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Benzene

General Description

  • Synonyms: Benzine; Benzol; Cyclohexatriene
  • OSHA IMIS Code Number: 0320
  • Chemical Abstracts Service (CAS) Registry Number: 71-43-2
  • NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: CY1400000
  • Department of Transportation Regulation Number (49 CFR 172.101) and Emergency Response Guidebook: 1114 130
  • NIOSH Pocket Guide to Chemical Hazards, Benzene: Physical description, chemical properties, potentially hazardous incompatibilities, and more
  • U.S. Environmental Protection Agency (EPA) Hazard Summary, Benzene: Uses, sources and potential exposure, acute and chronic health hazard information, and more

Exposure Limits and Health Effects

    Exposure Limit Limit Values HE Codes Health Factors and Target Organs
    OSHA Permissible Exposure Limit (PEL) - General Industry
    See 29 CFR 1910.1028
    1 ppm
    TWA

    5 ppm
    STEL
    HE1 Leukemia
    HE7 Central nervous system excitation followed by central nervous system depression
    HE8 Loss of consciousness, respiratory paralysis, death (very high concentrations)
    HE12 Nonmalignant blood disorders (bleeding, anemia, aplastic anemia, thrombocytopenia, leukopenia)
    HE14 Eye, nose, and respiratory irritation
    OSHA PEL - Sectors Excluded from General Industry
    See 1910.1000 Table Z-2
    (See also Z37.40-1969)

    Note: These values apply to the industry segments exempt from the 1 ppm 8-hour TWA and 5 ppm STEL of the benzene standard at 1910.1028.
    10 ppm
    TWA

    25 ppm
    Ceiling

    50 ppm Maximum peak above ceiling
    (10 minutes)
    HE12 Blood disorders (anemia, leukopenia, aplastic anemia)
    HE14 Eye, nose, and respiratory irritation
    OSHA PEL - Construction Industry
    See 29 CFR 1926.1128
    1 ppm
    TWA

    5 ppm
    STEL
    HE1 Leukemia
    HE7 Central nervous system excitation followed by central nervous system depression
    HE8 Loss of consciousness, respiratory paralysis, death (very high concentrations)
    HE12 Nonmalignant blood disorders (bleeding, anemia, aplastic anemia, thrombocytopenia, leukopenia)
    HE14 Eye, nose, and respiratory irritation
    OSHA PEL - Shipyard Employment
    See 29 CFR 1915.1028
    1 ppm
    TWA

    5 ppm
    STEL
    HE1 Leukemia
    HE7 Central nervous system excitation followed by central nervous system depression
    HE8 Loss of consciousness, respiratory paralysis, death (very high concentrations)
    HE12 Nonmalignant blood disorders (bleeding, anemia, aplastic anemia, thrombocytopenia, leukopenia)
    HE14 Eye, nose, and respiratory irritation
    National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL) 0.1 ppm
    TWA

    1 ppm
    STEL

    Ca
    HE1 Leukemia
    HE4 Gastrointestinal irritation and anorexia; cardiac sensitization
    HE7 Central nervous system depression; convulsions and paralysis; polyneuritis
    HE11 Pulmonary edema, pneumonia
    HE12 Bone marrow damage, aplastic anemia
    HE14 Eye, mucous membrane, and skin irritation; dermatitis
    American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) (2001) 0.5 ppm
    (1.6 mg/m3)
    TWA

    2.5 ppm
    (8 mg/m3)
    STEL

    A1; Skin; BEI
    HE1 Leukemia, including acute myelogenous leukemia
    CAL/OSHA PELs
    (See also Section 5218)
    1 ppm
    TWA

