Chemical Analyses Warn: Pallet Furniture May Contain Toxic Substances

In recent years, furniture made from wooden pallets—whether for gardens or homes—has gained significant popularity. The reason is clear: pallets are inexpensive, widely available, environmentally recyclable, and aesthetically appealing. However, few people realize that not all pallets are safe for home or garden use - primarily due to the chemical treatments they undergo for international shipping. What chemicals are used in treating pallets? What effects do they have? Watrex Praha has prepared an article to help you recognize potentially dangerous ones.

Watrex Praha: Chemical Analyses Warn: Pallet Furniture May Contain Toxic Substances

At first glance, pallets may appear to be simple wooden materials. In reality, it’s more complicated. Pallets primarily serve as transport packaging that must withstand mold, insects, moisture, and chemical sprays. To ensure hygiene during international transport, they are subject to the ISPM 15 standard, which dictates the treatment of the wood: either heat treatment (HT) or fumigation with methyl bromide (MB). The latter can leave harmful chemical residues in the wood.

Chemicals Used in Pallet Treatment 

One of the most problematic substances is methyl bromide (MB), a pesticide previously used extensively. It is neurotoxic and negatively affects the respiratory system, eyes, and nervous system. It has long been banned in the EU, but older pallets may still contain it. In addition, pallets may be contaminated by other chemicals absorbed during the transport of industrial materials or liquid products. Contamination can be localized (e.g., oil stains) or widespread due to the absorption of volatile substances. 

Toxicology: 

• Neurotoxic: Affects the central nervous system, may cause headaches, seizures, confusion, and in extreme cases, death. 
• Mutagenic and Carcinogenic: Long-term exposure is suspected of genotoxic effects. 
• Ecotoxic: A potent greenhouse gas and ozone-depleting substance (banned by the Montreal Protocol). 

Important! 

Pallets marked with the code "MB" (e.g., “HT DB MB”) should not be considered safe —the wood may still contain methyl bromide residues.

Formaldehyde, Toluene, and Heavy Metals 

Used pallets may be painted with coatings that pose additional risks (allergic reactions, skin and mucous membrane irritation, chronic health problems from prolonged exposure, and release of volatile organic compounds).

Watrex Praha: Chemical Analyses Warn: Pallet Furniture May Contain Toxic Substances

Formaldehyde 

Formaldehyde is a simple aldehyde found in many materials used in furniture production. In pallets, it may be present due to industrial paints, adhesives, or preservatives. It is a pungent-smelling gas and a proven carcinogen (IARC Group 1). It is released at room temperature and prolonged exposure can cause mucosal irritation, headaches, asthma symptoms, and, in extreme cases, neurological disorders.

Toluene 

Toluene is an aromatic hydrocarbon commonly found in glues, paints, and solvents. It may enter pallets through chemical cargo or surface treatments. Inhalation affects the central nervous system: short-term exposure may cause euphoria, drowsiness, and disorientation; long-term exposure can impair memory, concentration, and behavior.

Heavy Metals

Heavy metals such as lead, cadmium, or chromium may be present in pallets due to old industrial coatings. These metals are persistent and toxic: lead damages the nervous system, cadmium accumulates in the kidneys and is carcinogenic, and chromium (especially Cr VI) is highly irritating and toxic. The danger lies in their release into dust or food when in contact with pallet wood. 

How to Recognize a Safe Pallet 

The key indicator is the marking according to ISPM 15. Look for burned-in or stamped codes:

Watrex Praha: How to recognize a safe pallet

Pallets that are unmarked, heavily soiled, painted with unknown substances, or have a strong chemical odor are **not** suitable for furniture making. Ideally, a pallet should be clean, dry, unpainted, and marked “HT.” 

Summary for DIYers and Designers 

• Use only pallets marked “HT.” 
• Avoid unmarked pallets or those with obvious stains, oil spots, or paint.
• Before use: 
  • Thoroughly clean and sand the pallet, 
  • Treat it with an eco-friendly varnish or wax suitable for indoor/outdoor use. 

Conclusion 

Pallet furniture can be a beautiful and eco-friendly solution - if you pay attention to the origin and treatment of the wood. Chemicals used in the transport of wooden pallets pose a real risk—to both human health and the environment. Awareness of pallet markings and their treatments is the key to safe home use. So next time you’re sanding down a pallet, make sure you know what you’re working with. 

For more interesting information, visit our website www.watrex.com.