Wood Dust: Known Human Carcinogen
Wood dust is known to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in humans. First Listed in the Tenth Report on Carcinogens (2002). An association between wood dust exposure and cancer of the nasal cavity has been observed in many case reports, cohort studies, and case-control studies that specifically addressed nasal cancer.
The National Institute for Occupational Safety and Health (NIOSH) considers both hardwood and softwood dust to be potentially carcinogenic and provides guidance on specific wood dust exposure limits. The primary types of cancers associated with wood dust exposure are nasal and sinus cavity cancer, lung cancer, and Hodgkin's disease. Not too surprisingly, those most at risk are workers in mills, furniture plants, cabinet makers, and carpenters. That is, people who spend a significant amount of time around wood and wood dust. The association between occupational exposure to wood dust and various forms of cancer has been investigated in many studies and in many countries. Note that in 1987, the International Agency for Research on Cancer (IARC) classified furniture manufacturing in Category I (confirmed human carcinogen) and carpentry in Category 2B (suspected human carcinogen).
Exposure to wood dust has long been associated with a variety of adverse health effects, including dermatitis, allergic respiratory effects, mucosal and nonallergic respiratory effects, and cancer. Contact with the irritant compounds in wood sap can cause dermatitis and other allergic reactions. The respiratory effects of wood dust exposure include asthma, hypersensitivity pneumonitis, and chronic bronchitis.
- Both the skin and respiratory system can become sensitized to wood dust. When a worker becomes sensitized to wood dust, he or she can suffer severe allergic reactions (such as asthma or dermatitis) after repeated exposure or exposure to lower concentrations of the dust.
- Other common symptoms associated with wood dust exposure include skin and eye irritation; nasal dryness and obstruction; and prolonged colds.
- The OSHA permissible exposure limit for nuisance dust is 15 mg/m3 , total dust (5 mg/m3, respirable fraction) 8 hour time weighted average. NIOSH has set a recommended exposure level of 1 mg/m3 total dust. The ACGIH has recommended a 0.5 mg/m3Threshold Limit Value for western red cedar based on its asthma effects. Certain species of hardwood — such as oak, mahogany, beech, walnut, birch, elm, and ash — have been reported to cause nasal cancer in woodworkers. This is particularly true when exposures are high.