Registration Dossier

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:
2012
Report Date:
2012

Materials and methods

Test guideline
Qualifier:
according to
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)
Deviations:
no
Remarks:
Conducted according to guideline in effect at time of study conduct
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Purity: 22.82% solids in water

Test system

Details on study design:
Bovine corneas, obtained as a by-product from freshly slaughtered animals, were mounted in special holders and exposed to the test substance. An in vitro score was determined for the test substance based on the induction of opacity and permeability (to fluorescein) in the isolated bovine corneas. The positive control was ethanol and the negative control was sterile, deionized water. The test substance was administered to the test system without dilution.
Opacity measurement: Opacity was determined for each cornea using an Electro Design OP-KIT opacitometer. The change in opacity for each cornea (including the negative control corneas) was calculated by subtracting the initial opacity reading from the final opacity reading. These values were then corrected by subtracting from each the average change in opacity observed for the negative control corneas. The mean opacity value of each treatment group was calculated by averaging the corrected opacity values of each cornea for that treatment condition.
Permeability Measurement: The mean OD490 value for the blank wells was calculated. The mean blank OD490 value was then subtracted from the raw OD490 values of each well (corrected OD490). Any dilutions that were made to bring the OD490 readings into the linear range of the platereader (OD490 should be less than 1.500), had each diluted OD490 reading multiplied by the dilution factor. The final corrected OD490 value of the test substance and the positive control was then calculated by subtracting the average corrected OD490 value of the negative control corneas from the corrected OD490 value of each treated cornea. The mean OD490 value of each treatment group was calculated by averaging the final corrected OD490 values of the treated corneas for that treatment condition. The in vitro score was determined:
In Vitro Score = Mean Opacity Value + (15 x Mean OD490 Value).

Results and discussion

In vitro

Results
Irritation parameter:
in vitro irritation score
Value:
1.7
Vehicle controls validity:
valid
Positive controls validity:
not valid

In vivo

Irritant / corrosive response data:
Table 1 summarizes the opacity, permeability, and in vitro score for the test substance and positive control. Since the results of the positive control (ethanol) fell within two standard deviations of the historical mean (within a range of 39.2 to 64.0), the assay was considered valid.
Following the classification established by Gautheron et al. (1992) (Sina classification system) based on studies with a wide range of test materials, the test substance, would be considered a mild irritant. Following the modification of the Sina classification system proposed by Vanparys, et al. (1993) based on an evaluation of 50 pharmaceutical and commercially-available industrial compounds, the test substance would be considered a non-irritant.

Sina classification system
In vitro score:
from 0 to 25 = mild irritant
from 25.1 to 55 = moderate irritant
from 55.1 and above = severe irritant

Vanparys, et al modification of Sina classification system
In vitro score:
from 0 to 3 = non irritant
from 3.1 to 25 = mild irritant
from 25.1 to 55 = moderate irritant
from 55.1 and above = corrosive/severe irritant

Any other information on results incl. tables

Table 1 BCOP Results 

 

Exposure time

Mean opacity value

Mean OD490 value

In vitro score

pH

Test substance

10 minutes

1.7

0.001

1.7

8.0

Positive control (Ethanol)

10 minutes

30.7

1.015

45.9

 

 

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
The study and the conclusions which are drawn from it fulfil the quality criteria (validity, reliability, repeatability).
Non-irritant to eyes.
Executive summary:

The Bovine Corneal Opacity and Permeability Assay was used to assess the potential ocular irritancy of the test substance as measured by changes in opacity and permeability (to fluorescein) in isolated bovine corneas. Based on changes in corneal opacity and permeability (relative to the control corneas), an in vitro score was determined. The in vitro score was 1.7 Since the results of the positive control (ethanol) fell within two standard deviations of the historical mean (within a range of 39.2 to 64.0), the assay was considered valid. Following the classification established by Gautheron et al. (1992) (Sina classification system) based on studies with a wide range of test materials, the test substance, would be considered a mild irritant (in vitro score from 0 to 25). Following the modification of the Sina classification system proposed by Vanparys, et al. (1993) based on an evaluation of 50 pharmaceutical and commercially-available industrial compounds, the test substance would be considered a non-irritant (in vitro score from 0 to 3).