Octadecyl 3-mercaptopropionate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 August 2022 - 04 August 2022

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2022

Report date:

2022

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: Commission Regulation (EC) No 2019/1390, Annex Part B, B.69: “Reconstructed human cornea-like epithelium (RhCE) test method for identifying chemicals not requiring classification and labelling for eye irritation or serious eye-damage”

Version / remarks:

dated July 31st, 2019

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 492 (Reconstructed Human Cornea-like Epithelium (RhCE) Test Method for Identifying Chemicals Not Requiring Classification and Labelling for Eye Irritation or Serious Eye Damage)

Version / remarks:

18 June 2019

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Octadecyl 3-mercaptopropionate

EC Number:

250-801-6

EC Name:

Octadecyl 3-mercaptopropionate

Cas Number:

31778-15-1

Molecular formula:

C21H42O2S

IUPAC Name:

octadecyl 3-sulfanylpropanoate

Test animals / tissue source

Species:

human

Details on test animals or tissues and environmental conditions:

- Justification of the test method (e.g. ICE, EIT, RhCE) and considerations regarding applicability:
The use of the EpiOcularTM cultures offers features appropriate to model ocular irritation, because the model is composed of stratified human keratinocytes in a three-dimensional structure, and test materials can be topically applied to the model so that water insoluble materials may be tested. The epidermal cells, which are cultured on specially prepared cell culture inserts using serum-free medium, differentiate to form a multi-layered structure which closely parallels the corneal epithelium. The EpiOcular tissue model exhibits in vivo-like morphological and growth characteristics which are uniform and highly reproducible. Initial testing with standardized test materials shows a high level of correlation between in vivo and in vitro results.

- Product: EpiOcularTM Reconstructed ocular tissue Model
- Cell source: All cells used to produce EpiOcularTM are purchased or derived from tissue obtained by MatTek Corporation from accredited institutions. Consent was obtained by these institutions from the donors for use of the tissues or derivatives of the tissues for
research purposes.
- Lot number (living tissues): 34977
- Keratinocyte strain (living tissues): 4F1188
. Product: EpiOcularTM Reconstructed ocular tissue Model, frozen tissue
- Cell source: All cells used to produce EpiOcularTM are purchased or derived from tissue obtained by MatTek Corporation from accredited institutions. Consent was obtained by these institutions from the donors for use of the tissues or derivatives of the tissues for research purposes.
- Lot number (living tissues): 34926
- Keratinocyte strain (living tissues): 4F1188

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

50 μL of negative / positive control; 50 mg of test item

Duration of treatment / exposure:

6 hr ± 15 minutes

Duration of post- treatment incubation (in vitro):

18 hours±15 minutes

Number of animals or in vitro replicates:

2 (test item, positive and negative control items and killed functional control tissues in the same run)

Details on study design:

- 1 mg/mL MTT solution; 0.3 mL of MTT solution per well, 3 h incubation
- Wavelength used for quantifying MTT formazan: 570 nm (plate reader)

- This prediction model is applicable to all chemicals and can be used for the classification of all classes of chemicals. For each test chemical, the mean optical density (OD) of two treated tissues is determined and expressed as relative percentage of viability of the negative control. Tissues treated with eye irritants (GHS class 1 or 2) have relative viability of ≤ 60%, while treatment with non-irritants (No Category according to GHS) show viability > 60%.

Results and discussion

In vitro

Results

Irritation parameter:

percent tissue viability 

Value:

80.8

Negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Following exposure with the test item, the killed control corrected mean cell viability was 80.8%1 after the 6 hours exposure, compared to the concurrent negative control. This is above the threshold of 60%, therefore the test item was considered as being non irritant according to OCL-200-EIT classification, and no prediction can be made according to the UN GHS/EU CLP Classification.
In conclusion, in this in vitro EpiOcular™ Eye Irritation Test, the results indicate that the test item is not irritative to the eye.

Executive summary:

An in vitro eye irritation test with ODMP was performed in a reconstructed human epidermis model. EpiOcularTM Eye Irritation Test (OCL-200-EIT) is designed to predict and classify the irritancy potential of chemicals by measuring its cytotoxic effect as reflected in the MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The irritating potential of the test item was evaluated according to the OECD No. 492 guideline.
Two tissues per chemicals (the test item, positive and negative controls, furthermore the functional killed controls) were treated for 6 hours. Exposure of test material was terminated by rinsing with DPBS solution. The viability of each tissue was assessed by incubating the tissues
for 3 hours with MTT solution. The precipitated formazan crystals were then extracted using an extractant (isopropanol) and then quantified spectrophotometrically at 570±10 nm.
Sterile deionized water and Methyl acetate treated tissues were used as negative and positive controls, respectively (two tissues per compound). For each treated tissue, cell viability was expressed as a % relative to the concurrent negative control.
Following exposure with the test item, the killed control corrected mean cell viability was 80.8%1 after the 6 hours exposure, compared to the concurrent negative control. This is above the threshold of 60%, therefore the test item was considered as being non irritant according to OCL-200-EIT classification, and no prediction can be made according to the UN GHS/EU CLP Classification. The experiment met all the validity criteria, therefore the study was considered to be valid.
In conclusion, in this in vitro EpiOcular™ Eye Irritation Test, the results indicate that the test item is not irritative to the eye.