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Chemical Sampling Information (CSI)
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General Description

Synonyms: Butaldehyde; Butanal; Butyl aldehyde

OSHA IMIS Code Number: B707

Chemical Abstracts Service (CAS) Registry Number: 123-72-8

NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: ES2275000

Department of Transportation Regulation Number (49 CFR 172.101) and Guide: 1129 129

Chemical Description and Physical Properties:
    colorless liquid with pungent odor
    molecular formula: C4H8O
    molecular weight: 72.12
    boiling point: 74.8°C
    vapor pressure: 12.2 kPa @ 20°C or 92 mm Hg @ 20°C
    melting point: -99°C
    flash point: -7°C

Exposure Limits

National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): Appendix C - Supplementary Exposure Limits

Health Factors

Potential Symptoms: Irritation of eyes, skin, respiratory tract; cough, sore throat; pulmonary edema (may be delayed); dizziness, lightheadedness; eye and skin pain, redness, burns (on contact with liquid); INGES. ACUTE: Burning sensation.

Health Effects: Irritation-Eyes, Nose, Throat, Skin---Marked (HE14); Pulmonary edema (HE4)

Affected Organs: Eyes, skin, respiratory system

  1. OSHA does not have a PEL for butyraldehyde.
  2. Vapor/air mixtures of butyraldehyde may be explosive.
  3. Butyraldehyde occurs naturally in some foods, such as white bread, beer, milk and potato chips, and it is listed by the FDA as a synthetic flavoring substance that is permitted for direct addition to food for human consumption (21 CFR 172.515).
  4. Like acetaldehyde, the metabolism of butyraldehyde (to butyric acid) is significantly decreased in liver preparations from individuals who are genetically heterozygous for the mutant form of aldehyde dehydrogenase-2.
  5. Butyraldehyde was one of several aldehydes that evoked erythema of the skin of volunteers when applied to the skin as a patch containing 25 µl of a 75% solution in water for five minutes.
  6. Inhalation toxicity studies in rats (6 hours/day, 5 days/week for 12-13 weeks) indicated increased relative kidney weights in males only at 50 ppm in the 12-week study, and altered blood parameters, lesions of the nasal epithelium, and mild interstitial pneumonia at 125 ppm (and higher) butyraldehyde in the 13-week study.
Date Last Revised: 02/22/2007

Literature Basis:
  • International Chemical Safety Cards (WHO/IPCS/ILO): Butyraldehyde.
  • No authors listed (NLM Toxline): Butyraldehyde: 9-day repeated vapor inhalation toxicity, vapor inhalation by dogs & rats for 12 & 13 wks, respectively & a 12-wk vapor inhalation study in rats with letter 020689 [Abstract]. EPA/OTS document #86-890000097.
  • Opdyke, D.L.: n-Butyraldehyde. Food Cosmet. Toxicol. 17: 731-734, 1979.
  • Pohanish, R.P. (editor): Butyraldehyde. In, Sittig’s Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 1. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 428-429.
  • Wang, R.-S., Nakajima, T., Kawamoto, T. and Honma, T.: Effects of aldehyde dehydrogenase-2 genetic polymorphisms on metabolism of structurally different aldehydes in human liver. Drug Metab. Dispos. 30(1): 69-73, 2002.
  • Wilkin, J.K. and Fortner, G.: Cutaneous vascular sensitivity to lower aliphatic alcohols and aldehydes in Orientals. Alcohol Clin. Exp. Res. 9(6): 522-525, 1985.

Monitoring Methods used by OSHA

Laboratory Sampling/Analytical Method:
  • sampling media: Coated XAD-2 Tube (150/75 mg sections, 20/60 mesh); coating is 10% (w/w) 2-(Hydroxymethyl)piperidine
    analytical solvent: Toluene
    maximum volume: 5 Liters
    maximum flow rate: 0.05 L/min
    current analytical method: Gas Chromatography; GC/NPD with GC/MS identification
    method reference: OSHA Modified NIOSH Analytical Method (NIOSH 2539) [255 KB PDF, 10 pages]
    method classification: Partially Validated
    note: OSHA modification is use of GC/NPD in place of GC/FID. This is a screening method and is not quantitative.

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Page last updated: 02/25/2008

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