- Synonyms: Artificial almond oil; Benzene Carbaldehyde; Benzenecarbonal; Benzoic Aldehyde; Phenylmethanal
- OSHA IMIS Code Number: B105
- Chemical Abstracts Service (CAS) Registry Number: 100-52-7
- NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: CU4375000
- Department of Transportation Regulation Number (49 CFR 172.101) and Guide: 1990 129
- Chemical Description and Physical Properties:
- colorless to yellow liquid with a characteristic odor of almonds
- molecular weight: 106.13
- vapor pressure: 133 Pa @ 26°C or 1 mm Hg @ 20°C
- molecular formula: C7H6O
- boiling point: 179°C
- melting point: -26°C
- Incompatibilities: Reacts violently with aluminium, bases, iron, oxidants and phenol causing fire and explosion hazard.
- Potential Symptoms: Irritation of eyes, skin, nose, throat; contact dermatitis; INGES. ACUTE: sore throat
- Health Effects: Irritation-Eyes, Nose, Throat, Skin---Moderate (HE15)
- Affected Organs: Eyes, skin, respiratory system
- OSHA does not have a PEL for benzaldehyde. It may be absorbed through the skin.
- Vapor/air mixtures of benzaldehyde may be explosive above 63°C.
- Benzaldehyde is listed by the FDA as a synthetic flavoring substance that is generally recognized as safe (GRAS) for its intended use (21 CFR 182.60). It also is an authorized denaturant for specially denatured alcohol (27 CFR 21.151).
- Benzaldehyde is metabolized to benzoic acid by aldehyde oxidase and by aldehyde dehydrogenase. Its major metabolite in urine is hippuric acid (benzoylglycine). Unlike acetaldehyde, the metabolism of benzaldehyde by aldehyde dehydrogenase-2 appears to be largely unaffected by genetic polymorphism.
- Subacute inhalation studies in rats at 500, 750 and 1000 ppm indicated hypothermia and other CNS effects at all doses, with abnormal gait, severe tremors, and convulsions occurring at the highest concentration. Female rats were more susceptible to the lethal effects of 750 and 1000 ppm benzaldehyde, whereas males showed a higher incidence of goblet cell metaplasia of the respiratory epithelium in the nasal septum, which did not differ in severity between the 500 and 1000 ppm groups after 14 days of 6-hr/d exposures.
- Benzaldehyde was reported to be allergenic in guinea pigs in the Draize test, the maximization test, and a test with Freud’s complete adjuvant. Nine of 26 employees at a perfume factory had positive patch tests with benzaldehyde (5% in petrolatum).
- Mice, but not rats, showed increased incidences of squamous cell papillomas and hyperplasia of the forestomach in 2-year carcinogenicity studies of benzaldehyde administered by oral gavage. A Cosmetic Ingredient Review Expert Panel considered benzaldehyde to not be a carcinogenic risk to humans.
- Literature Basis:
- International Chemical Safety Cards (WHO/IPCS/ILO): Benzaldehyde.
- Al-Salmy, H.S.: Individual variation in hepatic aldehyde oxidase activity. IUBMB Life 51(4): 249-253, 2001.
- Andersen, A.: Final report on the safety assessment of benzaldehyde. Int. J. Toxicol. 25(Suppl. 1): 11-27, 2006.
- Lahan, S., Broxup, B., Robinet, M., Potvin, M. and Schrader, K.: Subacute inhalation toxicity of benzaldehyde in the Sprague-Dawley rat. Am. Ind. Hyg. Assoc. J. 52(12): 503-510, 1991.
- No authors: NTP toxicology and carcinogenesis studies of benzaldehyde (CAS No. 100-52-7) in F344/N rats and B6C3F1 mice (Gavage Studies). Natl. Toxicol. Program Tech. Rep. Ser. (514): 1-191, 2004.
- Pohanish, R.P. (editor): Benzaldehyde. In, Sittig’s Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 1. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 305-306.
- Santisteban, I., Povey, S., West, L.F., Parrington, J.M. and Hopkinson, D.A.: Chromosome assignment, biochemical and immunological studies on a human aldehyde dehydrogenase, ALDH3. Ann. Hum. Genet. 49(Pt. 2): 87-100, 1985.
- Schubert, H.-J.: Skin diseases in workers at a perfume factory. Contact Dermatitis 55(2): 81-83, 2006.
- 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.
- Date Last Revised: 01/29/2007
Monitoring Methods used by OSHA
Primary Laboratory Sampling/Analytical Method (SLC1):
- Two Coated Glass Fiber Filters (Open Face) in one cassette separated by a spacer. The filters are coated with 2,4-Dinitrophenylhydrazine (DNPH) and Phosphoric Acid.
- analytical solvent: Acetonitrile
- minimum time: 15 Minutes
- maximum flow rate: 1.0 L/min
- current analytical method: High Performance Liquid Chromatography; HPLC/UV
- method reference: OSHA Salt Lake Technical Center In-House File
- method classification: Not Validated
- note: Samples must be kept at reduced temperature and shipped overnight to lab cold.