p-menth-1-en-4-ol

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

publication

Title:

Correlations of the components of tea tree oil with its antibacterial effects and skin irritation

Author:

Lee C. J., Chen L. W., Chen L. G., Chang T. L., Huang C. W., Huang M. C., Wang C. C.

Year:

2013

Bibliographic source:

Journal of Food and Drug analysis 21 (2013) 169-176

Report date:

2013

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

- Principle of test: Draize skin irritation test as described in Draize et al. (1944) Methods for the study of irritation and toxicity of substances applied topically to the skin and mucous membranes; Journal of Pharmacology and Experimental Therapeutics, Nov 1944, 82 (3) 377-390
- Parameters analysed / observed: erythema and oedema using a scoring system by Draize et al. (1944)

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

p-menth-1-en-4-ol

EC Number:

209-235-5

EC Name:

p-menth-1-en-4-ol

Cas Number:

562-74-3

Molecular formula:

C10H18O

IUPAC Name:

4-methyl-1-(propan-2-yl)cyclohex-3-en-1-ol

Test material form:

liquid

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source: Sigma Aldrich, Milan, Italy
- Purity: analytical-grade

Test animals

Species:

rat

Strain:

Wistar

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: BioLASCO, Taiwan
- Age at study initiation: 8-10 weeks
- Females non-pregnant and nulliparous: yes
- Weight at study initiation: 200-220
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: not specified

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 25 +/- 1
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Type of coverage:

not specified

Preparation of test site:

shaved

Vehicle:

not specified

Controls:

not specified

Amount / concentration applied:

Amount applied: 50 µl
Concentrations: 0.094%, 0.188%, 0.375%, 0.750%, 1.500%

Duration of treatment / exposure:

4 h

Observation period:

24, 48 h

Number of animals:

Each group consisted of five female rats

Details on study design:

TEST SITE
- Area of exposure: 2.5 x 2.5 cm at each site of the back
- Site preparation: 24 h before the test, the backs of the animals were shaved and checked for any abnormalities the next day.

REMOVAL OF TEST SUBSTANCE
- Washing: with distilled water
- Time after start of exposure: 4 h

OBSERVATION TIME POINTS
- 24 and 48 h

SCORING SYSTEM:
- Method of calculation: Scoring system by Draize et al. (1944)

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48 h

Score:

0

Max. score:

4

Reversibility:

other: no evidence of any skin reaction

Remarks on result:

no indication of irritation

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48 h

Score:

0

Max. score:

4

Reversibility:

other: no evidence of any skin reaction

Remarks on result:

no indication of irritation

Any other information on results incl. tables

The prepared tea tree oil from leaves and from twigs contained 47.31% and 39.09% terpinen-4 -ol, respectively.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions chosen, the test substance did not induce skin irritancy.

Executive summary:

Five female Wistar rats per concentration group were treated with 0.094%, 0.188%, 0.375%, 0.750%, 1.500% of terpinen-4 -ol. Exposure duration was 4 hours and the test substance was removed with distilled water after the exposure period. Twenty-four and 48 h after application, skin irritation was observed and quantified through the scoring system by Draize et al. (1944). No evidence of erythema, oedema, or any other skin reaction was observed at 24 h and 48 h.