Bis(2-chloroethoxy)methane

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

25-Aug-2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study has been performed according to OECD and/or EC guidelines and according to GLP principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: OECD; Draft Proposal for a new guideline: "Bovine corneal opacity and permeability (BCOP) test method for identifying ocular corrosives and severe irritants

Deviations:

no

Principles of method if other than guideline:

- The Ocular Toxicity Working Group (OTWG) of the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) and the National Interagency Centre for the Evaluation of Alternative Toxicological Methods (NICEATM), Background Review Document (BRD): current status of in vitro test methods for identifying ocular corrosives and severe irritants: The Bovine Corneal Opacity and Permeability (BCOP) Test Method, March 2006

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Bis(2-chloroethoxy)methane

EC Number:

203-920-2

EC Name:

Bis(2-chloroethoxy)methane

Cas Number:

111-91-1

Molecular formula:

C5H10Cl2O2

IUPAC Name:

1-chloro-2-[(2-chloroethoxy)methoxy]ethane

Details on test material:

- Name of test material (as cited in study report): Diformal
- Substance type: Clear yellowish liquid
- Physical state: Liquid
- Stability under test conditions: Stable
- Storage condition of test material: At room temperature in the dark under nitrogen

Test system

Vehicle:

unchanged (no vehicle)

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 750 µl per cornea


POSITIVE CONTROL
- Amount(s) applied (volume or weight with unit): 750 µl Benzalkonium Chloride per cornea
- Concentration (if solution): 10% (w/v)
- Lot/batch no. (if required): S4214644 442

- Amount(s) applied (volume or weight with unit): 750 µl ethanol per cornea
- Lot/batch no. (if required): K40023527920

Duration of treatment / exposure:

- Treatment period: 10 minutes
- Incubation period: 2 hours

Details on study design:

TEST SITE
- Isolated bovine cornea

REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes
- Time after start of exposure: 10 minutes

SCORING SYSTEM:
- After exposure the cornea is thoroughly rinsed to remove the test substance and incubated for 2 hours with fresh medium followed by opacity measurement and the permeability of the corneas was determined after a 90 minutes incubation period with sodium fluorescein.
- - The mean opacity and mean permeability values (OD490) were used for each treatment group to calculate an in vitro score:

In vitro irritancy score (IVIS) = mean opacity value + (15 x mean OD490 value).

TOOL USED TO ASSESS SCORE:
- opacitymeter and fluorescein

DATA EVALUATION:
In vitro score range / In vitro classification
0 - 3 / Non irritant
3.1 - 25 / Mild irritant
25.1 - 55 / Moderate irritant
55.1 - 80 / Severe irritant
> 80 / Very severe irritant

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Run / experiment:

10 minutes exposure /120 minutes incubation

Value:

9

Remarks on result:

other: not reversible

Applicant's summary and conclusion

Interpretation of results:

other: mild irritant

Remarks:

Criteria used for interpretation of results: expert judgment

Conclusions:

The mean in vitro irritancy score (uncorrected) obtained with the negative control was less than 3.1 indicating that the negative controls did not induce irritancy on the corneas. The mean in vitro irritancy score of the positive control (10% w/v Benzalkonium Chloride) was 159 and was within the historical positive control data range (Appendix II, Table 6). The mean in vitro irritancy score of the second positive control (Ethanol) was 77 and was just above the values indicated in the draft proposal for a new guideline of the OECD (section 3.3 Guidelines, IVIS = 39.9 – 65.4). It was therefore concluded that the test conditions were adequate and that the test system functioned properly.

Diformal induced mild ocular irritation mainly on the opacity endpoint, resulting in a mean in vitro irritancy score of 9.0 after 10 minutes of treatment.

Finally, it is concluded that this test is valid and that Diformal is a mild irritant in the Bovine Corneal Opacity and Permeability test under the experimental conditions described in this report.