7-(4-ethyl-1-methyloctyl)quinolin-8-ol

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

26 September 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2019

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 (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

7-(4-ethyl-1-methyloctyl)quinolin-8-ol

EC Number:

277-531-1

EC Name:

7-(4-ethyl-1-methyloctyl)quinolin-8-ol

Cas Number:

73545-11-6

Molecular formula:

C20H29NO

IUPAC Name:

7-(5-ethylnonan-2-yl)quinolin-8-ol

Test material form:

liquid

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Sponsor/1702-18-01/O
- Expiration date of the lot/batch: 25 Mar 2021
- Purity test date: 26 Mar 2018

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature (20 ± 5 °C); Keep away from light
- Stability under test conditions: Stable
- Solubility and stability of the test substance in the solvent/vehicle: Stable

Test animals / tissue source

Species:

cattle

Strain:

not specified

Details on test animals or tissues and environmental conditions:

SOURCE OF COLLECTED EYES
- Source: slaughterhouse Müller Fleisch GmbH, Enzstr. 2-4, 75217 Birkenfeld, Germany
- Number of animals: not specified.
- Characteristics of donor animals (e.g. age, sex, weight): The cattle were between 12 and 60 months old
- Storage, temperature and transport conditions of ocular tissue (e.g. transport time, transport media and temperature, and other conditions): The eyes were transported to the test facility in Hanks’ Balanced Salt Solution with 1% Penicillin-Streptomycin solution (Penicillin 100 U/mL, Streptomycin 100 µg/mL) in a suitable cooled container within 1 hour and 15 minutes.

Test system

Vehicle:

Hank's balanced salt solution

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 750 µL

Duration of treatment / exposure:

incubation time: 10 min

Duration of post- treatment incubation (in vitro):

2 hours

Number of animals or in vitro replicates:

3 replicates

Details on study design:

SELECTION AND PREPARATION OF CORNEAS : Only corneas which were free from damage were used. The corneas were excised with a scalpel and cut from the globe with a 2-3 mm ring of sclera around the outside. Each cornea was transferred to a cornea holder in which pre-warmed cMEM (32 ± 1 °C) without phenol red was filled. The holders were then incubated for 1 hour in the incubation chamber at 32 ± 1 °C.

QUALITY CHECK OF THE ISOLATED CORNEAS : After the initial incubation, the medium was completely changed and the baseline opacity for each cornea was recorded. None of the corneas showed tissue damage; therefore, all corneas were used.

NUMBER OF REPLICATES : 3

NEGATIVE CONTROL USED : HBSS

POSITIVE CONTROL USED : Dimethylformamide (undiluted)

APPLICATION DOSE AND EXPOSURE TIME : 750 µL, EXPOSURE TIME 10 MINUTES.

TREATMENT METHOD: closed chamber

POST-INCUBATION PERIOD: yes. If YES please specify duration : 2 hours.

REMOVAL OF TEST SUBSTANCE
- Number of washing steps after exposure period: the anterior chamber was rinsed with cMEM with phenol red, then with cMEM without phenol red.


METHODS FOR MEASURED ENDPOINTS:
- Corneal opacity: Opacitometer
- Corneal permeability: passage of sodium fluorescein dye measured with the aid of microtiter plate reader (OD 492 nm)

SCORING SYSTEM: In Vitro Irritancy Score (IVIS)
The IVIS of each replicate of the negative control was calculated from the following equation:
IVIS = opacity difference + (15 x corrected OD492 value)

The IVIS of each replicate of the positive control and of the test item were calculated from the following equation:
IVIS = (opacity difference – mean opacity difference of the negative control) + [15 x (OD492 – mean OD492 of the negative control)]

DECISION CRITERIA: OECD TG.

Results and discussion

In vitro

Results

Results 1

Irritation parameter:

in vitro irritation score

Run / experiment:

1

Value:

0.21

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation parameter:

in vitro irritation score

Run / experiment:

2

Value:

-1.44

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Results 3

Irritation parameter:

in vitro irritation score

Run / experiment:

3

Value:

0.75

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Results 4

Irritation parameter:

in vitro irritation score

Run / experiment:

mean

Value:

-0.16

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

OTHER EFFECTS:
- Visible damage on test system: none

DEMONSTRATION OF TECHNICAL PROFICIENCY: yes

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: yes
- Acceptance criteria met for positive control: yes

