3,7-dimethylocta-1,6-diene

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 27 July 2010 to 17 September 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study well conducted and in compliance with GLP

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Evaluation of the primary ocular irritation of Dimethyloctadiene after application on a human reconstituted corneal epithelium model and quantification of cellular viability by reduction test of MTT (Mosmann, T. 1983) and T50 determination, exposure time that causes 50% of mortality. This reconstituted corneal epithelium model could be consider as the most similar to the human corneal because it is a 3D model.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

3,7-dimethylocta-1,6-diene

EC Number:

219-433-3

EC Name:

3,7-dimethylocta-1,6-diene

Cas Number:

2436-90-0

Molecular formula:

C10H18

IUPAC Name:

3,7-dimethylocta-1,6-diene

Details on test material:

- Name of test material (as cited in study report): dimethyloctadiene
- Physical state: colourless translucent liquid
- Analytical purity: 91.1 %
- Impurities (identity and concentrations): 1-Isopropenyl-2,3-dimethyl-cyclopentane
- Purity test date: 31 March 2010
- Lot/batch No.: EC205R
- Expiration date of the lot/batch: 18 March 2011
- Storage condition of test material: kept in refrigerator under nitrogen flow, protected from light and humidity

Test animals / tissue source

Species:

human

Strain:

not specified

Test system

Vehicle:

unchanged (no vehicle)

Remarks:

dimethyloctadiene is tested at 100% (undiluted sample).

Controls:

other: negative control= untreated epithelium (epithelium in maintenance medium); positive control= Sodium Dodecyl Sulfate (CAS 151-21-3) at 0.5% (W/W) in sterile water

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 30 µL
- Concentration (if solution): the test item is applied as supplied (ie. undiluted)

VEHICLE: not applicable

Duration of treatment / exposure:

test item: 10 min, 60 and 180 min
Positive control: 10 and 60 min
Negative control: 180 min

Observation period (in vivo):

at the end of each incubation, the MTT test was performed immediately.

Number of animals or in vitro replicates:

all conditions (test item, negative control and positive control) were performed in duplicate

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): at the end of each incubation period rinsing of the epithelia under a jet of PBS (using a washing bottle), by possibly removing the excess product adhering to epithelium using a cotton-wool bud.
- Time after start of exposure: at the end of exposure time (10, 60, or 180 min)

SCORING SYSTEM: not applicable

TOOL USED TO ASSESS SCORE: not applicable

Results and discussion

In vitro

Results

Irritation parameter:

other: T50

Value:

>= 180

Any other information on results incl. tables

None

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the test conditions, Dimethyloctadiene is not classified as irritating to eyes.

Executive summary:

In an in vitro ocular primary irritation test, performed in compliance with GLP, human reconstructed corneal epithelium was treated with undiluted Dimethyloctadiene. The test substance was in contact with corneal epithelium for 10, 60 or 180 minutes and then the epithelia were rinsed.

MTT conversion assay was peformed to evaluate the percentage of cellular viability of the epithelium in order to caculate the T50, which is the time when 50% of the cells are dead.

Negative control (maintenance medium) and positive control (Sodium dodecyl sulfate) were also used and the results were acceptable for these controls.

The T50 for Dimethyloctadiene calculated from 3 contact time points was higher than 180 minutes. Therefore, under the test conditions, Dimethyloctadiene is not classified as irritating to eyes.