Health Hazzards

Like many other plants, trees produce antibiotic chemicals to protect themselves from the organisms that cause disease and decay. These may also have an unpleasant effect on craftsmen who come in intimate contact with the wood.

WOOD-RELATED AILMENTS

Chemicals in wood have been found to cause or contribute to:

  • Nausea and headaches
  • Kidney and liver malfunction
  • Skin rashes and eye irritation
  • Asthma, emphysema, and other respiratory problems
  • Nasal cancer

This can be a problem for craftsmen, but it shouldn’t be blown out of proportion. Not everyone is affected by the potentially toxic chemicals in wood. Only 2 to 5 people out of 100 develop an unhealthy sensitivity to them, although woodworkers have an increased risk. And not many woods contain enough chemicals to be dangerous. There are just a few troublesome species, listed in the chart below.

Nick wearing positive-pressure face mask

I've found that the most effective and comfortable way to protect myself from sawdust (especially during dust-intensive tasks like sanding) is to wear a positive-pressure face mask. A fan blows filtered air over my face at all times. The air leaks out around the edges of the mask, preventing sawdust from entering. This is an older model with the fan, filter, and batteries in a fanny-pack. Newer units incorporate the filter and fan – sometimes even the batteries – in the helmet. There are are also effective positive-pressure "partial" masks that look very much like ordinary dust masks.*

IRRITANTS AND SENSITIZERS

There are two common ways that a wood may affect your health — as either an irritant or a sensitizer. Irritants bother most craftsmen, at least to a small degree. These effects may be mechanical rather than chemical — fine sawdust tickles your nasal passages and makes you sneeze. More often, though, it’s the chemicals in the sawdust that irritate you. The tannic acid in oak, for example, is a powerful irritant.

Sensitizers affect only those people who are allergic to them. Allergic reactions range from a runny nose and watery eyes to hives and asthma. Furthermore, repeated exposure often causes greater sensitivity, and the reaction becomes more severe.

A very few woods contain chemicals which cause systemic reactions, affecting the stomach, nerves, kidneys, even the heart. Oleander and yew, for example, contain chemicals similar to digitalis, a heart drug.

LIMITING EXPOSURE

What can you do to limit your exposure? Quite a bit.

  • Wear a dust mask. The most common way you get wood chemicals into your body is by inhaling them.
  • Use a dust collector when running power tools.
  • Ventilate your shop and clean it frequently.
  • Keep your shop cool. Heat causes you to perspire. This mixes with sawdust and releases more toxic chemicals.

Just as important, you should not expose other people. Never use potentially toxic woods to make cutting boards, bowls, or eating utensils. Also avoid them for toys, jewelry, and items that someone might put in their mouth or rub against their skin.

One more precaution: See a doctor if you have recurrent nosebleeds or persistent sinus infections when you work wood. These are causes for special concern.

Glossary of Terms

  • Irritation –The wood species acts as an irritant, causing itching, rashes, watery eyes, and other uncomfortable reactions.
  • Sensitivity – The wood species acts as a sensitizer, causing people to develop allergic reactions after repeated exposure.
  • Direct toxicity – Chemicals (called extractives) in the wood species are poisonous.
  • Nausea, malaise – Exposure to the wood species cause flu-like symptoms.
  • Systemic – Reactions are not confined to a specific body part; they affect much or most of the biologic system.
  • Nasopharyngeal cancer – A cancer that affects the back of the throat where the nasal passages open into it.

