Wood allergies and toxicity – FineWoodworking

overview: As many woodworkers know, some woods can cause an irritating reaction on the skin. That’s because of compounds called extractants that work against pests and spoilage. Reactions to these compounds range from mild to extreme depending on your personal makeup, so it makes sense to do some research on the wood you plan to use. Here we look at common woods and where they fall on a scale from benign to allergenic to toxic.

Wood contains specific compounds, called extractants, that range from harmless to all humans, to allergenic to some, to acutely toxic to all. Hypersensitivity and allergy can be tolerated to some extent, but toxicity can lead to organ failure and death in the most extreme cases. This article explores the science and terminology associated with these bioactive compounds in wood, identifies their adverse effects, and explains how to mitigate them.

Complicating matters, different people respond differently to the same compounds, making it difficult to tell whether the wood is toxic or simply irritating. Also, many forests have limited human studies, so in some cases conclusions can only be drawn from animal experiments and anecdotal evidence.

When it comes to allergies and toxicity, wood scientists like me mostly talk about end uses, especially skin contact and ingestion rather than inhaling the dust during manufacturing. But anything that causes problems when touched or ingested can be inhaled into the respiratory tract and lungs, as dust with a much larger surface area to transport dangerous compounds presents an even more serious problem. Locomotion is more effective in a warm, moist environment.

It should be noted that wood dust, regardless of type, is a known carcinogen, so it is important for all woodworkers to collect wood dust at its source and properly filter it. It means that

due to the extract Trees store nutrients in stacked photocells that radiate out from the center of the trunk. As the sapwood transforms into heartwood, excess nutrients are converted into extracts that help prevent pests and rot, especially important in moist tropical environments.

Understand basic terminology

It can be a little confusing, but let’s start with the types of people’s reactions to trees. The first type is sensitivity. Some medical literature defines hypersensitivity as a reaction without an immune response, while others define hypersensitivity as a delayed immune response.

In fact, susceptibility is a catch-all term used when a person is reacting but the reason for it cannot be determined. For example, many people who report side effects to gluten do not have celiac disease, IBS, or other known causes.

Diagnosing hypersensitivity is difficult or impossible, so we focus on quantifiable reactions: allergy and toxicity.

Allergies vary from person to person

Allergies are histamine reactions. Humans can be allergic to virtually anything, from peanuts and pollen to dust and dander. And allergic reactions tend to be caused by multiple contacts. For example, the first time you handle Eastern Red Cedar, you may not react, but the second time you may experience hives. This process of increasing allergy to a compound over time is known as “sensitization” (not to be confused with hypersensitivity). Wood contains many compounds that can increase allergic reactions over time, especially aromatic woods such as cedar. Whether a person responds to the first and his fifth exposure is a product of a person’s unique biology.

When you’re allergic to something, the body’s reaction can mimic a toxic reaction, so for many applications allergens should be treated like toxic compounds.

Toxicity is universal

The term toxic indicates that all humans react similarly to the compound. If all woodworkers sneezed in the presence of cedar, it would be considered not only an allergen, but poisonous. Toxic reactions range from drowsiness, contact dermatitis, urticaria, respiratory illness to genotoxicity (potential to damage DNA and chromosomes that may be inherited).

There are some toxic compounds released from wood, such as sassafras safrole. Although raw wood is not currently regulated by the FDA, some of these released compounds are. Therefore, it becomes easier to find information about them.

— Dr. Ceri Robinson is a professor of wood anatomy, an avid woodturner, and the author of numerous books on turning, spalting, and wood technology.

Photos unless otherwise stated: Staff.

For more photos and information, “View PDF” Buttons below:

from fine woodwork #304

View PDF