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EC number: 248-655-3 | CAS number: 27776-21-2
- 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
Endpoint summary
Administrative data
Description of key information
Key value for chemical safety assessment
Skin irritation / corrosion
Link to relevant study records
- Endpoint:
- skin irritation: in vivo
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- comparable to guideline study
- Qualifier:
- equivalent or similar to guideline
- Guideline:
- OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
- Deviations:
- yes
- Remarks:
- Number of animals: 6; Exposure time: 24 h; Intact and abraded skin was exposed
- GLP compliance:
- no
- Species:
- rabbit
- Strain:
- New Zealand White
- Details on test animals or test system and environmental conditions:
- The rabbits were individually house in metal cages,
Room temperature: 19 °C
Relative humidity: 30-70 %
Air exchange: 19/h
Aritificial light: 12h in each 24 hour period - Preparation of test site:
- other: abraded and intact skin
- Vehicle:
- water
- Controls:
- not required
- Amount / concentration applied:
- 0,5 g amount of 2,2’-[azobis(1-methylethylidene)]bis[4,5-dihydro-1H-imidazole dihydrochloride, was applied under a 2.5 cm square gauze pad moist with 0,5mL distiiled water
- Duration of treatment / exposure:
- 24 h
- Observation period:
- 24 and 72 h
- Number of animals:
- 6
- Irritation parameter:
- erythema score
- Remarks:
- Intact skin
- Basis:
- mean
- Time point:
- 24/48/72 h
- Score:
- 0
- Max. score:
- 4
- Reversibility:
- fully reversible
- Irritation parameter:
- erythema score
- Remarks:
- Abraded skin
- Basis:
- mean
- Time point:
- 24/48/72 h
- Score:
- 0
- Max. score:
- 4
- Reversibility:
- fully reversible
- Irritation parameter:
- edema score
- Remarks:
- Intact skin
- Basis:
- mean
- Time point:
- 24/48/72 h
- Score:
- 0
- Max. score:
- 4
- Reversibility:
- fully reversible
- Irritation parameter:
- edema score
- Remarks:
- Abraded skin
- Basis:
- mean
- Time point:
- 24/48/72 h
- Score:
- 0
- Max. score:
- 4
- Reversibility:
- fully reversible
- Interpretation of results:
- other: Based on "Appraisal of the Safety of Chemicals in Foods, Drugs, and Cosmetics", published by the Association of Food and Drug Officials of the United States, 1959, p. 46.
- Conclusions:
- 2,2’-[azobis(1-methylethylidene)]bis[4,5-dihydro-1H-imidazole dihydrochloride is considered to be non - irritant to rabbit skin
Reference
Erythema and Eschar Formation
No erythema...................................................................................................................... 0
Very slight erythema (barely perceptible) ............................................................. ........... 1
Well defined erythema .................................................................................................... ...2
Moderate to severe erythema ...................................................................................... ...... 3
Severe erythema (beef redness) to eschar formation preventing grading of erythema..... ... 4
Maximum possible: 4
Oedema Formation No oedema ............................................................................................ 0
Very slight oedema (barely perceptible) ...................................................... ...... . 1
Slight oedema (edges of area well defined by definite raising) .............................. ............ 2
Moderate oedema (raised approximately 1 mm) 3
Severe oedema (raised more than 1 mm and extending beyond area of exposure) ......... ..... 4
Maximum possible: 4
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed (not irritating)
Eye irritation
Link to relevant study records
- Endpoint:
- eye irritation: in vitro / ex vivo
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage)
- GLP compliance:
- yes (incl. QA statement)
- Species:
- cattle
- Strain:
- not specified
- Details on test animals or tissues and environmental conditions:
- Isolated bovine cornea: The test system (target tissue) is the isolated bovine cornea. Bovine eyes are obtained as a by-product of freshly slaughtered cattle (age of the animals: minimum 12 months, maximum 60 months).
- Vehicle:
- other: De-ionized water
- Controls:
- yes, concurrent positive control
- yes, concurrent negative control
- Amount / concentration applied:
- 20% (w/v) solution in de-ionized water
- Duration of treatment / exposure:
- The corneas were incubated in a horizontal position at about 32 °C for approximately 4 hours (non-surfactant solids).
