Think of CDX plywood (C-D Exposure 1 Plywood), utility-grade plywood (E/F grade), and even reject plywood: these are the most economical grades plywood often used for structural purposes like subfloors, wall sheathing, roof decking, and general construction.
Cheap plywood is a popular choice for budget-friendly home projects, but its hidden dangers can pose health risks due to the potential release of formaldehyde, a known carcinogen, from the adhesives used to bond the wood layers.
While it’s cost-effective and suitable for a wide range of applications, the formaldehyde in cheap plywood—a naturally occurring organic compound—is released through the adhesives used in its production. Over time, these adhesives can off-gas formaldehyde into your home’s air, especially when the plywood is new or exposed to heat and humidity.
The health implications of exposure to formaldehyde can lead to various issues, depending on the concentration and duration of exposure. From toxic fumes to long-term risks, here’s what you need to know and how to protect your household.
1. Respiratory Issues: Irritation and Breathing Problems
Cheap plywood often uses urea-formaldehyde (UF) adhesives, which release formaldehyde gas into the air. Short-term exposure can irritate the eyes, nose, throat, and lungs, leading to coughing, wheezing, or difficulty breathing.
Why It Happens: UF resins off-gas more aggressively than pricier phenol-formaldehyde (PF) adhesives, especially in poorly ventilated spaces.
How to Avoid: Opt for CARB Phase 2-certified plywood which emits ≤0.05 ppm formaldehyde. It’s advisable to increase ventilation during installation and use air purifiers with activated carbon filters.
2. Skin and Eye Irritation
Direct contact with formaldehyde-emitting plywood dust or fumes can cause redness, itching, and rashes. Eye exposure may lead to watery eyes or blurred vision.
Why It Happens: Cutting or sanding cheap plywood releases particles and gases that irritate sensitive tissues.
How to Avoid: Wear protective gear like gloves and goggles when handling plywood. Alternatively, seal edges with low-VOC sealants to trap emissions.
3. Increased Cancer Risk
The World Health Organization (WHO) classifies formaldehyde as a Group 1 carcinogen, linked to nasal cancer and leukemia. Prolonged, high-level exposure for those in industrial settings or enclosed spaces poses the greatest threat. This is because cheap plywood emits higher formaldehyde concentrations, particularly in enclosed spaces.
How to Avoid: Choose exterior-grade plywood (PF-bonded) for lower emissions and avoid using cheap plywood in high-humidity areas like bathrooms, where off-gassing intensifies.
4. Aggravated Allergies and Asthma
Formaldehyde can trigger allergic reactions and worsen asthma symptoms, especially in children and sensitive individuals. Poorly regulated emissions from UF-bonded plywood linger in indoor air, acting as a persistent irritant.
How to Avoid: Prioritise E0-certified plywood whose formaldehyde levels do not exceed 0.05 mg/L. Besides, test indoor air quality with kits like Home Air Check to monitor formaldehyde levels.
5. Long-Term Chronic Health Effects
Chronic exposure to low-level formaldehyde may contribute to neurological issues, fatigue, and immune system suppression. This can be caused by cheap plywood in walls, cabinets, or furniture continuously releasing trace fumes over years.
How to Avoid: Replace old, deteriorating plywood with formaldehyde-free alternatives like bamboo or solid wood. Moreover, use air-purifying plants (e.g., spider plants, peace lilies) to absorb VOCs naturally.
In general, irritation of the eyes, nose, and throat; coughing; headaches; dizziness; and nausea are the short-term effects. While prolonged exposure to formaldehyde has been linked to certain types of cancer, such as nasopharyngeal cancer and leukemia.
Although these economical grades of plywood saves money upfront, its health costs can be steep. By investing in certified materials, improving ventilation, and choosing the right type of plywood, it not only affects appearance and durability, but also protects the indoor environment and human well-being.
