Butyric acid

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11.10.1983 - 25.10.1983

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1983

Report date:

1983

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

1981

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Butyric acid

EC Number:

203-532-3

EC Name:

Butyric acid

Cas Number:

107-92-6

Molecular formula:

C4H8O2

IUPAC Name:

butyric acid

Details on test material:

- Name of test material (as cited in study report): n-Buttersäure
- Physical state: colorless liquid
- Analytical purity: 99,8 %
- Lot/batch No.: RM 132465
- Storage condition of test material: under darkness, 2 ° C

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Hoechst AG
- Age at study initiation: no data
- Weight at study initiation: 3.3 - 3.7 kg
- Housing: in individually cages in air-conditioned rooms
- Diet: Altromin 2123, Altromin GmbH, ad libitum
- Water: deionized chlorinated water, ad libitum
- Acclimation period: no data


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 +/- 2
- Humidity (%): 55 +/- 10
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied: 0.5 ml on a 2.5 x 2.5 cm patch

Duration of treatment / exposure:

1 hour

Observation period:

0.5-1, 24, 48, 72 hrs after removal of the patch and at day 7 and 14

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: 2.5 x 2.5 cm
- Type of wrap if used: special wound healing patches, Fa. Beiersdorf AG, Hamburg, covered and fixed with a semiocclusive bandage

REMOVAL OF TEST SUBSTANCE
- removal of test substance without washing as far as possible
- Time after start of exposure: 1 -2 hours

SCORING SYSTEM: according to Draize

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

other: all animals

Reversibility:

not reversible

Remarks on result:

other: scoring not possible due to severe skin hardening and discoloration in all animals at all time points

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 24, 48, 72 hours after patch removal

Score:

1.9

Max. score:

3

Reversibility:

not reversible

Any other information on results incl. tables

After removal of the patch, the treated skin of the test animals was discolored greenish, after one day in became brownish. One animal showed severe redness round the exposed area. In the course of observation period the treated skin surface hardened. It became dry, brittle and bulged. After 14 days, severe effects could still be observed. Two animals showed ablation of skin and beginning scarring. One animal had a reddish lesion where the test material had been applicated.

Scoring for erythema and edema (maximum score = 4

Erythema

Edema

1 h

24 h

48 h

72 h

7 d

14 d

1 h

24 h

48 h

72 h

7 d

14 d

Rabbit 1

*

*

*

*

*

*

3

3

2

1

*

*

Rabbit 2

*

*

*

*

*

*

2

2

3

2

*

*

Rabbit 3

*

*

*

*

*

*

2

2

1

1

*

*

* scoring not possible due to severe skin hardening and discoloration

Applicant's summary and conclusion

Interpretation of results:

Category 1B (corrosive) based on GHS criteria

Remarks:

Migrated information R 34 Criteria used for interpretation of results: EU

Conclusions:

Butyric acid caused corrosion of the rabbit's skin after a 1-hour contact period

Executive summary:

In a valid GLP OECD 404 study 3 rabbits were exposed dermally to a single dose of 0.5 ml of undiluted TS for a period of one hour. Butyric acid was corrosive as evidenced by skin lesions, severe hardening and discolouring which persisted until the end of the 14 -day observation period (Hoechst AG, 1983).