2-propylheptan-1-ol

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

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

Principles of method if other than guideline:

The test was conducted in accordance with the Standard Operating Procedure, In Vitro Skin Irritation Test: Human Epidermis Model (L'Oreal, 2005), supplied by L'Oreal (leading laboratory in the validation of the test for ECVAM) and the OECD Guideline For The Testing of Chemicals (OECD 2008).

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2-propylheptan-1-ol

EC Number:

233-126-1

EC Name:

2-propylheptan-1-ol

Cas Number:

10042-59-8

Molecular formula:

C10H22O

IUPAC Name:

2-propylheptan-1-ol

Test material form:

liquid

Specific details on test material used for the study:

- Name of test material (as cited in study report): 2-Propylheptan-1-ol
- Physical state: Clear, colourless liquid
- Analytical purity: 96.2%
- Lot/batch No.: 16.06.2008
- ID Nr.: 0649/82526
- Expiration date of the lot/batch: July 2009
- Storage condition of test material: Room temperature

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Vehicle:

unchanged (no vehicle)

Details on test system:

SKIN DISC PREPARATION
- Procedure used: The maintenance medium was pre-warmed to 37° C. The tissues were removed from the agar and placed into wells of 12 well plates containing 2 ml pre-warmed maintenance medium per well. The tissues were incubated for a minimum of 24 hours at 37 ± 2°C in a humidified atmosphere of 5% C02 in air.
- Quality control for skin discs:histological scoring(HES stained vertical paraffin sections, n = 6): well-dlfferentiated epidermis consisting of a basal layer, several spinousand granular layers and a thick stratum corneum; IC50 determination (after SDS treatment)

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: 37 ± 2°C
- Temperature of post-treatment incubation (if applicable): 37 ± 2°C

REMOVAL OF TEST MATERIAL AND CONTROLS
- Number of washing steps: 1
- Observable damage in the tissue due to washing: not specified
- Modifications to validated SOP: no

DYE BINDING METHOD
- Dye used in the dye-binding assay: MTT
- Spectrophotometer: not specified
- Wavelength: 540 nm
- Filter: not specified
- Filter bandwidth: not specified

NUMBER OF INDEPENDENT TESTING RUNS / EXPERIMENTS TO DERIVE FINAL PREDICTION: 1

PREDICTION MODEL / DECISION CRITERIA
If the mean tissue viability was equal or less than 50% of the negative control value, the sample was classed as Irritant R38 (EU classification).

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

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

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

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 10 µL
- Concentration (if solution): 5% in sterile water

Duration of treatment / exposure:

15 ± 0.5 minutes

Duration of post-treatment incubation (if applicable):

42 ± 1 hour

Number of replicates:

3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Value:

10.9

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

positive indication of irritation

Other effects / acceptance of results:

- OTHER EFFECTS:
- Visible damage on test system: not specified
- Direct-MTT reduction: no
- Colour interference with MTT: no

DEMONSTRATION OF TECHNICAL PROFICIENCY: yes

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: yes
- Acceptance criteria met for positive control: yes
- Acceptance criteria met for variability between replicate measurements: yes

Any other information on results incl. tables

- Negative control:

The mean absorbance of the triplicate negative control values was 0.618 which was above the minimum acceptance value of 0.6. The standard deviation of the % viability was 2.8 which was below the maximum acceptance value of 18.

- Positive control: The mean viability of the positive control was 12.5% ± 6.0 of the negative control. These were below the maximum acceptance values of 30% viability and SD of 18.

There was no colour change in the test substance, 2-Propylheptan-l-ol (MTT) solution or the water control (MTT) solution after three hours incubation in the dark at 37 ±2°C in a humidified atmosphere of5% CO2 in air. The test substance had not interacted with the MTT.

Sample	Tissue viability as percentage of mean OD negative control
	Replicate Tissues			Mean +/- SD	Prediction MTT endpoint
Negative Control	102.7	100.2	97.1	100.0 +/- 2.8	not applicable
Positive control	7.7	19.3	10.4	12.5 +/- 6.0	irritant
2-Propylheptan-I-ol	14.7	8.1	9.9	10.9 +/- 3.4	irritant

The Standard Operating Procedure, In Vitro Skin Irritation Test: Human Epidermis Model EPISKIN, EPISKIN Skin Irritation Test-42hours (L'Oreal 2005) recommends analysis of IL-1alpha if the MTT mean tissue viability of the test material is >/= 50%. As the mean tissue viability of test material, 2-Propylheptan-1-ol, was 10.9 % ± 3.4, IL-1 alpha analysis of the medium was not required.

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Conclusions:

It was concluded that the test material with a mean tissue viability of 10.9 % ± 3.4, is predicted as a skin irritant.

Executive summary:

The objective of the test was to assess the skin irritancy, in vitro, of the test substance.

The test material was applied to EPISKIN human epidermis skin constructs. The constructs consisted of normal, human-derived epidermal keratinocytes, which had been cultured to form a multilayered, highly differentiated model of the human epidermis with a functional multilayered stratum corneum. The cell viability of the multi layers was determined by mitochondrial dehydrogenase activity. The prediction model uses the percentage viability values (compared to negative control viability) to identify irritant and non-irritant materials.

The test material elicited a mean tissue viability of 10.9 ±3.4 % and was predicted as irritant.