5(or 6)-methyl-7(or 8)-(1-methylethyl)bicyclo[2.2.2]oct-5-ene-2-carbaldehyde

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:

other: The study was performed to the standardised guidelines OECD 437 and EU Method B.47 and in line GLP. The study was reported to a high standard, sufficient to assess the quality of the data presented.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying Ocular Corrosives and Severe Irritants)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU method B.47 (Bovine corneal opacity and permeability test method for identifying ocular corrosives and severe irritants)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

8-isopropyl-6-methylbicyclo[2.2.2]oct-5-ene-2-carbaldehyde

EC Number:

267-308-7

EC Name:

8-isopropyl-6-methylbicyclo[2.2.2]oct-5-ene-2-carbaldehyde

Cas Number:

67845-30-1

Molecular formula:

C13H20O

IUPAC Name:

8-isopropyl-6-methylbicyclo[2.2.2]oct-5-ene-2-carbaldehyde

Constituent 2

Reference substance name:

7-isopropyl-5-methylbicyclo[2.2.2]oct-5-ene-2-carbaldehyde

EC Number:

299-795-7

EC Name:

7-isopropyl-5-methylbicyclo[2.2.2]oct-5-ene-2-carbaldehyde

Cas Number:

93904-56-4

Molecular formula:

C13H20O

IUPAC Name:

7-isopropyl-5-methylbicyclo[2.2.2]oct-5-ene-2-carbaldehyde

impurity 1

Reference substance name:

rel-(1S,2R,4R)-1-isopropyl-4-methylbicyclo[2.2.2]oct-5-ene-2-carbaldehyde

Cas Number:

36208-34-1

Molecular formula:

C13H20O

IUPAC Name:

rel-(1S,2R,4R)-1-isopropyl-4-methylbicyclo[2.2.2]oct-5-ene-2-carbaldehyde

Test material form:

liquid

Specific details on test material used for the study:

Test article: Maceal
CAS NumberL 68259-31-4
Storage: 2 - 8 °C
Batch Number: SC00008034
Expiration date: 11 December 2014
Purity: 99.2%

Test animals / tissue source

Species:

other: Bovine corneas

Test system

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied: 750 µL
- Concentration: Undiluted

Duration of treatment / exposure:

10 minutes

Observation period (in vivo):

1 hour 50 minutes

Number of animals or in vitro replicates:

Bovine corneas was used in place of live animals.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

other: Corneal opacity

Basis:

mean

Time point:

other: 1 hour 50 minutes

Score:

3.7

Reversibility:

not specified

Results 2

Irritation parameter:

other: Corneal permeability

Basis:

mean

Time point:

other: 85 minutes

Score:

0.013

Reversibility:

not specified

Irritant / corrosive response data:

CORNEAL OPACITY
Mean corrected opacity reading for test material: 3.7
Mean corrected opacity reading for negative control: 0.0
Mean corrected opacity reading for positive control: 21.3
The corneas treated with the positive control were cloudy following treatment.

CORNEAL PERMEABILITY
Mean corrected optical density for test material: 0.013
Mean corrected optical density for negative control: 0.000
Mean corrected optical density for positive control: 1.224

Any other information on results incl. tables

Table 1: Corneal Opacity

Test substance	Cornea No.	Initial Opacity	Post Incubation Opacity	Change in Opacity	Mean Change in Opacity	Corrected Opacity	Mean Corrected Opacity
Negative control (NaCl)	2	4	4	0	0.33	-0.3	0
	5	6	6	0		-0.3
	6	4	5	1		0.7
Test material	22	4	9	5	N/A	4.7	3.7
	32	4	7	3		2.7
	34	4	8	4		3.7
Positive control (100 % Ethanol)	11	3	25	22	N/A	21.7	21.3
	16	4	26	22		21.7
	17	2	23	21		20.7

 

Table 2: Corneal Permeability

Test substance	Cornea No.	Mean Blank OD490	OD490	Corrected OD490	Mean Corrected OD490	Final Corrected OD490
NaCl (negative control)	2	N/A	0.001	0.001	0.004	-0.002	0.000
	5		0.006	0.006		0.002
	6		0.003	0.003		0.000
Test material	22	0.000	0.025	0.025	N/A	0.021	0.013
	32		0.014	0.014		0.010
	34		0.010	0.010		0.006
100 % Ethanol (positive control)	11	N/A	1.042	1.042	N/A	1.039	1.224
	16		1.204	1.204		1.201
	17		1.436	1.436		1.432

 

 

Table 3: IVIS scores

Test substance	IVIS
Test material	3.86
NaCl (negative control)	0.00
100 % Ethanol (positive control)	39.69

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of the test, the test material produced an in vitro irritancy score (IVIS) of 3.86 in bovine corneas. Therefore a prediction cannot be made in respect of the potention for the test material to cause eye irritation.
However, based on the results of the animal experiement where no irritancy was observed, the substance is considered to be negative for in vitro eye irritation.

Executive summary:

The potential of the test material to cause serious eye irritation was investigated in vitro in a study conducted in accordance with the standardised guidelines OECD 437 and EU Method B.47 under GLP conditions using bovine corneas.

750 µL of undiluted test material was applied to each of three corneas and incubated for 10 minutes at 32 °C ± 1 °C. After incubation, each cornea was washed with media containing phenol red followed by media without phenol red and incubated horizontally for 1 hour 50 minutes and then measured for opacity.

Permeability of the corneas was measured by replacing the media in the anterior chamber with 1 mL of 4 mg/mL sodium fluorescein. The posterior chamber was filled with fresh media. The corneas were incubated vertically for 85 minutes at 32 °C ± 1 °C. The posterior chambers were the removed and three 350 µL aliquots of the media were taken for analysis of optical density at 490 nm.

The mean corrected opacity reading for the test material was determined to be 3.7. The mean corrected opacity reading for negative and positive controls was 0.0 and 21.3, respectively. The corneas treated with the positive control were cloudy following treatment.

The mean corrected optical density for the test material was determined to be 0.013. The mean corrected optical densities for negative and positive controls were 0.000 and 1.224, respectively.

Under the conditions of the test, the test material produced an in vitro irritancy score (IVIS) of 3.86 in bovine corneas. Therefore a prediction cannot be made in respect of the potention for the test material to cause eye irritation. However, based on the results of the animal experiement where no irritancy was observed, the substance is considered to be negative for in vitro eye irritation.