Sodium 2-heptyl-2,3-dihydro-3-(2-hydroxyethyl)-1H-imidazole-1-propionate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

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:

The detailed method followed in this study is described in XCellR8 SOP L0069: ‘EpiOcularTM Eye Irritation Test (OECD TG492) and is based on the MatTek protocol (MK-24-007-0055, 10 Feb 17) using the MatTek Corporation EpiOcularTM reconstructed tissue model OCL-200. This protocol was approved as the new OECD TG492 at the 2015 meeting of the OECD Working Group of the National Coordinators for the Test Guidelines Programme

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Sodium 2-heptyl-2,3-dihydro-3-(2-hydroxyethyl)-1H-imidazole-1-propionate

EC Number:

271-928-3

EC Name:

Sodium 2-heptyl-2,3-dihydro-3-(2-hydroxyethyl)-1H-imidazole-1-propionate

Cas Number:

68630-95-5

Molecular formula:

C15H28N2O3.Na

IUPAC Name:

sodium 3-[2-heptyl-3-(2-hydroxyethyl)-2,3-dihydro-1H-imidazol-1-yl]propanoate

Test material form:

solid

Details on test material:

Product name: Crodateric CYAP
Batch Number: PS-196-555
Appearance: The sample has been produced from drying of the aqueous solution of the material as sold commercially. It is observed to be a brown sticky solid

Specific details on test material used for the study:

Supplier Croda
Test Item Name Crodateric CYAP-100
Supplier Code DEV080817DS3
Supplier batch/lot number PS-196-562
CAS number 70983-43-6
Purity 99.41% (from Sponsor Certificate of Analysis)
Expiry Date 3 July 2018
Physical state Solid, Dark, Brown
Storage Conditions Room Temperature
Solubility N/A - neat application
Administration method Topical application
Concentration tested Neat
XCellR8 test item code CRO1026
Study test item code TA1

Test animals / tissue source

Species:

human

Strain:

other: reconstructed tissue. MatTek’s EpiOcularTM system consists of normal, human-derived keratinocytes which have been cultured to form a stratified, squamous epithelium similar to that found in the cornea.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

After pre-wetting tissues with 20µl PBS (Sterile Dulbecco’s Phosphate Buffered Saline) for 30 ± 2 min, single topical application of nominal 50mg of neat test item, using a pin applicator or 50µl of reference items to the surface of the EpiOcularTM model for 6h ± 15 minutes, followed by a 25 ± 2 minutes’ post-treatment immersion, and 18 hours ± 15 minutes’ post-treatment incubation, prior to the MTT endpoint; three tissues per condition (n=3).

Duration of treatment / exposure:

After pre-wetting tissues with 20µl PBS (Sterile Dulbecco’s Phosphate Buffered Saline) for 30 ± 2 min, single topical application of nominal 50mg of neat test item, using a pin applicator or 50µl of reference items to the surface of the EpiOcularTM model for 6h ± 15 minutes, followed by a 25 ± 2 minutes’ post-treatment immersion, and 18 hours ± 15 minutes’ post-treatment incubation, prior to the MTT endpoint; three tissues per condition (n=3).

Details on study design:

The EpiOcularTM tissue model (OCL-200-MatTek Corporation) is composed of stratified human keratinocytes in a three-dimensional structure, reflecting the morphology and function of the human corneal epithelium found in vivo.
The EpiOcular™ Eye Irritation Test (EIT), using the MatTek EpiOcularTM tissue model OCL-200, was validated by the European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM) and Cosmetics Europe between 2008 and 2013. From this validation study and its independent peer review it was concluded that the EpiOcularTM EIT is able to correctly identify chemicals (both substances and mixtures) not requiring classification and labelling for eye irritation or serious eye damage according to UN GHS, and the test method was recommended as scientifically valid for that purpose, as an alternative to Draize Rabbit Eye Test with excellent correlation -In vivo to In vitro test results.

Results and discussion

In vitro

Results

Irritation parameter:

other: percentage of viability

Run / experiment:

The test item Crodateric CYAP-100 did not reduce the viability to 60% or below after 6h of application and should be considered as non-Irritant to the eye.

Value:

97.3

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

Prior to the study, the required compatibility checks (as per SOP L0069) show that the test item did interfere with MTT. However, OD obtained with the freeze-killed tissues were low (<0.1) and therefore they were not subtracted from OD values obtained during the main assay.

Any other information on results incl. tables

Mean and SD of viability measurements and of viability percentages after 6h (± 15 min) of application and 18h (± 15 min) post-incubation.

 

Name	Code	mean of OD	SD of OD	Mean of viability (%)	SD of viability (%)	CV %	Classification
Sterile water	NC	1.421	0.068	100.0	4.8	4.8	Non-Irritant
Methyl Acetate	PC	0.035	0.025	2.4	1.7	71.6	Irritant
CRODATERIC CYAP-100	TA1	1.383	0.098	97.3	6.9	7.1	Non-Irritant

 

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Interpretation of Results following Prediction Model
• A test item is considered to be irritant to the eye (i.e. would require labelling as either GHS 1 or 2) if the eye model viability after exposure and post-treatment incubation is ≤60%.
• A test item is considered as a non-irritant to the eye (i.e. would not require a warning label in the European chemical classification systems) if the eye model viability after exposure and post-treatment incubation is >60%.
The current assay is not intended to differentiate between GHS class 1 and GHS class 2 or R36 and R41 (degree of stromal damage).
The percentage of viability obtained with test item Crodateric CYAP-100 was 97.3%, therefore it has to be considered as Non- Irritant to the eye.