Tetrahydro-6-(3-pentenyl)-2H-pyran-2-one

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study performed under GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), 12 Nohsan, Notification No. 8147, April 2011; including the most recent partial revisions.

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Tetrahydro-6-(3-pentenyl)-2H-pyran-2-one

EC Number:

251-201-7

EC Name:

Tetrahydro-6-(3-pentenyl)-2H-pyran-2-one

Cas Number:

32764-98-0

Molecular formula:

C10H16O2

IUPAC Name:

tetrahydro-6-(3-pentenyl)-2H-pyran-2-one

Test material form:

gas under pressure: refrigerated liquefied gas

Details on test material:

- Physical state: liquid
- Storage condition of test material: in refrigerator (2-8°C) in the dark under nitrogen

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Recognised animal supplier
- Age at study initiation: at least 6 weeks old
- Weight at study initiation: at least 1.0kg
- Housing: individually housed in labeled cages with perforated floors (dimensions 67 x 62 x 55 cm) and shelters.
- Diet (e.g. ad libitum): certified pellet diet (100g a day) and wooden sticks
- Water (e.g. ad libitum): tap water ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18 - 24
- Humidity (%): 40 - 70
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12 hour light/12 hour dark

IN-LIFE DATES: From: 04/02/13 To: 18/02/13

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.1 mL
- Concentration (if solution): undiluted

Duration of treatment / exposure:

Each animal was treated by instillation of 0.1 mL of the test substance, in the conjunctival sac of one of the eyes after gently pulling the lower lid away from the eyeball. The lids were then gently held together for about one second to prevent loss of the test substance. The other eye remained untreated and served as the reference control. Immediately after the 24-hour observation, a solution of 2% fluorescein in water (adjusted to pH 7.0) was instilled into both eyes of each animal to quantitatively determine corneal epithelial damage.

Observation period (in vivo):

The eyes of each animal were examined approximately 1, 24, 48 and 72 hours and 7 days after instillation of the test substance.

Number of animals or in vitro replicates:

3 males

Details on study design:

The study was performed in a stepwise manner and was started by treatment of a single rabbit (sentinel). The two other animals were treated in a similar manner 1 week s later, after considering the degree of eye irritation observed in the first animal.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): none

SCORING SYSTEM:
The irritation was assessed according to the following numerical scoring system. At each observation, the highest scores given were recorded:

CORNEAL IRRITATION
Opacity: degree of density (area most dense taken for reading)
No ulceration or opacity (may include slight dulling of normal luster) 0
Scattered or diffuse areas of opacity, details of iris clearly visible 1
Easily discernible translucent area, details of iris slightly obscured 2
Nacreous area, no details of iris visible, size of pupil barely discernible 3
Opaque cornea, iris not discernible through the opacity 4

Area of cornea involved:
No ulceration or opacity 0
One quarter or less but not zero 1
Greater than one quarter, but less than half 2
Greater than half, but less than three quarters 3
Greater than three quarters, up to whole area 4

IRIS
Normal 0
Markedly deepened rugae, congestion, swelling, moderate circumcorneal hyperaemia,
or injection, any of these or combination thereof, iris still reacting to light
(sluggish reaction is positive) 1
No reaction to light, hemorrhage, gross destruction (any or all of these) 2

CONJUNCTIVAL IRRITATION
Redness (refers to palpebrae and sclera, excluding cornea and iris):
Blood vessels normal 0
Some blood vessels definitely hyperaemic (injected) 1
Diffuse, crimson color, individual vessels not easily discernible 2
Diffuse beefy red 3

Chemosis (refers to lids and/or nictitating membranes):
No swelling 0
Any swelling above normal (includes nictitating membranes) 1
Obvious swelling with partial eversion of lids 2
Swelling with lids about half closed 3
Swelling with lids more than half closed 4

Discharge:
No discharge (may include small amounts observed in inner canthus of normal animals) 0
Any amount different from normal and/or lacrimation 1
Discharge with moistening of the lids and hairs just adjacent to lids 2
Discharge with moistening of the lids and hairs (considerable area around the eye) 3

TOOL USED TO ASSESS SCORE: ophthalmic examination lamp

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

other: 24, 48, 72 hours

Score:

0

Max. score:

4

Results 2

Irritation parameter:

iris score

Basis:

mean

Time point:

other: 24, 48, 72 hours

Score:

0

Max. score:

2

Results 3

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

other: 24, 48, 72 hours

Score:

1.13

Max. score:

3

Reversibility:

fully reversible

Results 4

Irritation parameter:

chemosis score

Basis:

mean

Time point:

other: 24, 48, 72 hours

Score:

0.53

Max. score:

4

Reversibility:

fully reversible

Irritant / corrosive response data:

Irritation of the conjunctivae, which consisted of redness, chemosis and discharge was observed in all test animals. The irritation had completely resolved within 48 hours in one animal and within 7 days in the other two animals. No iridial irritation or corneal opacity were observed, and treatment of the eyes with 2% fluorescein 24 hours after test substance instillation revealed no corneal epithelial damage. There was no evidence of ocular corrosion.

Other effects:

No symptoms of systemic toxicity were observed in the animals during the test period and no mortality occurred.

Any other information on results incl. tables

Table 1. Individual scores

Animal	Time after dosing	Cornea			Iris	Conjunctivae
		Opacity	Area	Fluorescein area		Redness	Chemosis	Discharge
1	1h	0	0	-	0	2	2	2
	24h	0	0	0	0	2	2	1
	38h	0	0	-	0	2	1	1
	72h	0	0	-	0	1	0	0
	7d	0	0	-	0	0	0	0
2	1h	0	0	-	0	2	2	2
	24h	0	0	0	0	2	1	1
	38h	0	0	-	0	2	0	0
	72h	0	0	-	0	1	0	0
	7d	0	0	-	0	0	0	0
3	1h	0	0	-	0	2	2	2
	24h	0	0	0	0	1	1	1
	38h	0	0	-	0	1	0	0
	72h	0	0	-	0	0	0	0
	7d	0	0	-	0	0	0	0

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of this study the test material is not irritating to New Zealand white rabbit eyes.

Executive summary:

The study was performed to assess the irritancy potential of the test material to the eye following a single application in the New Zealand White rabbit. The study was performed to GLP and the method was designed to meet the requirements of OECD Guidelines for the Testing of Chemicals No. 405. A volume of 0.1 ml of the test material was placed into the conjunctival sac of one eye of 3 animals. The other eye remained untreated and was used for control purposes. Assessment of ocular damage/irritation was made approximately 1 hour and 24, 48 and 72 hours following treatment. No corneal (opacity) or iridial effects were noted during the study. Minimal to moderate (grade 1 to 2) conjunctival irritation was noted for all animals at the 1 to 48 -hour observations.The irritation had completely resolved by 7 days in all animals. Under the conditions of this study the test material is not considered to be irritating to New Zealand White rabbit eyes.