In 2009 wood dust was added to the California Proposition 65 (Safe Drinking Water and Toxic Enforcement Act of 1986) list of chemicals known to the State of California to cause cancer. More recently, additional chemicals associated with wood products, Titanium Dioxide in 2011 and naturally occurring wood Methanol in 2012, have been added to the Prop 65 list of chemicals known to the state of California to cause cancer or reproductive harm.
Wood products will expose individuals to wood dust when they are drilled, sawn, sanded, machined, or otherwise handled in a manner that will produce wood dust. Titanium dioxide is a chemical that is sometimes used in edge and end sealers in engineered wood and lumber products, wood stencil paints and inks as a color brightener. Not all ink, paint and sealer formulations used on wood products contain TiO2 and the presence of the chemical varies across individual product lines by manufacturers.
According to the California Office of Environmental Health Hazard Assessment (OEHHA), the Titanium Dioxide listing is for airborne particles of respirable size and does not cover TiO2 when it remains bound within a product matrix. Consumer exposure to respirable TiO2 would occur only when a wood product is sawn, sanded or machined in an area of the product that contained a (TiO2) sealer, stencil or similar coating.
In 2013, Methanol that naturally occurs in the biodegradation of wood products was added to consumer warning materials. Methanol was listed as a chemical known to cause birth defects or reproductive harm under Proposition 65, effective March 16, 2012. Methanol, sometimes called “wood alcohol”, occurs naturally at low levels in wood, fruits, vegetables and many common foods. Methanol is also produced naturally in the anaerobic metabolism of many varieties of bacteria, and is commonly present in small amounts in the environment. Methanol’s main use is in the production of chemicals.
OEHHA has established two “maximum allowable dose levels” that identify levels of exposure to Methanol that require warnings and prohibit discharges to sources of drinking water. The maximum exposure level for Methanol emissions from wood products is 47,000 micrograms per day for inhalation.
As a result, wood products manufacturers are providing a clear and reasonable warning to consumers about the potential hazard of wood dust and wood related chemicals prior to purchasing their products. These manufacturers are informing their distributors, including wholesalers and retailers, of their duty to provide the warnings to consumers.
Per the requirements of Proposition 65, any purchasers of lumber or wood products should be aware of the following:
WARNING: Drilling, sawing, sanding or machining wood products generates wood dust and other substances known to the State of California to cause cancer. Avoid inhaling dust generated from wood products or use a dust mask or other safeguards to avoid inhaling dust generated from wood products.
Wood products emit chemicals known to the State of California to cause birth defects or other reproductive harm.
California Health and Safety Code Section 25249.6This warning also may be shown in invoices or other documentation related to the sale of lumber and other wood products.