3-(heptyloxy)propane-1,2-diol

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 July 2019 - 05 July 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

28 July 2015

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

3-(heptyloxy)propane-1,2-diol

Cas Number:

10305-39-2

Molecular formula:

C10H22O3

IUPAC Name:

3-(heptyloxy)propane-1,2-diol

Test material form:

liquid

Details on test material:

Physical description: Clear to yellowish liquid
Storage conditions: Room temperature

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

foreskin from multiple donors

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: SkinEthic RHE / Human Epidermis (RHE/S/17)
- Tissue batch number(s): 19-RHE-113
- Surface: 0.5 cm2

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during exposure to the test item: room temperature
- Temperature of incubations(°C): 37%
- Humidity(%): 95%

REMOVAL OF TEST MATERIAL AND CONTROLS
- Volume and number of washing steps: tissues were washed with phosphate buffered saline (1 washing step)

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE:
- Incubation time: 3 hours +/- 5 minutes at 37 °C
- Measurement method: Visual assessment
- MTT concentration: 0.3 mg/mL in SkinEthic maintenance medium

NUMBER OF REPLICATE TISSUES: 3 tissues per test item, negative and positive controls.

PREDICTION MODEL / DECISION CRITERIA (see table 1)
The irritation potential of test item is predicted by the mean tissue viability of tissues exposed to the test item
- The test item is considered to be Category I or 2 if the mean relative viability after 42 minutes exposure and 42 hours post incubation is lower than or equal to 50% of the negative control.
- The test item is considered to be non irritant to skin, if the mean relative viability after 42 minutes exposure and 42 hours post incubation is higher than 50% of the negative control.

ACCEPTABILITY CRITERIA
- Blank (extraction solvent): The mean absorbances must be lower than 0.1.
- Negative control: The mean Absorbances must be higher than or equal to 0.8 and lower than or equal to 3.0. The standard deviation of the measured viabilities must be lower than or equal to 18%.
- Positive control: The viability percentage for the positive control must be lower than 40%. The standard deviation of the measured viabilities must be lower than or equal to 18%.
- Test item: The standard deviation measured viabilities must be lower or equal to 18%.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount applied: 16 +/- 0.5 µL (a 7.5 mm diameter (0.5 cm2) nylon mesh was gently applied after application of the substance on the surface of the epidermis)

NEGATIVE CONTROL
- Amount applied: 16 +/- 0.5 µL (a 7.5 mm diameter nylon mesh was gently applied after application of the substance on the surface of the epidermis)

POSITIVE CONTROL
- Amount applied: 16 +/- 0.5 µL (a 7.5 mm diameter nylon mesh was gently applied after application of the substance on the surface of the epidermis)

Duration of treatment / exposure:

42 +/- 1 minute

Duration of post-treatment incubation (if applicable):

42 hours; + 3 hours with MTT

Number of replicates:

3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Mean of 3 replicates

Value:

66.8

Negative controls validity:

valid

Positive controls validity:

valid

Remarks:

Mean tissue viability(%): 1.8

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

OTHER EFFECTS:
- Direct-MTT reduction: no
- Colour interference with MTT: no

ACCEPTANCE OF RESULTS:
- Validity criteria met for the blank control: Yes, the mean absorbances was 0.036.
- Acceptance criteria met for negative control: Yes, the absolute mean absorbanceof the negative control tissues was between 1.552 and 1.895 and the SD of the viability was 10.2%
- Acceptance criteria met for positive control: Yes, the mean relative tissue viability was 1.8% and the SD of the viability was 0.6%.
- Acceptance criteria met for variability between replicate measurements: Yes, the variability between tissue treated with the test item was 5%.

Applicant's summary and conclusion

Interpretation of results:

other: Not classified

Remarks:

According to Regulation (EC) No. 1272/200

Conclusions:

In an in vitro skin irritation test performed according to OECD guideline 439 and in accordance with GLP principles the substance showed to be a non-irritant (mean tissue viability of 66.8%).

Executive summary:

An in vitro skin irritation test using a human skin model was performed according to OECD TG 439 and in accordance with GLP principles. The test substance (16 +/- 0.5 µL ) was applied and covered with a nylon mesh. After 42 minutes, the substance was removed and cells were cultured for 42 hours. The viability of the cells was tested by reduction of MTT. Survival of unexposed skin was set at 100%, the positive control had a mean cell viability of 1.8% and the test substance showed a mean cell viability of 66.8%. Since the mean tissue viability for the test item was above 50% after treatment the test item is considered to be a non-irritant. In conclusion, Saskine 70 is a non-irritant in the in vitro skin irritation test under the experimental conditions described and should not be classified according to Regulation (EC) No. 1272/2008 and its amendments.