Neodecanoic acid, iron salt

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-09-05 to 2017-10-19

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 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage)

Version / remarks:

adopted 26 July 2013

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Neodecanoic acid, iron salt

EC Number:

257-446-6

EC Name:

Neodecanoic acid, iron salt

Cas Number:

51818-55-4

Molecular formula:

C10H20O2.xFe

IUPAC Name:

λ²-iron(2+) bis(2-ethyl-2,5-dimethylhexanoate)

Test material form:

solid

Details on test material:

- CAS Number: 51818-55-4
- EC Number: 257-446-6
- Molecular formula: C30H57FeO6
- Molecular weight: 569.6 g/mol
- Purity: 100%
- Storage conditions: Refrigerated under Nitrogen (2-8 °C)

Specific details on test material used for the study:

- Storage: 2 to 8 °C, under nitrogen
- Batch Number: LN11013894
- Retest Date: 31 July 2019
- Purity: 100%

Test animals / tissue source

Species:

cattle

Strain:

not specified

Details on test animals or tissues and environmental conditions:

- Corneas from bovine eyes were obtained from a local abattoir. The eyes were removed after slaughter, completely immersed in Hanks’ Balanced Salt Solution (containing penicillin at 100 IU/mL and streptomycin at 100 µg/mL) in a suitably sized container and transported on the same day to the testing facility.

- On arrival at the test facility the eyes were carefully examined for defects including increased opacity, scratches and neovascularisation. Only corneas free from such defects were used.

- Upon arrival at the test facility, the corneas were excised from the eyes and loaded onto the specifically designed holders. Both chambers of each holder were filled with pre-warmed Minimal Essential Medium (MEM), with the posterior chamber filled first, ensuring that no bubbles were formed. The holders were incubated at 32 ± 1 °C for at least 1 hour. After the incubation, the media was removed from both the anterior and posterior chambers. Fresh media was added to the posterior chamber first and then the anterior chamber (this media replacement order ensured the cornea retained its natural curvature as much as possible). The opacity of each cornea was measured using an opacitometer. Any corneas found to have scratches or increased neovascularization or an opacity of >7 opacity units when examined prior to treatment were discarded.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes

Amount / concentration applied:

- A volume of 750 µL of the test article was applied to each of three corneas.
- A volume of 750 µL of the negative or positive control was similarly applied to further groups of three corneas. These groups were subject to the procedures detailed above.

Duration of treatment / exposure:

A volume of 750 µL of the test article was applied to each of three corneas followed by a ten minute incubation at 32 °C. After this incubation period, each cornea was washed with media containing phenol red (as a pH indicator) until this indicator showed no pH change (demonstrating that the test article had been removed successfully). The corneas were then washed once in media without phenol red and the anterior chamber was filled with fresh MEM.
The corneas were incubated (horizontally) for 2 hours after which, corneal opacity was measured and then the anterior chamber was emptied. For the permeability endpoint, 1 mL of sodium fluorescein (4 mg/mL solution) was added into the anterior chamber and the corneas were incubated in the vertical position for 1 hour and 25 minutes. Following this period, the media in the posterior chamber was removed and held in a labelled tube. Three 350 µL aliquots of this media (per cornea) were analysed for optical density at 490 nanometers (OD490) using a spectrophotometer. A volume of 750 µL of the negative or positive control was similarly applied to further groups of three corneas. These groups were subject to the procedures detailed above.

Number of animals or in vitro replicates:

three corneas

Details on study design:

- Terminal Procedures: At the end of the assay all corneas were preserved in 10% Neutral Buffered Formalin. However, the Sponsor confirmed that microscopic examination was not required. The corneas were discarded on finalisation of the study report.

Results and discussion

In vitro

Results

Irritation parameter:

cornea opacity score

Run / experiment:

mean

Value:

0.44

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Remarks:

It was concluded that the test item produced an IVIS score of 0.44 and does not require classification for eye irritation.

Other effects / acceptance of results:

The assay was considered valid as the assay acceptance criteria were met.

Any other information on results incl. tables

Corneal Opacity

- The mean corrected opacity reading for the test article was 0.3.

- The mean corrected opacity reading for the negative control was 0.0.

- The mean corrected opacity reading for the positive control was 61.7.

- One cornea dosed with the test article was noted to be slightly cloudy after treatment. The corneas dosed with the positive control were noted to be cloudy and blistered after treatment.

Corneal Permeability

- The mean group corrected optical density for the test article was 0.007.

- The mean group corrected optical density for the negative control was 0.000.

- The mean group corrected optical density for the positive control was 0.394.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Based on an IVIS score of 0.44 obtained in the bovine corneal opacity and permeability assay (BCOP, OECD 437), the test item is considered as non-irritant to the eye.

Executive summary:

This study was conducted in accordance with OECD test guideline 437 to determine whether the test article causes serious eye damage or does not require classification for eye irritation, using the bovine corneal opacity and permeability (BCOP) assay. A mean in vitro irritation score (IVIS) of 0.44 was determined. The positive and negative controls induced the appropriate responses, indicating the validity of the assay. Based on the results, the test item can be considered as non-irritant to the eye and no classification is warranted.