handy for flower boxes. Only do not grow herbs or food intended for human consumption therein.
Landscaping is another use for pressure treated wood. Further, it works well for sidewalks, garden edging, and retaining walls.
You can turn your treated boards into robust sawhorses for other Do-It-Yourself applications.
Finally, pressure treated boards are suitable for repairing boat lifts and docks. They are water-resistant and will add longevity to your structures.
Use Safe Wood Alternatives
There are safer alternatives to pressure treated lumber. They include cedar, redwood, stone, metal, recycled plastic, salvaged wood treated with safe materials, and lumber treated with less toxic chemicals.
Unfortunately, we do not have abundant resources for adequately disposing of treated lumber. Therefore, the best solution is to avoid using treated wood.
Also, consider alternative materials when working on a shed or garden bed. This way, you are sure of optimal safety.
Safety Precautions When Handling Pressure Treated Wood
Please refrain from using any treated wood where the lumber comes into direct or indirect contact with drinking water.
Nonetheless, incidental contact with bridges and docks is acceptable under current federal guidelines.
Also, do not use the lumber with beehives or where it comes in contact with animal or human food.
Keep Penta-and Creasoted-treated lumber for structural uses in your home, decks, playground equipment, and areas where wood meets livestock drinking water.
Additional precautions include:
- Only use visibly clean, treated wood free from surface residue for decks, patios, and walkways.
- Wash exposed areas thoroughly after working with pressure treated lumber. Also, clean up well before eating, drinking, and using tobacco products.
- Launder clothes before reuse if sawdust and preservatives accumulate on clothes. In addition, wash these garments separately from other household clothing.
- Put on goggles to safeguard your eyes from flying particles when machining and power sawing treated lumber.
- Wear a must when cutting, drilling, or sanding the wood.
- Work in a well-ventilated area for enclosed locations.
- Take scrap wood to the dump.
- Please avoid burning treated lumber lest you vaporize the chemicals. And allow them to hitch microscopic rides on smoke particles into your eyes, nose, lungs, mouth, and nose.
Is Pressure Treated Wood Safe for Indoor Use?
Pressure treated wood is not safe for indoor wood. Besides, ACQ-treated lumber is a health hazard due to its toxicity.
The wood has chemicals designed to withstand water and elements. But they can significantly affect the user when ingested.
Similarly, tropical exposure also leads to mild or severe effects, depending on the exposure level.
Treated wood dust is easy to inhale and ingest. In addition, it facilitates long-term skin exposure, resulting in significant health effects.
How Do You Tell If Wood Is Chemically Treated?
Sometimes, you may wonder how to tell if the wood is chemically treated. Besides, it is easy to lose track of what’s what when working in the lumber business.
So, check out the tips below on identifying treated wood. Some strategies are a little more traditional, while others are pretty straightforward.
Check the End Tag or Stamp
Stamps are a sure way of identifying treated lumber in the industry. They are visible and easy to interpret.
You can find these stamps on cut dimensional lumber, crates, pallets, and other wood products.
Moreover, they are abbreviations like FDN, Bor, or ACQ. These initials show different chemical treatment forms.
On the other hand, wood tags are usually conspicuous if present. They include vital information, including the chemicals in the lumber, the company involved, and species.
The markings are easy to spot in normal circumstances and should be present on every product. This way, you will know whether you got the correct product.
So, look for a stamp informing you it is pressure treated lumber. Besides, it is easy to find an elaborate marking on the product.
Marks like ‘FDN’ refer to ‘Foundation and confirm the wood to be a safe product. Also, you can use it as a base for underneath home flooring.
Borate-treated wood is equally safe. It is suitable for indoor applications and features Bor, Tim Bor, and Hi Bor stamps.
In addition, the preservative protects the structure against rot and termites. But please use it carefully to avoid contaminating the soil.
Please refrain from using wood treated with Chromated Copper Arsenate (CCA). The chemical has arsenic, which is hazardous to human and animal health.
Keep away from lumber stamped L P22. The marking shows that the wood contains arsenic.
In addition, although it is less toxic than its counterpart, it is unsafe for home furniture and indoor applications.