    5 ppm
    STEL

    Skin
       
  • National Toxicology Program (NTP) carcinogenic classification: Known to be a human carcinogen (PDF)
  • International Agency for Research on Cancer (IARC) carcinogenic classification: Group 1 (carcinogenic to humans)
  • EPA carcinogenic classification: Known/likely human carcinogen
  • EPA Inhalation Reference Concentration (RfC): 3x10-2 mg/m3
  • Agency for Toxic Substances and Disease Registry (ATSDR) Inhalation Minimal Risk Levels (MRLs): 0.009 ppm (acute); 0.006 ppm (intermediate); 0.003 ppm (chronic)
  • NIOSH Immediately Dangerous To Life or Health Concentration (IDLH): 500 ppm
  • Notes on Other Potential Health Effects and Hazards
    1. Benzene is a flammable liquid whose vapors can form explosive mixtures (NIOSH/IPCS 2003).
    2. While percutaneous absorption of liquid benzene through intact human skin can be limited, the absorbed dose via direct dermal contact, combined with that received from body surface exposure to benzene in workplace air, is such that a substantial fraction of the total exposure is due to skin absorption (ACGIH 2001).
    3. Phenol levels in urine have been used as an index of benzene exposure, where concentrations of 200 mg/L urine indicate an approximate exposure of 25 ppm benzene in air (OSHA 1980).
    4. Ventricular fibrillation has been suggested as the cause of death following benzene vapor exposures (ATSDR 2007).
    5. Myalgia has been reported as a symptom of exposure to benzene vapors (ATSDR 2007).
    6. Benzene may also affect the renal system, as kidney congestion has been found following fatal inhalational exposure (ATSDR 2007).
    7. An association may exist between occupational exposure to benzene and non-Hodgkin’s lymphoma and multiple myeloma (ATSDR 2007).
    8. Benzene appears to affect the immune system, where workers have been shown to have decreased levels of leukocytes and circulating antibodies (ATSDR 2007).
    9. Exposure to benzene is associated with aneuploidies in blood cells and sperm (Ji et al. 2012).
    10. Exposure to benzene may play a role in infertility, as workers have increased incidence of chromosomally defective sperm, which could result in spontaneous abortions, mental retardation, and inherited defects in their children (Marchetti et al. 2012).
    11. An association may exist between mothers exposed to benzene and children with spina bifida (Lupo et al. 2011).
    12. Exposure to benzene may increase the risk of acoustic neuroma, a benign intracranial tumor (Prochazka et al. 2010).
    13. In one study, no association was found between occupational benzene exposure and breast cancer (Peplonska et al. 2010). However, another study "moderately supports" an association between benzene and breast cancer (Costantini et al. 2009).
  • Date Last Revised: 9/6/2012
  •  
  • Literature Basis:
    • ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Benzene. 2001.
    • ANSI (formerly United States of America Standards Institute): USA Standard Acceptable Concentrations of Benzene. September 1969.
    • ATSDR: Toxicological Profile for Benzene. 2007.
    • Costatini, A.S., Gorini, G., Consonni, D., Miligi, L., Giovannetti, L., Quinn, M.: Exposure to benzene and risk of breast cancer among shoe factory workers in Italy. Tumori. 95(1):8-12, January-February 2009.
    • Ji, Z., Weldon, R.H., Marchetti, F., Chen, H., Li, G., Xing, C., Kurtovich, E., Young, S., Schmid, T.E., Waidyanatha, S., Rappaport, S., Zhang, L., Eskenazi, B.: Comparison of aneuploidies of chromocomes 21, X, and Y in the blood lymphocytes and sperm of workers exposed to benzene. Environ Mol Mutagen. 53(3):218-26, April 2012.
    • Lupo, P.J., Symanski, E., Waller, D.K., Chan, W., Langlois, P.H., Canfield, M.A., Mitchell, L.E.: Maternal exposure to ambient levels of benzene and neural tube defects among offspring: Texas, 1999-2004. Environ Health Perspect. 119(3):397-402, March 2011.
    • Marchetti, F., Eskenazi, B., Weldon. R.H., Li, G., Zhang, L., Rappaport, S.M., Schmid, T.E., Xing, C., Kurtovich, E., Wyrobek, A.J.: Occupational exposure to benzene and chromosomal structural aberrations in the sperm of Chinese men. Environ Health Perspect. 120(2):229-34, February 2012.
    • NIOSH: Occupational Health Guideline - Benzene. 1988.
    • NIOSH/IPCS: International Chemical Safety Card - Benzene. 2003.
    • OSHA: Occupational Safety and Health Standards, Substance safety data sheet - Benzene. 1910.1028 App A.
    • OSHA: Occupational Safety and Health Standards, Medical surveillance guidelines - Benzene. 1910.1028 App C.
    • Peplonska, B., Stewart, P., Szeszenia-Dabrowska, N., Lissowska, J., Brinton, L.A., Gromiec, J.P., Brzeznicki, S., Yang, X.R., Sherman, M., Garcia-Closas, M., Blair, A.: Occupational exposure to organic solvents and breast cancer in women. Occup Environ Med. 67(11):722-9, November 2010.
    • Prochazka, M., Feychting, M., Ahlbom, A., Edwards, C.G., Nise, G., Plato, N., Schwartzbaum, J.A., Forssen, U.M.: Occupational exposures and risk of acoustic neuroma. Occup Environ Med. 67(11):766-71, November 2010.