- Number of animals or in vitro replicates:
- Each treatment group (test substance, NC and PC) consisted of 3 corneas
- Irritation parameter:
- in vitro irritation score
- Value:
- 2.6
- Vehicle controls validity:
- valid
- Negative controls validity:
- valid
- Positive controls validity:
- valid
- Interpretation of results:
- GHS criteria not met
- Remarks:
- The IVIS score of the test substance of 2.6 would classify it as a substance that does not cause eye irritation or serious eye damage
- Conclusions:
- Applying the criteria of the OECD 437 for the assessment of the BCOP test results, the IVIS score of the test substance of 2.6 would classify it as a substance that does not cause eye irritation or serious eye damage. However, the Guideline also states, that due to limited accuracy of the BCOP test to correctly identify substances that do not require classification for eye irritation or serious eye damage, this test method should not be the first choice to initiate a bottom-up approach. Based on this statement test substances leading to IVIS <3 are generally examined in the EpiOcular test as well.
- Endpoint:
- eye irritation, other
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 405 (Acute Eye Irritation / Corrosion)
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 492 (Reconstructed Human Cornea-like Epithelium (RhCE) Test Method for Identifying Chemicals Not Requiring Classification and Labelling for Eye Irritation or Serious Eye Damage)
- Version / remarks:
- adopted 28. July 2015
- GLP compliance:
- yes (incl. QA statement)
- Species:
- human
- Details on test animals or tissues and environmental conditions:
- The EpiOcularTM model (OCL-200) is a three-dimensional non-keratinized tissue construct composed of normal human derived epidermal keratinocytes used to model the human corneal epithelium. The EpiOcularTM tissues (surface 0.6 cm²) arecultured on especially prepared cell culture inserts and are
commercially available as kits (EpiOcular™ 200), containing 24 tissues on shipping agarose. - Vehicle:
- other: The test substance is applied undiluted, therefore no preparation of the test substance in a vehicle was performed
- Controls:
- yes, concurrent positive control
- yes, concurrent negative control
- Amount / concentration applied:
- A volume of 50 μL of the test material was applied covering the whole tissue surface.
- Duration of treatment / exposure:
- exposure time: 6 hours
- Duration of post- treatment incubation (in vitro):
- Postincubation period: 18 h
- Number of animals or in vitro replicates:
- 3
- Irritation parameter:
- other: Optical density (wavelength 570 nm)
- Value:
- 4
- Negative controls validity:
- valid
- Remarks:
- 100
- Positive controls validity:
- valid
- Remarks:
- 21
- Interpretation of results:
- Category 2 (irritating to eyes) based on GHS criteria
- Conclusions:
- In the current case, the EpiOcular test was positive and the test substance was assessed to be irritating.
- Executive summary:
Applying the criteria of the OECD 437 for the assessment of the BCOP test results, the IVIS score of the test substance of 2.6 would classify it as a substance that does not cause eye irritation or serious eye damage. However, the Guideline also states, that due to limited accuracy of the BCOP test to correctly identify substances that do not require classification for eye irritation or serious eye damage, this test method should not be the first choice to initiate a bottom-up approach. Based on this statement and the experience of the test facility, test substances leading to IVIS < 3 are generally examined in the EpiOcular test as well. In the current case, the EpiOcular test was positive and the test substance was assessed to be irritating.
Based on the results for BCOP and EpiOcular Test and applying the evaluation criteria described in section 3.10, Azo Initiator VA044 shows an eye irritation potential in the in vitro eye irritation test strategy under the test conditions chosen.
Referenceopen allclose all
Endpoint conclusion
- Endpoint conclusion:
- adverse effect observed (irritating)
Respiratory irritation
Endpoint conclusion
- Endpoint conclusion:
- no study available
Additional information
Justification for classification or non-classification
Skin irritation/corrosion:
2,2’-[azobis(1-methylethylidene)]bis[4,5-dihydro-1H-imidazole dihydrochloride is considered to be non - irritant to rabbit skin
Eye irritation:
In the current case, the EpiOcular test was positive and the test substance was assessed to be eye irritating. Based on the findings the substance is considered to fulfil the criteria for classification of eye irritant category 2.
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