CASRN 50-00-0 | DTXSID7020637

Noncancer Assessment

Reference Dose for Oral Exposure (RfD) (PDF) (17 pp, 133 K) Last Updated: 09/01/1990

System RfD (mg/kg-day) Basis PoD Composite UF Confidence
Urinary, Gastrointestinal, Other 2 x 10-1 Reduced weight gain, histopathology in rats NOAEL : 1.5 x 101
100 Medium


Reference Concentration for Inhalation Exposure (RfC) (PDF) (17 pp, 133 K)
Not assessed under the IRIS Program.


Cancer Assessment

Weight of Evidence for Cancer (PDF) (17 pp, 133 K) Last Updated: 05/01/1991

WOE Characterization Framework for WOE Characterization
B1 (Probable human carcinogen - based on limited evidence of carcinogenicity in humans) Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1986)
  • Based on limited evidence in humans, and sufficient evidence in animals. Human data include nine studies that show statistically significant associations between site-specific respiratory neoplasms and exposure to formaldehyde or formaldehyde-containing products. An increased incidence of nasal squamous cell carcinomas was observed in long-term inhalation studies in rats and in mice. The classification is supported by in vitro genotoxicity data and formaldehyde's structural relationships to other carcinogenic aldehydes such as acetaldehyde.
  • This may be a synopsis of the full weight-of-evidence narrative.

Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (17 pp, 133 K)

Not Assessed under the IRIS Program.

Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (17 pp, 133 K)

Inhalation Unit Risk: 1.3 x 10 -5 per µg/m3
Extrapolation Method: Linearized multistage procedure, additional risk
Tumor site(s): Respiratory
Tumor type(s): Squamous cell carcinoma (Kerns et al., 1983)

Additional EPA toxicity information may be available by visiting the following sites:

Note: The formaldehyde (re)assessment was suspended in Dec 2018, but may be restarted as Agency priorities change.

Assessment Manager(s): James Avery (

Step Assessment Materials Released to the Public Release Date Public Meeting Date
4 Peer Review Draft 06/2010 05/2011
  Suspended 12/2018  

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