2,4,7-trimethyloct-6-en-1-ol

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2,4,7-trimethyloct-6-en-1-ol

EC Number:

814-338-9

Cas Number:

1913285-57-0

Molecular formula:

C11H22O

IUPAC Name:

2,4,7-trimethyloct-6-en-1-ol

Test material form:

liquid

In vitro test system

Test system:

human skin model

Source species:

other: human derived

Cell type:

non-transformed keratinocytes

Justification for test system used:

Recommended test system in international guidelines (OECD and EC).

Vehicle:

unchanged (no vehicle)

Details on test system:

EpiDerm Skin Model
The model consists of normal, human-derived epidermal keratinocytes which have been cultured to form a multilayered, highly differentiated model of the human epidermis. It
consists of organized basal, spinous and granular layers, and a multi-layered stratum corneum containing intercellular lamellar lipid layers arranged in patterns analogous to those found in vivo. The EpiDerm tissues (surface 0.6 cm²) were cultured on polycarbonate membranes of 10 mm cell culture inserts.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

The liquid test item was applied undiluted (50 μl) directly on top of the tissue.

Duration of treatment / exposure:

Two tissues were used for a 3-minute exposure to GR-50-3010 and two for a 1-hour
exposure.

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

1

Value:

135

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

2

Value:

127

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Two tissues were used for a 3-minute exposure to GR-50-3010 and two for a 1-hour exposure.

Executive summary:

GR-50-3010 was checked for color interference in aqueous conditions and possible direct MTT reduction by adding the test item to MTT medium. Because the solutions did not turn blue / purple nor a blue / purple precipitate was observed it was concluded that GR-50-3010

did not interfere with the MTT endpoint.

The mean absorption at 570 nm measured after treatment with GR-50-3010 and controls are presented in Appendix 2, Table 1.

Appendix 3.

Table 2 shows the mean tissue viability obtained after 3-minute and 1-hour treatments with GR-50-3010 compared to the negative control tissues. Skin corrosion is expressed as the remaining cell viability after exposure to the test item. The relative mean tissue viability obtained after the 3-minute and 1-hour treatments with GR-50-3010 compared to the negative control tissues was 135% and 127% respectively. Because the mean relative tissue viability for GR-50-3010 was not below 50% after 3 minutes treatment and not below 15% after 1 hour treatment GR-50-3010 is considered to be not corrosive.

The absolute mean OD570 (optical density at 570 nm) of the negative control tissues was within the acceptance limits of OECD 431 (lower acceptance limit ≥0.8 and upper acceptance limit 2.8) and the laboratory historical control data range. The mean relative tissue viability following the 1-hour exposure to the positive control was 9%.

In the range of 20 - 100% viability the Coefficient of Variation between tissue replicates was 2.3%, indicating that the test system functioned properly.