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Chemical Sampling Information (CSI)
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General Description

Synonyms: 2-Furaldehyde; Furfuraldehyde; Fural; 2-Furancarboxaldehyde

OSHA IMIS Code Number: 1325

Chemical Abstracts Service (CAS) Registry Number: 98-01-1

NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: LT7000000

Department of Transportation Regulation Number (49 CFR 172.101) and Guide: 1199 132P

NIOSH Pocket Guide to Chemical Hazards, Furfural: chemical description, physical properties, potentially hazardous incompatibilities, and more

Exposure Limits

OSHA Permissible Exposure Limit (PEL):

General Industry: 29 CFR 1910.1000 Z-1 Table -- 5 ppm, 20 mg/m3 TWA; Skin

Construction Industry: 29 CFR 1926.55 Appendix A -- 5 ppm, 20 mg/m3 TWA; Skin

Maritime: 29 CFR 1915.1000 Table Z-Shipyards -- 5 ppm, 20 mg/m3 TWA; Skin

American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV): 2 ppm, 7.9 mg/m3 TWA; Skin; Appendix A3 - Confirmed Animal Carcinogen with Unknown Relevance to Humans; BEI

National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): Appendix D - Substances With No Established RELs

Health Factors

Carcinogenic Classification:

International Agency for Research on Cancer (IARC): Group 3, not classifiable as to its carcinogenicity to humans [103 KB PDF, 39 pages]

NIOSH Immediately Dangerous To Life or Health Concentration (IDLH): 100 ppm

Potential Symptoms: Irritation of eyes, skin, upper respiratory irritation; headache; sore throat, cough, shortness of breath; INGES. ACUTE: Abdominal pain; diarrhea, headache, sore throat, vomiting.

Health Effects: Irritation- Eyes---Marked (HE14); Irritation-Nose, Throat, Skin---Mild (HE16)

Affected Organs: Eyes, skin, respiratory system


  1. Approximately 78% of inhaled furfural is absorbed and is excreted in the urine mostly as the glycine conjugate of furoic acid (furoylglycine), with a biological half-life of 2-2.5 hours. Significant absorption of furfural can occur through the skin.
  2. The LC50 of furfural in rats (1-hour exposure) was reported to be 189 ppm.
  3. Subacute inhalation studies in rats reported histopathological nasal changes with furfural concentrations as low as OSHAs PEL (20 mg/m3 = 5 ppm). In mice, the concentration that decreased respiration by 50% (RD50) was in the range of 234-287 ppm.
  4. EPAs reference dose (RfD, daily oral exposure likely to be without an appreciable risk of deleterious effects during a lifetime) for furfural is 0.003 mg/kg/day. This RfD is 1/100 the amount of furfural and its precursors (furfuryl alcohol and furfuryl esters) estimated to be consumed daily in foods and beverages. Others have proposed an oral RfD of 0.03 mg/kg/day.
  5. The Appendix in NIOSHs Alert on food flavorings lists furfural as a flavoring substance. The FDA has not formally evaluated the safety of furfural use as a food-flavoring ingredient. However, as permitted by law, the Flavor and Extract Manufacturers Association has independently determined that furfural is generally recognized as safe as a flavor ingredient. To date, the FDA has not questioned that determination.
  6. EPA received an application for the use of furfural as a fungicide for greenhouse soil treatment, turf and ornamental (non-food) plants.
  7. NIOSH reported an abundant (but not quantified) concentration of furfural among several volatile organic compounds (VOC) identified in commercial bulk liquid butter flavoring heated to 50C. VOC from butter flavorings have been causally implicated in occupational lung disease, including bronchiolitis obliterans (see also Diacetyl).
  8. Relatively high concentrations of furfural have been reported for surgical smoke (vapors from electrocautery) when sampled at 2 cm from the point of origin.

Literature Basis:

  • NIOSH Pocket Guide to Chemical Hazards: Furfural.
  • International Chemical Safety Cards (WHO/IPCS/ILO): Furfural.
  • U.S. EPA Integrated Risk Information System: Furfural (CASRN 98-01-1).
  • U.S. EPA Multi-Year Workplan for Conventional Pesticide Registration.
  • Adams, T.B., et al.: The FEMA GRAS assessment of furfural used as a flavour ingredient. Flavor and Extract Manufacturers Association. Food Chem. Toxicol. 35(8): 739-751, 1997.
  • Arts, J.H.E., de Heer, C. and Woutersen, R.A.: Local effects in the respiratory tract: relevance of subjectively measured irritation for setting occupational exposure limits. Int. Arch. Occup. Environ. Health 79(4): 283-298, 2006.
  • Arts, J.H., Muijser, H., Appel, M.J., Frieke Kuper, C. Bessems, J.G. and Woutersen, R.A.: Subacute (28-day) toxicity of furfural in Fischer 344 rats: a comparison of the oral and inhalation route. Food. Chem. Toxicol. 42(9): 1389-1399, 2004.
  • Boylstein, R., Piacitelli, C., Grote, A., Kanwal, R., Kullman, G. and Kreiss, K.: Diacetyl emissions and airborne dust from butter flavorings used in microwave popcorn production. J. Occup. Environ. Hyg. 3(10): 530-535, 2006.
  • Ewing, A., Phelka, A., Ball, G. and McLellan, C.: Human health risk assessment of furfural to determine drinking water action levels (Abstract). Toxicologist 78(Suppl. 1): 151, 2004.
  • Flek, J. and edivec, V.: The absorption, metabolism and excretion of furfural in man. Int. Arch. Occup. Environ. Health 41(3): 159-168, 1978.
  • Hollmann, R., Hort, C.E., Kammer, E., Naegele, M., Sigrist, M.W. and Meuli-Simmen, C.: Smoke in the operating theater: an unregarded source of danger. Plast. Reconstr. Surg. 114(2): 458-463, 2004.
  • Mishra, A., et al.: Pathological and biochemical alterations induced by inhalation of furfural vapor in rat lung. Bull. Environ. Contam. Toxicol. 47(): 668-674, 1991.
  • NIOSH Alert: Preventing Lung Disease in Workers Who Use or Make Flavorings. HHS (NIOSH) Publication Number 2004-110.
  • No authors listed: 2-Furaldehyde. Concise international chemical assessment document 21. Geneva: World Health Organization, 2000, 43 pp.
  • No authors listed: Furfural. [103 KB PDF, 39 pages]. IARC Monogr. Eval. Carcinog. Risks Hum. 63: 409-429, 1995.
  • Pohanish, R.P. (editor): Furfural. In, Sittigs Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 1. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1196-1198.
  • Rodriguez-Kabana, R., Kloepper, J.W., Weaver, C.F. and Robertson, D.G.: Control of plant parasitic nematodes with furfural: a naturally occurring fumigant. Nematropica 23(1): 63-73, 1993.

Date Last Revised: 10/26/2006

Monitoring Methods used by OSHA

Primary Laboratory Sampling/Analytical Method (SLC1):

  • sampling media: Petroleum Base Charcoal Tube (100/50 mg sections, 20/40 mesh)
    analytical solvent: (99:1) Carbon Disulfide:Dimethylformamide
    maximum volume: 180 Liters
    maximum flow rate: 1.0 L/min
    current analytical method: Gas Chromatography; GC/FID
    method reference: OSHA Analytical Method (OSHA 72)
    method classification: Fully Validated

Wipe Sampling Method:

  • sampling media: charcoal pad
    note: seal in glass vial for shipment
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