Press release correction.

This is a corrected version of Earthroots press releases sent out on June 13th, 2011.  It is important that you rely on this one and disregard previous versions.


Some Weyerhaeuser iLevel products contain formaldehyde, a chemical listed as “known to be a human carcinogen”


Studies indicate significant increased risk of hospitalization of children due to asthma correlated to formaldehyde exposure

Toronto - A chemical widely used in wood products mills has been newly found to cause cancer.  On Friday, June 10 2011, the U.S. government’s National Toxicology Program Report on Carcinogens listed formaldehyde as “known to be a human carcinogen” following a “rigorous scientific review;” a change from its previous listing as “reasonably anticipated to be a human carcinogen.”  The report found sufficient evidence from studies in humans that formaldehyde causes nasopharyngeal cancer, sinonasal cancer, and lymphohematopoietic cancer, specifically myeloid leukemia. [1] The U.S. Occupational Safety and Health Administration requires labeling for “all materials capable of releasing formaldehyde at levels above 0.5 ppm during normal use, the label must contain the words ‘potential cancer hazard’.” [2] The measurement unit parts per million is often abbreviated as ppm.

Formaldehyde-based resins are used to bind wood fibers in some forest products.  “In homes, the most significant sources of formaldehyde are likely to be pressed wood products made using adhesives that contain urea-formaldehyde (UF) resins.” [3] Phenol-Formaldehyde adhesives are used in some of Weyerhaeuser’s iLevel engineered wood products. [4] Products made with phenol-formaldehyde may emit formaldehyde, but generally at lower levels.

Weyerhaeuser reports in their iLevel Technical Resource Sheet that, "When tested in accordance with the ASTM large chamber test, formaldehyde emissions from these products were under 0.10 parts per million." [4] “This test method measures the formaldehyde concentration in air and emission rate from wood products containing formaldehyde under conditions designed to simulate product use.” [5] Weyerhaeuser does not state the exact emission levels in their iLevel Technical Resource Sheet nor in the Material Safety Data Sheets for iLevel products.

Health Canada reports that a scientific study indicated that formaldehyde levels “were significantly associated with hospitalization for asthma in children aged 6 months to 3 years, again after ruling out confounding from other indoor air pollutants.” A “significantly increased risk was observed at concentrations exceeding 60µg/m3.” [6] That level is equivalent to .049 ppm formaldehyde.  The results of another study, which pooled the results of seven published studies, “suggest a positive relationship between formaldehyde exposure and childhood asthma.” When “compared with individuals with no formaldehyde exposure, [children] with the highest levels of exposure reported in the seven studies (ie., 80 µg/m3) would have 3.5-times higher odds of asthma.”  [7] That level is equivalent to 0.065 ppm formaldehyde.

The Health Canada Guideline recommended maximum formaldehyde levels for indoor long term exposure is lower yet at 0.040 ppm. [8] The National Institute for Occupational Safety and Health (NIOSH) suggests that eight hour average exposure in the workplace be limited to much lower levels: 0.016 ppm.  [9] NIOSH is the U.S. federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness.

“Before you buy a home make sure to ask the builder if Weyerhaeuser iLevel products which have been made with phenol-formaldehyde resins are in the walls,” said David Sone of Earthroots.

The general population is exposed to formaldehyde by breathing contaminated indoor or outdoor air. [10] Health Canada reports that “On average, formaldehyde levels measured over a day in Canadian homes were 20-40 μg/m3 [.016-.0325 ppm]. Daily levels as high as 95 μg/m3 [.077 ppm], however, have been recorded.” [11]

Formaldehyde is released into the air from some mills that do not use formaldehyde based resins.  Weyerhaeuser reported releasing 3.1 tonnes of formaldehyde in on site air releases from their Kenora mill in the 2009 National Pollutant Release Inventory.  [12] According to Weyerhaeuser the formaldehyde emissions from the Kenora mill are not from resins, but rather from a natural occurrence where formaldehyde is released from the wood during the heating and drying process.


David Sone, Earthroots:  416-599-0152 x13



[1] Addendum to the 12th Report on Carcinogens Published by the U.S. Department of Health and Human Services, National Toxicology Program.  (June 11, 2011)

[2] Formaldehyde Fact Sheet.  Occupational Safety and Health Administration.  (April , 2011)

[3] An Introduction to Indoor Air Quality:  Formaldehyde.  United States Environmental Protection Agency.  Last updated on Tuesday, February 15, 2011.  Accessed June 20, 2011.

[4] Questions and answers about adhesives and formaldehyde emissions.  iLevel Weyerhaeuser Technical Resource Sheet. (November 2010)

[5] ASTM Standard E1333-10, "Standard Test Method for Determining Formaldehyde Concentrations in Air and Emission Rates from Wood Products Using a Large Chamber,” ASTM International, West Conshohocken, PA, 2010, DOI: 10.1520/E1333-10.

[6] Rumchev, K.B., Spickett, J.T., Bulsara, M.K., Phillips, M.R., and Stick, S.M. 2002. Domestic exposure to formaldehyde significantly increases the risk of asthma in young children. Eur. Respir. J. 20: 403-406. As cited in Health Canada Indoor Air Quality Guideline for formaldehyde (2006).

[7] McGwin G Jr., Lienert J, Kennedy JI Jr., 2009 Formaldehyde Exposure and Asthma in Children: A Systematic Review. Environ Health Perspect 118(3): doi:10.1289/ehp.0901143

[8] Health Canada Indoor Air Quality Guideline for formaldehyde (2006).

[9] Internation Chemical Safety Card for Formaldehyde.  National Institute for Occupational Safety and Health.  (October  2004)

[10] Formaldehyde Fact Sheet.  National Toxicology Program, National Institute of Environmental

[11] Formaldehyde - Pollutants from Household Products & Building Materials.  Health Canada website.  Page last modified August, 2010.  Accessed June 20, 2010.

[12] 2009 Facility On-Site Releases Weyerhaeuser Company Limited - Kenora Timberstrand.  Environment Canada National Pollutant Release Inventory.