Wood Dust Exposure and Lung Cancer Risk

Exposure to wood dust is associated with lung cancer, but not all exposures are the same. While exposure on the job could be a problem, a hobby working with wood gives you a relatively low risk of cancer.

Hard woods from deciduous trees confer more risk than soft woods from evergreens, and geographic location may factor in as well. While wood dust is more strongly associated with nasopharyngeal carcinoma, people who are exposed to on-the-job wood dust or who work in occupations associated with the dust have elevated rates of lung cancer. Learn more about wood dust exposure, the current safety limits, and other medical conditions that are associated with wood dust exposure.

Wood Dust and Lung Cancer

Wood dust is one of the oldest occupational exposures known to man, and it's still very important today for people who work with cabinetry or in mills.

Occupational Risk and Lung Cancer

Lung cancer is a multifactorial disease with several risk factors. For example, asbestos exposure and smoking can cause lung cancer, and having both risks together further increases the likelihood of developing lung cancer.

So if you already have one or more risk factors for lung cancer, it makes sense to avoid wood dust exposure, which might add to your risk.

Wood Dust as a Carcinogen

Wood dust is considered a Group I carcinogen, a substance known to cause cancer in humans. Wood dust is made up of a conglomeration of different substances derived from hardwood or softwood trees.

Hard Woods vs. Soft Woods

Several of the studies on wood dust and lung cancer distinguish between softwood dust and hardwood dust, with hardwood dust being significantly more likely to cause cancer.

But what constitutes hardwood and what are softwoods?

• Hardwoods are deciduous trees that lose their leaves in the fall. Wood from some hardwood trees is actually very soft, such as birch and balsa.
• Softwoods are coniferous trees that do not lose their leaves but remain green year-round (evergreens).

Research on Wood Dust and Cancer

Many studies have looked at the relationship between wood dust and cancer. A 2015 review of 70 studies found that the strongest link between wood dust and cancer is the risk of nasal adenocarcinoma (a head and neck cancer). Overall, it was found that there is low to moderate evidence that wood dust can lead to lung cancer as well.

• A different 2015 review of 10 studies found a significantly increased risk of lung cancer with wood dust exposure; those who were exposed to wood dust were at least 20% more likely to develop the disease, and those who worked in wood dust-associated occupations had a 15% greater risk. In contrast, a slightly reduced risk of lung cancer was noted in people in Nordic countries who were exposed to primarily softwood dust. The authors concluded that the risk may be dependent on geographic location and the type of wood dust exposure.
• Another study out of Canada found the risk of lung cancer related to wood dust exposure was increased by approximately around 40%. The most common occupations linked with exposure were construction work, timber, and furniture making. An important point in this study is that substantial exposure over a lengthy period of time was necessary to increase cancer risk, and there was little risk among those whose cumulative exposure was not substantial. This may be of some reassurance to those who enjoy woodworking as a hobby.

Other Related Medical Conditions

Wood dust has long been known to lead to medical conditions other than cancer. These include:

Skin Rashes (Dermatitis)

Skin rashes related to wood dust are common and have been found with exposure to dust from over 300 different types of trees. The rashes, itching, and redness can arise due to skin irritation or from allergic reactions.

Respiratory Allergies

Allergic reactions such as allergic asthma are common with wood dust exposure. The best-known reaction is a reaction to red cedar, to which 5% of workers are allergic. Wood dust is considered one of the top 10 causes of occupational asthma in the U.K.

Respiratory Symptoms Unrelated to Allergies

Nasal symptoms, such as itching, dryness, coughing, wheezing, and repeated episodes of sinusitis are linked to wood dust exposure.

Decreased Lung Function

Though noted more with softwoods, exposure to wood dust may result in decreased pulmonary function. In addition, exposure to wood dust can disrupt the cilia, the small hair-like structures in the respiratory tree that remove inhaled toxins from the airways.

Recommended Limits for Exposure

OSHA recommends an eight-hour exposure limit of 5 mg/m3 for hard wood and soft wood.

An exception is red cedar wood dust, for which the eight-hour limit is 2.5 mg/m3 due to its potential to cause allergic reactions.

Occupations at Risk

Occupations that result in high wood dust exposure include:

• Carpenters
• Pulp and paper mill workers
• Furniture workers
• Cabinetmakers
• Sawmill workers
• Sander operators, press operators, and lithe operators

Using machinery to manipulate wood results in the highest exposure. This includes chipping, sanding, drilling, and shaping.

Hazards and Precautions

In addition to following the limits for eight-hour exposure to wood dust, there are many things that employers and employees can do to minimize exposure.

Some basic recommendations include:

• Consider industrial ventilation systems and high-efficiency HEPA filters in the workplace
• Wearing a respirator (masks provide little if any protection and could give false assurance that you are not at risk)
• Wet clean up is preferred to dry clean up, and air blowers should never be used to clean up wood dust
• Keep machine parts sharp and in good repair, as dull blades can result in more wood dust
• Keep in mind that people who clean and maintain woodworking equipment are also at risk

Check out OSHA's information covering potential hazards and possible solutions with regard to on-the-job wood dust exposure to learn about ways to reduce the amount of wood dust you inhale at work.

Other Potential Exposures in Wood Working

It's important to note that people who work with wood can also have exposure to other toxic substances. Chemicals such as glue and varnishes can also be a risk factor for cancer.

Make sure to read the Material Data Safety Sheets on all substances you are exposed to at work.

What About Your Woodworking Hobby?

In studies thus far, exposure to wood dust as a hobby was not found to be linked with lung cancer. Even with occupational exposure, research suggests that the exposure needed to be "cumulative and substantial" to increase the risk of cancer.

That said, always practice good ventilation while working with wood and with any chemicals. Always read labels and follow the recommendations. If a label recommends using gloves or a mask, heed those instructions.

A Word From Verywell

It can be discouraging as you consider cancer risks with specific exposures. You may catch yourself saying, "Doesn't everything cause cancer?" Yet, learning about these risks, and taking action, doesn't mean that you need to become a fanatic. There are often very simple measures you can take to reduce your risk.

Employers now have guidelines that specify the quantity and amount of time that a person may be exposed to wood dust without raising the risk of cancer. That said, it is important for employees to be aware of these guidelines and follow them, and to speak up if appropriate attention to these limits is not followed in their place of work.

Whether or not you are exposed to wood dust, take the time to check out these tips for lowering your risk of lung cancer. Lung cancer is the leading cause of cancer-related deaths for both men and women and lung cancer in never-smokers is the 6th leading cause of cancer-related deaths in the United States.