Any other information on results incl. tables

Values Negative Control

Parameter	Negative Control
	1. Rep.	2. Rep.	3. Rep.
Opacity before exposure	2.84	2.75	3.57
Opacity after exposure	5.49	5.88	4.88
Opacity Difference	2.66	3.13	1.31
Mean Opacity Difference	2.36

Rep. = Replicate

Opacity Values Test Item and Positive Control

Parameter	Test Item			Positive Control
	1. Rep.	2. Rep.	3. Rep.	1. Rep.	2. Rep.	3. Rep.
Opacity before exposure	2.54	3.53	1.49	2.01	2.54	1.33
Opacity after exposure	5.16	4.42	4.69	99.76	97.95	96.62
Opacity Difference	2.62	0.89	3.21	97.76	95.41	95.29
Opacity Difference corrected	0.25	-1.47	0.85	95.39	93.04	92.93
Mean Opacity Difference corrected	-0.12			93.79

Rep. = Replicate

Optical density at 492 nm of Negative Control, Test Item and Positive Control

Parameter	Negative Control			Test Item			Positive Control
	1. Rep.	2. Rep.	3. Rep.	1. Rep.	2. Rep.	3. Rep.	1. Rep.	2. Rep.	3. Rep.
1. Measurement	0.050	0.045	0.065	0.048	0.053	0.049	0.950	1.392	1.931
2. Measurement	0.051	0.043	0.056	0.047	0.053	0.043	0.962	1.388	1.998
3. Measurement	0.048	0.043	0.057	0.048	0.052	0.041	0.952	1.394	1.953
1. Measurement – blank	0.0070	0.0020	0.0220	0.0050	0.0100	0.0060	0.9070	1.3490	1.8880
2. Measurement – blank	0.0080	0.0000	0.0130	0.0040	0.0100	0.0000	0.9190	1.3450	1.9550
3. Measurement – blank	0.0050	0.0000	0.0140	0.0050	0.0090	-0.0020	0.9090	1.3510	1.9100
Mean of each replicate	0.0067	0.0007	0.0163	0.0047	0.0097	0.0013	0.9117	1.3483	1.9177
Mean of the 3 replicates	0.0079			--			--
Corrected	--	--	--	-0.0032	0.0018	-0.0066	0.9038	1.3404	1.9098
Corrected mean of the 3 replicates	--			-0.0027			1.3847

IVIS

Test Group	IVIS	Mean IVIS	Relative Standard Deviation IVIS
Negative Control HBSS	2.76	2.48	33.25%
	3.14
	1.55
Test Item 7-(4-ethyl-1-methyloctyl)quinolin-8-ol	0.21	-0.16	697.17%
	-1.44
	0.75
Positive Control DMF undiluted	108.95	114.56	5.61%
	113.15
	121.58

 

Note: the high relative standard deviation of the IVIS of test item is due to mathematical reasons, as the respective means are very small

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test item 7-(4-ethyl-1-methyloctyl)quinolin-8-ol showed no effects on the cornea of the bovine eye. The calculated mean IVIS (In Vitro Irritancy Score) was -0.16.

The experiment is considered as sufficient for the classification of the test item, because all three replicates of the test item lead to the same assessment for the test item.

Executive summary:

Findings and Results:

One valid experiment was performed.

Bovine corneas were used. They were collected from slaughtered cattle that were between 12 and 60 months old. The test item 7-(4-ethyl-1-methyloctyl)quinolin-8-ol was applied onto the cornea of a bovine eye which had been previously incubated with cMEM without phenol red at 32 ± 1 °C for 1 hour and whose opacity had been measured.

The test item was incubated on the cornea for 10 minutes at 32 ± 1 °C. After removal of the test item and 2 hours post-incubation, opacity and permeability values were measured.

Hank’s Balanced Salt Solution (HBSS) was used as negative control. The negative control showed no irritating effect on the cornea and the calculated mean IVIS (In Vitro Irritancy Score) was 2.48.

Dimethylformamide (DMF) undiluted was used as positive control. The positive control induced serious eye damage on the cornea and was within two standard deviations of the current historical mean. The calculated mean IVIS was 114.56.

Under the conditions of this study, the test item 7-(4-ethyl-1-methyloctyl)quinolin-8-ol showed no effects on the cornea of the bovine eye. The calculated mean IVIS was -0.16.

According to OECD Guideline no. 437 (Oct. 2017), a substance with an IVIS ≤ 3 requires no classification for eye irritation or serious eye damage.