Formaldehyde malignancies

Selected Case-Control Studies. Luce et al. (1993b) attempted to detennine whether occupational exposure to fonnaldehyde was associated with an increased risk of sinonasal cancer in humans. Case subjects were patients with primary malignancies of the nasal and paranasal sinuses. Odds ratios for squamous cell carcinomas in formaldehyde-exposed workers, when adjusted for wood dust and glue exposure, were not significantly elevated. The odds ratio for adenocarcinomas was confounded by the frequent co-exposure to wood dust, a known carcinogen. However, in those exposed to wood dust, an increased odds ratio was noted in those also exposed to formaldehyde. The authors concluded that the data did not support an increased risk of nasal cancers due to formaldehyde alone. 

Animal Cancer Studies As discussed previously in Section 2.2.1.2 subsection entitled Chronic Inhalation Animal Studies, chronic exposure to airborne formaldehyde concentrations ranging from about 6 ppm to 15 ppm induced increased incidences of nasal tumors (squamous cell carcinomas, squamous cell papillomas, or polyploid adenomas) in three bioassays with Fisher 344 rats (Kamata et al. 1997 Kems et al. 1983b Monticello et al. 1996 Swenberg et al. 1980). Increased incidences of lower respiratory tract tumors or distant site tumors were not found in these studies, and exposure to concentrations of 2 ppm and lower induced no malignant nasal tumors. 

Studies of animals exposed for life to formaldehyde in air or drinking water also show that formaldehyde primarily damages tissue at portals-of-entry (i.e., the upper respiratory tract and the gastrointestinal tract) evidence for toxic effects at distant sites is less consistent. Replicated inhalation studies have shown that formaldehyde induced malignant nasal tumors in rats at high exposure concentrations (10-15 ppm) that also induced nasal epithelial necrosis and cellular proliferation, but not at lower concentrations (0.3-2 ppm) that did not markedly damage nasal epithelial tissue (Albert et al. 1982 ... 

Holmstrom M, Lund VJ. 1991. Malignant melanomas of the nasal cavity after occupational exposure to formaldehyde. Br J Ind Med 48 9-11. 

Hauptmann M, Stewart PA, Lubin JH, Beane Freeman LE, Hornung RW, Herrick RF, Hoover RN, Fraumeni JF, Blair A, Hayes RB. Mortality from lymphohematopoietic malignancies and brain cancer among embalmers exposed to formaldehyde. J Natl Cancer Inst 2009 101(24) 1696-708. 

Checkoway H, Boffetta P, Mundt DJ, Mundt K. Critical review and synthesis of the epidemiologic evidence on formaldehyde exposure and risk of leukemia and other lymphohematopoietic malignancies. Cancer Causes Control 2012 23(ll) 1747-66. 

Freeman, L.E.B., Blair, A., Lubin, J.H., Stewart, P.A., Hayes, R.B., Hoover, R.N., Hauptmann, M. Mortality from lymphohematopoietic malignancies among workers in formaldehyde industries the National Cancer Institute Cohort. J. Natl. Cancer Inst. 101(10), 751-761 (2009)... 

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