Diphenylacetic acid

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

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 publication.

Data source

Reference

Reference Type:

publication

Title:

Pigmented contact dermatitis from azo dyes.

Author:

Kgzuka T, Tashiro M, Sano S, Fujimoto K, Nakamura Y, Hashimoto S, Nakaminami G.

Year:

1980

Bibliographic source:

Contact Dermatitis 1980: 6: 330-336.

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: as below

Principles of method if other than guideline:

The patch test were performed with Finn Chambers on Scanpor. The application was performed for 2 days. Readings were made according to the ICDRG classification 24 hours after the patches were removed.

GLP compliance:

not specified

Type of study:

patch test

Justification for non-LLNA method:

Not specified

Test material

Test material information

Constituent 1

Reference substance name:

3-hydroxy-2-naphthoic acid

EC Number:

202-180-8

EC Name:

3-hydroxy-2-naphthoic acid

Cas Number:

92-70-6

Molecular formula:

C11H8O3

IUPAC Name:

3-hydroxy-2-naphthoic acid /

Test material form:

solid

Details on test material:

- Name of test material (as cited in study report): 2-Hydroxy-3-naphthoic acid (3-hydroxy-2-naphthoic acid)
- Molecular formula (if other than submission substance): C11H8O3
- Molecular weight (if other than submission substance): 188.179 g/mol
- Substance type: Organic
- Physical state: solid
- Purity: no data
- Impurities (identity and concentrations): no data

Specific details on test material used for the study:

- Name of test material (as cited in study report): 2-Hydroxy-3-naphthoic acid (3-hydroxy-2-naphthoic acid)
- Molecular formula (if other than submission substance): C11H8O3
- Molecular weight (if other than submission substance): 188.179 g/mol
- Substance type: Organic
- Physical state: solid
- Purity: no data
- Impurities (identity and concentrations): no data

In vivo test system

Test animals

Species:

other: Human

Strain:

other: Not applicable

Sex:

not specified

Details on test animals and environmental conditions:

No data

Study design: in vivo (non-LLNA)

Induction

Route:

epicutaneous, semiocclusive

Vehicle:

petrolatum

Concentration / amount:

1%

Day(s)/duration:

48 h

Adequacy of induction:

not specified

Challenge

No.:

#1

Route:

epicutaneous, semiocclusive

Vehicle:

petrolatum

Concentration / amount:

1%

Day(s)/duration:

24 h

Adequacy of challenge:

not specified

No. of animals per dose:

8 human volunteers

Details on study design:

Details on study design
RANGE FINDING TESTS:

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: no data
- Exposure period: 48 h
- Test groups: yes
- Control group: yes (28 females)
- Site: on the back
- Frequency of applications: no data
- Duration: 48 h
- Concentrations: 1%

B. CHALLENGE EXPOSURE
- No. of exposures: no data
- Day(s) of challenge: 1 day
- Exposure period: 1 day
- Test groups: yes
- Control group: yes (28 females)
- Site: on the back
- Concentrations: 1%
- Evaluation (hr after challenge): 24 h

OTHER:

Challenge controls:

Twenty-eight healthy female volunteers, aged 20 and 21, were also tested with these samples as controls. None gave a positive reaction to them.

Positive control substance(s):

not specified

Results and discussion

Positive control results:

No data available

In vivo (non-LLNA)

Results

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

1%

No. with + reactions:

0

Total no. in group:

8

Clinical observations:

No positive reactions were observed

Remarks on result:

no indication of skin sensitisation

Applicant's summary and conclusion

Interpretation of results:

other: Not sensitizing

Conclusions:

During the test none of the patients had a positive reaction, when 3-hydroxy-2-naphthoic acid applied onto the skin of human volunteers. Hence the 3-hydroxy-2-naphthoic acid is not sensitizing to human.

Executive summary:

The Patch test was performed on the back of eight human volunteers for 2 days. Readings were made according to the ICDRG classification 24 h after the patches were removed. Patch test concentration is 1 % in petrolatum. All eight showed negative reaction to 3-hydroxy-2-naphthoic acid. Twenty eight healthy female volunteers, aged 20 and 21, were also tested as controls. None gave a positive reaction. On the basis of negative reaction of skin sensitization obtained it was concluded that the test material 3-hydroxy-2-naphthoic acid is not sensitizing to human.