Registration Dossier
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 200-753-7 | CAS number: 71-43-2
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data

Repeated dose toxicity: inhalation
Administrative data
- Endpoint:
- chronic toxicity: inhalation
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: GLP-status unknown, non-guideline, animal experimental study, published in peer-reviewed literature, notable limitations in design and reporting but contributing to a weight of evidence
Data source
Reference
- Reference Type:
- publication
- Title:
- Benzene hematotoxicity and leukemogenesis
- Author:
- Cronkite EP, Drew RT, Inoue T and Bullis JE
- Year:
- 1 985
- Bibliographic source:
- Am. J. Ind. Med. 7, 447-456
Materials and methods
Test guideline
- Qualifier:
- no guideline followed
- Principles of method if other than guideline:
- Eight to twelve-week old male and female C57B1/6 BNL mice were exposed to air or benzene vapour in air. At various times during and after the exposure period, five to ten mice were removed from both the treated and control groups and the blood, bone marrow and spleens removed and examined for evidence of haematotoxicity.
- GLP compliance:
- not specified
- Limit test:
- no
Test material
- Reference substance name:
- Benzene
- EC Number:
- 200-753-7
- EC Name:
- Benzene
- Cas Number:
- 71-43-2
- Molecular formula:
- C6H6
- IUPAC Name:
- benzene
- Test material form:
- other: no data
- Details on test material:
- Common name: Benzene
No other data provided
Constituent 1
Test animals
- Species:
- mouse
- Strain:
- C57BL
- Sex:
- male/female
Administration / exposure
- Route of administration:
- inhalation: vapour
- Type of inhalation exposure:
- whole body
- Vehicle:
- other: air
- Details on inhalation exposure:
- GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: details on construction and design reported elsewhere
- Generation of vapour: No details reported - Analytical verification of doses or concentrations:
- not specified
- Duration of treatment / exposure:
- 2-16 weeks
- Frequency of treatment:
- 6 h/day, 5 days/week or 3 consecutive days/week
Doses / concentrationsopen allclose all
- Remarks:
- Doses / Concentrations:
0, 10, 25, 100, 300, 400 ppm (0, 32, 80, 320, 960, 1280 mg/m3)
Basis:
other: target concentration - (6h/d, 5d/wk for 2-16 wks)
- Remarks:
- Doses / Concentrations:
0, 300 ppm (960 mg/m3)
Basis:
other: target concentration - (6h/day, 3 d/week for 8 weeks)
- No. of animals per sex per dose:
- No specific detail. At 300 ppm for 16 weeks 88 control and 89 exposed females
- Control animals:
- yes, concurrent no treatment
- Details on study design:
- Post-exposure period: 16 weeks
Results and discussion
Effect levels
open allclose all
- Dose descriptor:
- NOAEC
- Effect level:
- 10 ppm
- Sex:
- male/female
- Basis for effect level:
- other: lymphocytopenia after 10 expousres at 25 ppm
- Dose descriptor:
- NOAEC
- Effect level:
- 32 mg/m³ air (nominal)
- Sex:
- male/female
- Basis for effect level:
- other: lymphocytopenia after 10 expousres at 80 mg/m3
Target system / organ toxicity
- Critical effects observed:
- not specified
Any other information on results incl. tables
Benzene (100 ppm or higher for 6 h/day, 5 days/week for 2 weeks) produced a reduction in bone marrow cellularity and the number of pluripotent stem cells in the bone marrow. There was also as increase in the fraction of stem cells in DNA synthesis. At 25 ppm lymphocyte concentration in peripheral blood was decreased. Exposure to 300 ppm 6 h/day, 5 days/ week for 2, 4, 8, and 16 weeks produced a diminution in the stem cell levels in bone marrow. Stem cells returned to control levels 2 weeks after the end of benzene exposure for 2 and 4 weeks, 16 weeks after exposure for 8 weeks, and to 92% of controls 25 weeks after 16 weeks of exposure. Blood lymphocytes showed a more rapid return to the control level.
Applicant's summary and conclusion
- Conclusions:
- Repeated inhalation exposure to benzene at 6h/day, 5 days/week produces haematotoxicity in mice. The NOAEC was 10 ppm (32 mg/m3).
- Executive summary:
Haematotoxicity was examined in male and female C57Bl/6 BNL mice exposed to benzene vapour at concentrations of 0, 10, 25, 100, 300 or 400 ppm benzene for 2 -16 weeks. At various times during and after the exposure period, five to ten mice were removed from both the treated and control groups and the blood, bone marrow and spleens removed and examined.
At ≥100 ppm for 10 exposures benzene produced a reduction in bone marrow cellularity and the number of pluripotent stem cells in the bone marrow. The fraction of stem cells in DNA synthesis was also increased. At 25 ppm lymphocyte concentration was decreased. 16 weeks of exposure to 300 ppm benzene, 6 h/day, 5 days/week, produced a diminution in the haemopoietic stem cells with incomplete recovery 16 weeks after termination of exposure although full recovery was seen with shorter exposure durations (2, 4 or 8 weeks). There was a more rapid return of blood lymphocytes to control levels.
The NOAEC for haematotoxicity was 10 ppm (32 mg/m3).
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.

Route: .live2