L-menthyl acetate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2012-05-14 to 2012-08-07

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study according to OECD TG 439

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)

Version / remarks:

2010

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.46 (In Vitro Skin Irritation: Reconstructed Human Epidermis Model Test)

Version / remarks:

2009

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Menthyl acetate

EC Number:

201-911-8

EC Name:

Menthyl acetate

Cas Number:

89-48-5

Molecular formula:

C12H22O2

IUPAC Name:

Menthyl acetate

In vitro test system

Justification for test system used:

Because systemic reactions play a minor role in modulating local skin toxicity potential of chemicals, skin irritation potential may be predicted by in vitro systems, provided they are sufficiently complex to mimic human skin barrier and cell reactivity. In an international prevalidation study performed by ECVAM, the in vitro skin irritation test using the human skin model EpiDerm™ and EpiSkin™ and measurement of cell viability by dehydrogenase conversion of MTT into a blue formazan salt have turned out as a sufficiently promising predictor for skin irritancy potential.

Test animals

Details on test animals or test system and environmental conditions:

not relevant

Test system

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 10 µL
- Concentration (if solution): undiluted

Duration of treatment / exposure:

15 min treatment + 42 h incubation

Number of animals:

not relevant

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes, with PBS
- Time after start of exposure: 15 min

SCORING SYSTEM:
In vitro result: In vivo prediction:
mean tissue viability ≤ 50 % → irritant (I), H315 (category 2)
mean tissue viability > 50 % → non-irritant (NI)

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

other: other: Relative Absorbance

Value:

105.3

Remarks on result:

other:

Remarks:

Basis: other: Test item on EpiSkin. Max. score: 100.0. Reversibility: no data. Remarks: % of negative control. (migrated information)

Any other information on results incl. tables

Results after treatment with menthyl acetate racemic and controls

Dose group	Treat-ment interval	Absor-bance 540 nm Tissue 1*	Absor-bance 540 nm Tissue 2*	Absor-bance 540 nm Tissue 3*	Mean Absorbance of 3 Tissue	Relative absor-bance [%] Tissue 1, 2+3**	Stan-dard De-viation [%]	Rel. Absor-bance [% of negative control]***
Negative Control	15 min	1.154	1.047	1.032	1.077	107.1 97.2 95.8	6.2	100.0
Positive Control	15 min	0.175	0.142	0.154	0.157	16.3 13.2 14.3	1.6	14.6
Test Item	15 min	1.175	1.050	1.178	1.134	109.0 97.5 109.4	6.8	105.3

*Mean of two replicate after blank correction

**Relative absorbance per tissue [rounded values]: 100xabsorbance (tissue)/mean absorbance (negative control)

***Relative absorbance per treatment group [rounded values]: 100xmean absorbance (test item)/mean anbsorbance (negative control)

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The mean relative absorbance value of the test item, corresponding to the cell viability, did not decrease (105.3%; threshold for irritancy: ≤ 50%), consequently the test item was non irritant to skin.

Executive summary:

This in vitro study was performed to assess the irritation potential of Menthyl Acetate racemic by means of the Human Skin Model Test according to OECD TG 439. Three tissues of the human skin model EpiSkin™ were treated with the test item, the negative or the positive control for 15 minutes. 10 μL of the liquid test item were applied to each tissue, spread to match the tissue size. 10 μL of either the negative control (deionised water) or the positive control (5% Sodium lauryl sulfate) were applied to each tissue. After treatment with the negative control the absorbance values were well within the required acceptability criterion of mean OD  0.6 till ≤ 1.5 for the 15 minutes treatment interval thus showing the quality of the tissues. Treatment with the positive control induced a sufficient decrease in the relative absorbance as compared to the negative control for the 15 minutes treatment interval thus ensuring the validity of the test system. Compared to the value of the negative control, after exposure of the test item Menthyl Acetate racemic the mean relative absorbance value did not decrease (105.3%; threshold for irritancy of ≤ 50%). Therefore, the test item is not considered to possess an irritant potential. In conclusion, it can be stated that in this study and under the experimental conditions reported, the test item Menthyl Acetate racemic is non irritant to skin according to UN GHS and EU CLP regulation.