Registration Dossier

Toxicological information

Skin irritation / corrosion

Currently viewing:

Administrative data

Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data
Justification for type of information:
Data is from peer reviewed journals

Data source

Reference
Reference Type:
publication
Title:
Final report of the safety assessment of niacinamide and niacin.
Author:
Cosmetic Ingredients Review (CIR)
Year:
2005
Bibliographic source:
International Journal of Toxicology 24 (Suppl 5): 1-31 2005

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: as mentioned below
Principles of method if other than guideline:
Preliminary irritation tests of Niacinamide were performed in guinea pigs to determine the concentration for suitable the sensitization study.
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Details on test material:
- Name of test material (as cited in study report): Niacinamide
- Molecular formula: C6H6N2O
- Molecular weight: 122.1264 g/mol
- Substance type: Organic
- Physical state:Solid (powder)
-Smiles: c1cc(cnc1)C(=O)N
- InChI: 1S/C6H6N2O/c7-6(9)5-2-1-3-8-4-5/h1-4H,(H2,7,9)
Specific details on test material used for the study:
- Name of test material (as cited in study report): Niacinamide
- Molecular formula: C6H6N2O
- Molecular weight: 122.1264 g/mol
- Substance type: Organic
- Physical state:Solid (powder)
-Smiles: c1cc(cnc1)C(=O)N
- InChI: 1S/C6H6N2O/c7-6(9)5-2-1-3-8-4-5/h1-4H,(H2,7,9)

Test animals

Species:
guinea pig
Strain:
not specified
Details on test animals and environmental conditions:
No data available

Test system

Type of coverage:
open
Preparation of test site:
clipped
Vehicle:
physiological saline
Controls:
not specified
Amount / concentration applied:
Intradermal application: 0.1ml
Dermal application: Amount- 0.1ml
concentration applied -5% ICC and 20%ACC
Duration of treatment / exposure:
24 hours
Observation period:
24 hours
Number of animals:
Intradermal application: 8 (4/sex)
Dermal application: 4
Details on study design:
TEST SITE
- Area of exposure: small circular areas

Results and discussion

In vivo

Resultsopen allclose all
Irritation parameter:
other: Intradermal application: erythema and edema
Basis:
mean
Time point:
24 h
Reversibility:
not specified
Remarks on result:
no indication of irritation
Irritation parameter:
other: Dermal application: erythema
Basis:
mean
Time point:
24 h
Reversibility:
not specified
Remarks on result:
no indication of irritation
Irritant / corrosive response data:
No signs of irritation were observed.

Applicant's summary and conclusion

Interpretation of results:
other: not irritating
Conclusions:
Niacinamide (CAS No: -98-92-0) was considered to be not-irritating on guinea pigs in the preliminary irritation tests performed for the sensitization study.
Executive summary:

Preliminary irritation test was performed for Niacinamide(CAS No: -98-92-0) in guinea pigs to determine the concentration suitable for the sensitization study [injection challenge concentration (ICC) and application challenge concentration(ACC)].

In the preliminary test, the guinea pigs were treated intradermally and dermally.8 previously untreated guinea pigs were (4/SEX) were injected intradermally in the clipped and shaved flanks with 0.1ml aliquots of a range of concentration of test substance in physiological saline. 24 hours later, the skin was examined for erythema and edema.The concentration giving slight but perceptible irritation with no oedema was selected as the injection challenge concentration (ICC).

Aliquots of 0.1ml using a range of concentration of the test substance in distilled water were applied in small circular areas to the shaved flanks of 4 previously untreated guinea pigs.24 hours later, the skin was examined for erythema and the highest concentration which caused no irritation was selected as the application challenge concentration (ACC).

As a result of preliminary studies, the concentration of Niacinamide at which no irritation was observed were 5% for the ICC and 20% for ACC.

Since the test chemical did not induce any cutaneous effects at these concentrations, Niacinamide(CAS No: -98-92-0) was considered to be not irritating to the skin of guinea pigs.