2-(3-Chloro-2-pyridinyl)-5-oxo-3-pyrazolidinecarboxylic acid ethyl ester

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

June 2006 - October 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

Version / remarks:

1998

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1992

Test guideline 3

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

2002

GLP compliance:

yes

Remarks:

The in-life portion of the study was conducted without a signed protocol and was not inspected by Quality Assurance. A Short-Term Study Protocol Sheet (STSPS) and a testing SOP was followed. These deviations did not affect the validity of the study.

Test material

Test material information

Constituent 1

Reference substance name:

ethyl 2-(3-chloropyridin-2-yl)-5-oxopyrazolidine-3-carboxylate

EC Number:

610-490-3

Cas Number:

500011-88-1

Molecular formula:

C11H12ClN3O3

IUPAC Name:

ethyl 2-(3-chloropyridin-2-yl)-5-oxopyrazolidine-3-carboxylate

Test material form:

solid

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Covance Research Products, Denver, Pennsylvania.
- Age at study initiation: Young adults
- Weight at study initiation: 3405 - 4091 g
- Housing: All animals were housed singly in stainless steel, wire-mesh cages suspended above cage boards
- Diet: Approximately 125 grams of PMI® Nutrition International, LLC Certified Rabbit LabDiet® 5322 daily
- Water: Ad libitum
- Acclimation period: At least 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 16-22°C
- Humidity (%): 30-70%
- Air changes (per hr): Not recorded
- Photoperiod (hrs dark / hrs light):12-hour light/dark cycle.

IN-LIFE DATES: From June 26, 2006 to August 7, 2006

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

TEST MATERIAL
- Amount applied: Approximately 80 mg

Duration of treatment / exposure:

Single exposure

Observation period (in vivo):

1, 24, 48, and 72 hours and up to 7 days after dosing

Number of animals or in vitro replicates:

3 male rabbits

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): The eyes remained unwashed following treatment.

SCORING SYSTEM: According to Draize Scale for Scoring Ocular Lesions

TOOL USED TO ASSESS SCORE: fluorescein
At each of these observation periods, eyes were examined using illumination and magnification and scored for ocular reactions according to the Draize Scale. Any other adverse ocular reactions, particularly those indicative of corrosive action, were also noted. Control eyes were not scored. These untreated eyes were used for comparison and were considered "normal" relative to the treated eye. Fluorescein stain examinations were conducted at the 24-hour and each subsequent evaluation.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Results 2

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Results 3

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

2

Reversibility:

fully reversible within: 7 days

Results 4

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Results 5

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Results 6

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

1

Reversibility:

fully reversible within: 7 days

Results 7

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Results 8

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Results 9

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

3

Max. score:

3

Reversibility:

fully reversible within: 7 days

Results 10

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Results 11

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Results 12

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

3

Reversibility:

fully reversible within: 7 days

Irritant / corrosive response data:

A skin irritation study was previously conducted. The test substance was not a severe skin irritant or corrosive to the skin.

Any other information on results incl. tables

Table 1: Individual Rabbit Ocular Irritation Scores Following Treatment

 

Reading	Rabbit number	Cornea		Iritis	Conjunctiva			Fluorescein stain
		Opacity	Area		Redness	Chemosis	Discharge
1 hour	201	0	0	0	1	0	0	NA
	216	0	0	0	1	0	0	NA
	223	0	0	0	2	1	0	NA
24 hours	201	0	0	0	0	0	0	NEG
	216	0	0	0	0	0	0	NEG
	223	2	1	1	2	3	0	POS
48 hours	201	0	0	0	0	0	0	NEG
	216	0	0	0	0	0	0	NEG
	223	2	1	0	3	2	1	POS
72 hours	201	0	0	0	0	0	0	NEG
	216	0	0	0	0	0	0	NEG
	223	1	1	0	3	1	0	NEG
7 days	201	-	-	-	-	-	-	-
	216	-	-	-	-	-	-	-
	223	0	0	0	0	0	0	NEG

POS= positive for corneal injury
NEG= negative for corneal injury
NA = not applicable
-- = Not evaluated since all ocular irritation cleared prior to this timepoint
Rabbit no. 201: Initial rabbit tested.

 

Table 2: Mean scores for ocular responses for individual rabbits

 

Rabbit number	Corneal opacity	Iritis	Conjunctival redness	Conjunctival chemosis
201	0	0	0	0
216	0	0	0	0
223	1,67	0,33	2,67	2

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of the present study, classification for eye irritation is not required.

Executive summary:

The objective of this study was to evaluate the eye irritation potential and the reversibility of ocular effects of the test item following a single ocular application to albino rabbits according to OECD Guideline 405.

The test substance was evaluated for acute eye irritation potential in 3 young adult New Zealand White rabbits. Approximately 80 mg of test substance was administered to 1 eye of each animal. The eyes remained unwashed following treatment. One rabbit was initially treated. Since no severe irritation or corrosion was observed, 2 additional rabbits were treated to complete the test. The conjunctiva, iris, and cornea of each treated eye were evaluated and scored according to a numerical scale approximately 1, 24, 48, and 72 hours following administration of the test substance. One rabbit was further examined 7 days after instillation.

The test substance produced corneal opacity (score of 1 or 2), iritis (score of 1), conjunctival redness (score of 2 or 3), conjunctival chemosis (score of 1, 2, or 3), and discharge (score of 1) in the treated eye of one rabbit. Fluorescein stain examinations were positive for corneal injury in the treated eye of this rabbit at 24 and 48 hours. The treated eye of this rabbit was normal by 7 days after instillation of the test substance. Conjunctival redness (score of 1) was observed at one hour in the treated eyes of the remaining two rabbits. The fact that one animal had more severe effects than the other two rabbits is attributed to animal variability. The rabbits exhibited no clinical signs or body weight loss during the study. Mean values were calculated for each animal separately by using numerical scores obtained from the quantitative evaluation of each ocular response observed in each rabbit approximately 24, 48, and 72 hours following treatment. These values are as follows:

 

Rabbit number	Corneal opacity	Iritis	Conjunctival redness	Conjunctival chemosis
201	0	0	0	0
216	0	0	0	0
223	1,67	0,33	2,67	2

Based on the result of this study, classification is not required.