A fact sheet will show you whether the wood is treated or not. Moreover, it has a list of preservatives used in lumber treatment.
For example, you’ll know the wood has undergone treatment if it has copper and tebuconazole.
The manufacturer produces the fact sheet and ensures that it accompanies the lumber.
You can even request one from the company if you don’t find it with the product.
Fact sheets give a description of what you ordered. They include your order details such as species and dimensions, order size, and the form of treatment.
Sometimes you do not find the tag/stamp or fact sheet but still have to tell whether the wood is pressure treated.
Here, we have a few tricks lumber professionals use to distinguish the wood.
For instance, lumber undergoes various chemical reactions during treatment. Hence, depending on the chemical, it turns into various blue or green shades.
You may have seen olive green or blue wood. Well, this is the result of pressure treatment.
Various chemicals result in different colors, as seen below.
Copper Azole (CA) – Brown
Wood with CA has little or no odor. Further, it can be Type A with boric acid, tebuconazole, and copper.
Conversely, the lumber can be Type B with more tebuconazole and copper but no boric acid.
CA gives wood structures superior protection against termites, mold, fungi, and other insects.
Chromated Copper Arsenate – Green
Wood with a greenish hue feature chromium, copper, and CCA or arsenic.
Previously, CCA was the most effective compound. It kills termites, fungi, and other pests. But it is poisonous to the soil and people.
Therefore, health agencies no longer recommend it.
ACQ – Tan or Olive
Alkaline Copper Quat (ACQ) has a copper and a quaternary ammonium compound. It protects the wood against decay fungi and insects.
In addition, you can use it for structural support like fence posts.
Over time, these wood colors may fade. But the chemical treatment evidence remains inside the lumber.
Consider cutting against the wood grain when checking older lumber for treatment. The process should reveal the flesh underneath.
Fortunately, the wood will still have slight color distortion. So, it won’t be hard to tell.
Also, the above is not a defect but a sign that your wood is pressure treated.
Smell the Wood
Chemicals used to treat wood are highly effective in preserving the material. However, they give off a strong and easy-to-detect scent.
Thus, consider your wood treated if it smells oily or like gasoline.
New pressure treated lumber has a chemical smell, whereas non-treated wood does not. So, check for natural odor during your assessment.
As a result, keep freshly treated lumber in a well-ventilated area. This way, you won’t inhale the toxic fumes for long.
Unfortunately, the chemical smell dissipates after a while. Hence, the above is not foolproof and only works on recently treated wood.
Also, the method may not work if you are working with older wood.
Use a Wood Testing Kit or Swipe Test Kit
Many commercial labs and pressure treated wood suppliers offer a test kit. It helps to identify treated lumber quickly.
Find the Retention Level
The retention level shows how many preservatives were left in the wood after pressure treatment.
This way, you can tell whether the wood has chemicals.
In addition, the higher the retention level, the more durable the lumber.
Generally, residential construction lumber measures eight ft. (244cm) to 16 ft. (488 cm). But you will also find some 2x4s and 2x6s sold as precut 92 ⅝ inch options.
Moreover, wood featuring chemicals is usually broader and thicker than regular wood.
It is essential to tell whether the wood is pressure treated so that you can take the necessary precautions.
For instance, certain preservatives have arsenic and are only suitable for specific applications. And they can damage your health with prolonged exposure.
Also, you do not want to use CCA-treated wood to build a deck.
Similarly, you need the correct pressure treated wood type for the project.
For example, the material must have a high enough retention rating whether in contact with the ground or in an area with high moisture levels.
Frequently Asked Questions
Some of these questions include:
What Chemicals Are in Pressure Treated Wood?
Manufacturers use a wide chemical range to treat wood. They include:
This preservative protects fence posts, piers, marine pilings, and railroad timbers from moisture exposure.
However, shipyard builders and railroad workers are at high risk. Excessive creosote exposure causes liver cancer.
In addition, handling creosote-treated wood causes hives and other allergic reactions for people sensitive to petroleum products.
- Oil-borne Chemicals
These chemicals are found in stadium bleachers, patios, utility poles, decks, and band stands to ward off wood borers, beetles, termites, and ants.
