Benzoic acid

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation / corrosion, other

Remarks:

Study predates requirements to perform in vitro screening ahead of in vivo studies.

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Limited study details published. Not GLP. Despite its reliability score of K2, this study is considered as Key study (in favour over other K1 studies) on the grounds that the Guinea-pig response is considered as more consistent with human responses.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Groups of ten adult female guinea pigs, rats, and mice were used for each challenge. The thicknesses of the earlobes were measured.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Benzoic acid

EC Number:

200-618-2

EC Name:

Benzoic acid

Cas Number:

65-85-0

Molecular formula:

C7H6O2

IUPAC Name:

benzoic acid

Details on test material:

Batch No.: not specifiedPurity: not specified

Test animals

Species:

other: guinea pig, rat and mouse

Strain:

other: Hartley, Sprague-Dawley and ICR

Details on test animals or test system and environmental conditions:

TEST ANIMALS- Source: Guinea pigs from Charles River Breeding Laboratories, Wilmington, MA; rats from Bantin & Kingman, Inc., Fremont, CA; mice from Simonsen Laboratories, Inc., Gilroy, CA.- Age at study initiation: adult- Weight at study initiation: Guinea pigs weight 350-500 gm, rats weight 180-210 gm.No additional data

Test system

Type of coverage:

not specified

Preparation of test site:

not specified

Vehicle:

other: ethyl alcohol

Controls:

not required

Amount / concentration applied:

TEST MATERIAL- Amount(s) applied (volume or weight with unit): guinea pig: 50 μL; rat: 20 μL; mouse: 5 μL.- Concentration (if solution): 20%No additional data

Duration of treatment / exposure:

3 hours

Observation period:

3 hours

Number of animals:

10 females

Details on study design:

The thicknesses of the earlobes were measured three times before and every 10 minutes during the first hour, every 15 minutes during the second hour, and every 30 minutes during the third hour after application of the test substances, using a micrometer with round touching plates 6 mm in diameter. The micrometer plates were placed on the mid part of the earlobe, 1 mm from the outer rim in rat and mouse and 7 mm, in guinea pig. The means of the three measurements were used. Statistical significance was determined by Student's t test.

Results and discussion

In vivo

Results

Remarks on result:

other: In the guinea pig the test substance produced erythema and swelling of the earlobe. The test substance did not produce reactions in the mouse and rat ear.

Irritant / corrosive response data:

In the guinea pig the test substance produced erythema and swelling of the earlobe. Maximal swelling was observed at 20 to 50 minutes after application and was then seen to decrease progressively during the observation period of 3 hours. The test substance did not produce reactions in the mouse and rat ear.

Other effects:

No information provided

Applicant's summary and conclusion

Interpretation of results:

irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

In the guinea pig the test substance produced erythema and swelling of the earlobe. The test substance did not produce reactions in the mouse and rat ear. This indicates that Guinea-pig are more sensitive than either rat or mouse to irritant effects from the substance.