Chlorocresol

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Chlorocresol

EC Number:

200-431-6

EC Name:

Chlorocresol

Cas Number:

59-50-7

Molecular formula:

C7H7ClO

IUPAC Name:

4-chloro-3-methylphenol

Test material form:

solid: crystalline

Details on test material:

- Name of test material (as cited in study report): chlorocresol
- Substance type: Organic
- Physical state: solid

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Institute for Industrial Research & Toxicology
- Sex: Female
- Age at study initiation: 10 to 12 weeks
- Weight at study initiation: 2.0kg ±200g
- Housing: Rabbit was housed in stainless steel cages provided with stainless steel mesh bottom and facilities for food and water bottle
- Diet (e.g. ad libitum): Pelleted feed supplied by Pranav agro Industries Ltd., B7/6 Ramesh Nagar, Delhi, India
- Water (e.g. ad libitum): Community tap water passed through ‘Aqua Guard on line water filter’ was kept in bottles, ad libitum
- Acclimation period: 24 hours

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22-25°C
- Humidity (%): 40-60%
- Air changes (per hr): 10-15 air changes per hour
- Photoperiod (hrs dark / hrs light): illumination cycle set to 12 hours artificial fluorescent light and 12 hours dark

Test system

Vehicle:

water

Controls:

yes

Amount / concentration applied:

0.1 gm moistened with distilled water

Duration of treatment / exposure:

24 hours

Observation period (in vivo):

upto 21 days after exposure

Number of animals or in vitro replicates:

3

Details on study design:

PREPARATION AND TREATMENT OF ANIMALS
Selection of species:
The albino rabbit is the preferable laboratory animal and only healthy young adult animals are used.
Preparation of animals:
Both eyes of each experimental animal provisionally selected and examined for any eye irritation, ocular defects and pre-existing corneal injury within 24 hours before testing of compound.
TEST PROCEDURE:
The test compound Chlorocresol (CAS No.-59-50-7) in the amount of 0.1 gm moistened with distilled water and then placed in the conjunctival sac of one eye of each animal after gentle pulling the lower eye lid away from the eye ball. The eye lids were then gently held together for about one second to prevent the loss of the material. The other eyes which remains untreated, served as control.
Eye Irrigation:
The eyes of the test animal did not washed for at least 24 hours following instillation of the test compound. At 24 hours a washout may be used if considered appropriate.
Dose level:
A dose of 0.1gm of test substance was applied into the one eye of the rabbits. The other eye, which remains untreated, serves as a control.
OBSERVATION:
The eyes were examined at 1, 24, 48 and 72 hours after test substance application. The grades of ocular reaction (conjunctiva, cornea and iris) were recorded at each observation. To determine the reversibility of the effect the animal was observed normally for 21 days. Any other lesions in the eye viz pannus, staining were observed and scored accordingly. Examination of reactions was facilitated by use of biomicroscope and hand slit lamp. After recording the observations at 24 hours, the eyes were further examined with the aid of fluorescein. Individual animal weight before and during the study was also observed

Results and discussion

In vivo

Results

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: 72 hours

Score:

58

Max. score:

110

Reversibility:

fully reversible

Remarks on result:

other: Severely irritating

Irritant / corrosive response data:

Irritation Scoring
The test compound Chlorocresol (CAS No.: 59-50-7) when applied to the eye of New Zealand white rabbit at the dose level of 0.1 gm showed cornea discernible translucent area, details of iris slightly obscured, iris showed sluggish reaction to light, conjunctiva observed crimson red colour, half closed of eye lid and eye discharge moistening eye lids and hairs just adjacent to the lids.
Clinical Signs
The test compound Chlorocresol (CAS No.: 59-50-7) applied in conjunctival sac of rabbits did not show any observable clinical signs throughout the observation period of 21 days.

Any other information on results incl. tables

GRADING OF OCULAR LESIONS

 

S.No/ Sex		OBSERVATION	Score				Total	Total Score
1/F			1 hr	24hrs	48 hrs	72 hrs
	Cornea	A.       Opacity-Degree of Density	1	2	2	2	7	7×12×5=420
		B.       Area of Cornea Involved	3	3	3	3	12
	Iris	A.       Values	1	1	2	2	6	6×5=30
	Conjunctivae	A.       Redness	3	3	3	3	12	12+12+11×5=175
		B.       Chemosis	3	3	3	3	12
		C.       Discharge	2	3	3	3	11
		Total						625
		Mean						156.3

At 72 hours,

Cornea score: 3x2x5= 30

Iris Score: 2x5= 10

Conjunctivae score: (3 +3 +3)x2 = 18

Total Score: 30 +10 +18= 58

Applicant's summary and conclusion

Interpretation of results:

Category 1 (irreversible effects on the eye)

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test compound Chlorocresol when applied to the eye of New Zealand white rabbit at the dose level of 0.1 gm showed cornea discernible translucent area, details of iris slightly obscured, iris showed sluggish reaction to light, conjunctiva observed crimson red colour, half closed of eye lid and eye discharge moistening eye lids and hairs just adjacent to the lids.

Executive summary:

The test compound Chlorocresol when applied to the eye of New Zealand white rabbit at the dose level of 0.1 gm showed cornea discernible translucent area, details of iris slightly obscured, iris showed sluggish reaction to light, conjunctiva observed crimson red colour, half closed of eye lid and eye discharge moistening eye lids and hairs just adjacent to the lids.

Based on the result obtained from present study, it can be concluded that the test compound Chlorocresol is maximally irritant to the eyes of New Zealand white rabbit under test condition.