Monitoring Methods used by OSHA

Primary Laboratory Sampling/Analytical Method :
  • Charcoal Tube (100/50 mg sections)
  • analytical solvent: Carbon Disulfide
  • alternate solvent: (99:1) Carbon Disulfide:Dimethylformamide
  • maximum volume: 12 Liters
  • maximum flow rate: 0.05 L/min TWA
  • maximum volume: 0.75 Liters
  • maximum flow rate: 0.05 L/min STEL
  • minimum time: 15 Minutes
  • maximum flow rate: 0.05 L/min Ceiling
  • minimum time: 10 Minutes   
  • maximum flow rate: 0.05 L/min (Peak)
  • current analytical method: Gas Chromatography;GC/FID
  • method reference: OSHA Analytical Method (OSHA 1005)
  • method classification: Fully Validated
  • Diffusive Sampler (3M 3520 Orgainc Vapor Monitor)
  • analytical solvent: Carbon Disulfide
  • alternate solvent: (99:1) Carbon Disulfide:Dimethylformamide
  • sampling time: 10 to 240 Min
  • current analytical method: Gas Chromatography;GC/FID
  • method reference: OSHA Analytical Method (OSHA 1005)
  • method classification: Fully Validated
  • note: Persons using diffusive samplers to monitor workplace air must ensure that the sampling devices are properly closed before transporting such devices to the laboratory for analysis. The device will continue to sample until properly closed. Diffusive sampler accessories used for analysis of samplers must be included with transported samples. Persons using such devices must provide sampling-site station barometric pressure and temperature to the analytical laboratory to improve accuracy of sampling results.
  • Diffusive Sampler (SKC 575-002 Passive Sampler)
  • analytical solvent: Carbon Disulfide
  • alternate solvent: (99:1) Carbon Disulfide:Dimethylformamide
  • sampling time: 10 to 240 Min
  • current analytical method: Gas Chromatography;GC/FID
  • method reference: OSHA Analytical Method (OSHA 1005)
  • method classification: Fully Validated
  • note: Persons using diffusive samplers to monitor workplace air must ensure that the sampling devices are properly closed before transporting such devices to the laboratory for analysis. The device will continue to sample until properly closed. Diffusive sampler accessories used for analysis of samplers must be included with transported samples. Persons using such devices must provide sampling-site station barometric pressure and temperature to the analytical laboratory to improve accuracy of sampling results.
On-Site Sampling Techniques/Methods:
  • Detector Tube
  • manufacturer: Gastec
  • model/type: 121
  • sampling information: 1 to 4 strokes
  • upper measurement limit: 120 ppm
  • detection limit: 0.5 ppm
  • overall uncertainty: 16.4% for 5 to 20 ppm, 8.2% for 20 to 60 ppm
  • method reference: on-site air secondary (SEI Certified)
  • Detector Tube
  • manufacturer: Matheson-Kitagawa
  • model/type: 8014-118SC
  • sampling information: follow manufacturer's instructions
  • upper measurement limit: 100 ppm
  • detection limit: approximately 0.2 ppm
  • overall uncertainty: unknown
  • method reference: on-site air secondary (SEI Certified)
  • Detector Tube
  • manufacturer: Dräger
  • model/type: Benzene 5/b, order no. 67 28071
  • sampling information: 20 strokes
  • upper measurement limit: 50 ppm
  • detection limit: approximately 1 ppm
  • overall uncertainty: 25%
  • method reference: on-site air secondary (manufacturer)
Wipe Sampling Method:
  • charcoal pad from 3M 3500 or 3520 Organic Vapor Monitor
  • analytical solvent: none
  • note: Ship sample in a sealed 20 mL glass scintillation vial.
Bulk Method:
  • current analytical method: High performance liquid chromatography; HPLC/UV
  • method reference: OSHA Analytical Method (OSHA 12)
  • method classification: Fully Validated
  • note: Do not ship bulk samples with air samples.

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