Manufacturers also add waterproof ingredients into the mixture to prevent mold, fungal growth, and decay.
- Waterborne Chemicals
The wood used in home and building construction has a wide array of waterborne preservatives.
They include Sodium Borates (SBX/DOT), ACQ-D Carbonate, Copper Azole (CBA-A & CA-B), Chromated Copper Arsenate (CCA-C), Alkaline Copper Quat (ACQ-C or ACQ-D), and Micronized Copper Quat (MCQ).
Which Wood Preservative Has the Lowest Toxicity?
Manufacturers use several chemicals to treat lumber. And the Environmental Protection Agency (EPA) is always conducting tests on treated wood.
This way, they can ensure that the material is safe for the environment and human use.
Also, EPA approves several preservatives based on their low toxicity levels.
These compounds include alkaline copper quaternary (ACQ), copper naphthenate, copper azole, borates, polymeric betaine, and copper-HDO (Ncyclohexyldiazeniumdioxy-copper).
Are There Safe Alternatives to Pressure Treated Wood For Outdoor Furniture?
We have safer options for outdoor furniture like redwood, white oak, cypress, and western cedar. In addition, they work pretty well and deliver long-lasting results.
These wood types are also appropriate for exterior applications as they resist decay, rotting, and pesky insects.
Further, the heartwood, the tree’s inner part, is more resistant to insects and rot than the sapwood, the outer part.
However, these lumber types are more pricey than other options and pressure treated wood. Therefore, you’ll need to pay more if safety is non-negotiable.
You can still use pressure treated wood for outdoor furniture. Only ensure that it is not toxic.
Also, consider using alkaline copper quaternary (ACQ) as it is less toxic than Chromated Copper Arsenic (CCA).
ACQ binds well to wood fibers and protects the structure from decay, rot, and wood-eating organisms.
In addition, it lasts longer whether placed inside or above the ground. Hence, you can use it for various applications.
How Long Does Pressure Treated Wood Last Outdoors?
Generally, outdoor furniture from pressure treated lumber lasts about twenty years. But this duration lengthens or shortens depending on where you live.
For instance, outdoor furniture in Phoenix, Arizona, lasts longer as the weather is always hot and dry.
On the other hand, due to frequent rains, you can expect the wood to have a shorter lifespan in Seattle, Washington.
Thankfully, you can extend the lumber’s life by storing it indoors during winter.
What Is CCA, and Why It’s Not Appropriate for Use in Outdoor Furniture?
CCA stands for Chromated Copper Arsenic and falls in the Chromated Arsenicals category.
The pesticide group protects the wood against termites, fungi, and other wood-destroying insects.
However, manufacturers stopped using CCA in all wood products after determining that it causes health issues.
In addition, the Environmental Protection Agency bans it for any residential applications.
CCA can quickly get into the body and cause different cancers. Besides, it can leach out of the treated lumber and cause health hazards.
Therefore, please avoid this wood for outdoor furniture.
Also, treat the wood with an oil-based stain to reduce CCA leaching for wood decks.
Can I get Sick From Burning Pressure Treated Wood?
Pressure treated materials are hazardous waste per the United States Environmental Protection Agency.
Moreover, burning treated lumber releases the chemical bond holding the arsenic. And one ash tablespoon contains a lethal poison dose.
You do not have to ingest the ash for the chemicals to harm you. Inhaling the microscopic chemicals cause a runny nose, burning eyes, and bronchitis.
Further, smaller wood particles can worsen asthma symptoms and trigger attacks.
Pressure treated lumber is not a casual issue due to the chemicals used. The primary concern is on preservative toxicity levels and the resulting health hazards.
Therefore, this guide helps us understand:
Allergic Reaction to Pressure Treated Wood
Sensitivity to the preservatives used in wood pressure treatment often results in allergic reactions.
Symptoms include skin rashes, hives, itching or burning sensations, red/watery eyes, sneezing, and a scratchy throat.
They can even be as severe as nausea, heart palpitations, chest pains, unconsciousness, wheezing, and a sudden blood pressure drop.