Toxic Woods and How They Affect You

Wood Species Reaction Part of Body Potency Source Occurrence
Bald Cypress Sensitivity Respiratory + Dust Rare
Balsam Fir Sensitivity Eyes, Respiratory + Leaves, Bark Common
Beech Sensitivity, Nasopharyngeal Cancer Eyes, Skin, Nose, Throat ++ Dust, Leaves, Bark Common, Unknown
Birch Sensitivity Respiratory ++ Dust, Wood Common
Black Locust Irritation Eyes, Skin +++ Leaves, Bark Common
Blackwood Sensitivity Eyes, Skin ++ Dust, Wood Common
Boxwood Sensitivity Eyes, Skin ++ Dust, Wood Common
Cashew Sensitivity Eyes, Skin +++ Dust Common
Cocobolo Sensitivity, Irritation Eyes, Skin, Respiratory +++ Dust, Wood Common
Dahoma Irritation Eyes, Skin ++ Dust, Wood Common
Ebony Sensitivity, Irritation Eyes, Skin ++ Dust, Wood Common
Elm, Red Irritation Eyes, Skin + Dust Rare
Goncalo Alves Sensitivity Eyes, Skin ++ Dust, Wood Rare
Greenheart Sensitivity Eyes, Skin ++ Dust, Wood Common
Blackwood (Surinam) Sensitivity Eyes, Skin +++ Dust, Wood Common
Hemlock Nasopharyngeal Cancer Respiratory ? Dust Unknown
Iroko Sensitivity, Irritation, Pneumonitis, Alveolitis Eyes, Skin, Respiratory +++ Dust, Wood Common
Mahogany, Honduras Sensitivity, Pneumonitis, Alveolitis Skin, Respiratory + Dust Unknown
Mansonia Sensitivity, Irritation, Nausea, Malaise Eyes, Skin, Systemic +++ Dust, Wood Common
Maple (Spalted) Sensitivity, Pneumonitis, Alveolitis Respiratory +++ Dust (contains mold) Common
Mimosa Nausea, Malaise Systemic ? Leaves, Bark Unknown
Myrtle Sensitivity Respiratory ++ Dust, Leaves, Bark Common
Oak Sensitivity, Nasopharyngeal Cancer Eyes, Skin, Nose, Throat ++ Dust, Leaves, Bark Rare
Obeche Sensitivity, Irritation Eyes, Skin, Respiratory ? Dust, Wood Common
Oleander Direct Toxicity, Nausea, Malaise, Cancer Systemic ++++ Dust, Wood, Leaves, Bark Common
Olivewood Sensitivity, Irritation Eyes, Skin, Respiratory +++ Dust, Wood Common
Opepe Sensitivity Respiratory + Dust Rare
Padauk Sensitivity, Nausea, Malaise Eyes, Skin, Systemic + Dust, Wood Rare
Pau Ferro Sensitivity Eyes, Skin + Dust, Wood Rare
Peroba Rosa Irritation, Nausea, Malaise Respiratory, Systemic ++ Dust, Wood Unknown
Purpleheart Nausea, Malaise Systemic ++ Dust, Wood Common
Quebracho Irritation, Nausea, Malaise, Nasopharyngeal Cancer Respiratory, Systemic, Nose, Throat ++ Dust, Bark, Leaves Common
Redwood Sensitivity, Pneumonitis, Alveolitis, Nasopharyngeal Cancer Eyes, Skin, Respiratory ++ Dust Rare
Rosewoods Sensitivity, Irritation Eyes, Skin, Respiratory ++++ Dust, Wood Common
Satinwood Irritation Eyes, Skin, Respiratory +++ Dust, Wood Common
Sassafras Sensitivity, Direct Toxicity, Nausea, Malaise, Nasopharyngeal Cancer Respiratory, Systemic, Nose, Throat + Dust, Wood, Leaves, Bark Rare
Sequoia Irritation Respiratory + Dust Rare
Snakewood Irritation Respiratory ++ Dust, Wood Rare
Spruce Sensitivity Respiratory + Dust, Wood Rare
Walnut Sensitivity Eyes, Skin ++ Dust, Wood Common
Wenge Sensitivity Eyes, Skin, Respiratory ++ Dust, Wood Common
Willow Sensitivity, Nausea, Malaise Respiratory, Systemic + Dust, Wood, Leaves, Bark Unknown
Western Red Cedar Sensitivity Respiratory +++ Dust, Leaves, Bark Common
Teak Sensitivity, Pneumonitis, Alveolitis Eyes, Skin, Respiratory ++ Dust Common
Yew Irritation, Direct Toxicity, Nausea, Malaise, Nasopharyngeal Cancer Eyes, Skin, Systemic, Nose, Throat ++++ Dust, Wood Common
Zebrawood Sensitivity Eyes, Skin ++ Dust, Wood Rare

Note: The information in this chart is based on data collected by Robert Woodcock, RN, BSN, CEN

chisel edge geometry

Back to Top