Prometryn

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

19 Aug 2004 to 22 Aug 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

Version / remarks:

1998

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: JMAFF 59 NohSan No. 4200

Version / remarks:

January 28, 1985

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Prometryn

EC Number:

230-711-3

EC Name:

Prometryn

Cas Number:

7287-19-6

Molecular formula:

C10H19N5S

IUPAC Name:

6-(methylsulfanyl)-N2,N4-di(propan-2-yl)-1,3,5-triazine-2,4-diamine

Test material form:

solid: particulate/powder

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Remarks:

albino

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Age at study initiation: 12 weeks
- Housing: The animals were singly housed in suspended stainless steel caging with mesh floors which conform to the size recommendations in the most recent Guide for the Care and Use of Laboratory Animals DHEW (NIH). Litter paper was placed beneath the cage and was changed at least three times per week.
- Diet: Pelleted Rabbit Chow
- Water: Filtered tap water was supplied ad-libitum by automatic water dispensing system.
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17-22
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 19 Aug 2004 To: 22 Aug 2004

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

TEST MATERIAL
- One-tenth of a millilitre (0.03 grams)

Duration of treatment / exposure:

single treatment

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

3 males

Details on study design:

PREPARATION AND SELECTION OF ANIMALS
Prior to instillation, both eyes of a number of animals were examined using a fluorescein dye procedure. One drop of 2% ophthalmic fluorescein sodium was instilled into both eyes of each rabbit. The eyes were rinsed with physiological saline (0.9% NaCl) approximately 30 seconds after instillation of the fluorescein. Using an ultraviolet light source, the eyes were checked for gross abnormalities. Three healthy animals without pre-existing ocular irritation were selected for test.

INSTILLATION
Prior to use, the test substance was ground with a mortar and pestle. One-tenth of a milliliter (0.03 grams) of the test substance was instilled into the conjunctival sac of the right eye of each rabbit by pulling the lower lid away from the eyeball. The upper and lower lids were then gently held together for about one second before releasing to minimize loss of the test substance. The other eye of each rabbit remained untreated with the test substance and served as a control. The rabbits were then returned to their designated cages.

OCULAR SCORING
Ocular irritation was evaluated using a high-intensity white light in accordance with Draize et al. (see Table 1 at ‘Any other information on methods and materials incl. tables’) at 1, 24, 48, and 72 hours post-instillation. The fluorescein dye evaluation procedure described above was used at 24 hours to verify the absence of corneal damage. In addition to observations of the cornea, iris and conjunctivae, any other observed lesions were noted. The average score for all rabbits at each scoring period was calculated to aid in data interpretation.

CAGE SIDE OBERVATIONS
The animals were observed for signs of gross toxicity and behavioural changes at least once daily during the test period. Observations included gross evaluation of skin and fur, eyes and mucous membranes, respiratory, circulatory, autonomic and central nervous systems, somatomotor activity and behaviour pattern. Particular attention was directed to observation of tremors, convulsions, salivation, diarrhoea and coma.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

animal: #1, #2, #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Results 2

Irritation parameter:

iris score

Basis:

animal: #1, #2, #3

Time point:

24/48/72 h

Score:

0

Max. score:

2

Remarks on result:

no indication of irritation

Results 3

Irritation parameter:

conjunctivae score

Basis:

animal: #1, #2, #3

Time point:

24/48/72 h

Score:

0.33

Max. score:

3

Reversibility:

fully reversible within: 48 hours

Results 4

Irritation parameter:

chemosis score

Basis:

animal: #1, #2, #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

Within the first hour following test substance instillation, “positive” conjunctivitis was observed in all three treated eyes. The overall incidence and severity of irritation decreased with time. All animals were free of ocular irritation within 48 hours.

Other effects:

All animals appeared active and healthy. There were no signs of gross toxicity, adverse pharmacologic effects or abnormal behaviour.

Any other information on results incl. tables

Table 1. Individual eye irritation scores

	Rabbit #1				Rabbit #2				Rabbit #3
	Hours				Hours				Hours
	1	24	48	72	1	24	48	72	1	24	48	72
I. Cornea
A. Opacity	0	0*	0	0	0	0*	0	0	0	0*	0	0
B. Area	4	4	4	4	4	4	4	4	4	4	4	4
(AxB)x5	0	0	0	0	0	0	0	0	0	0	0	0
II. Iris
A. Values	0	0	0	0	0	0	0	0	0	0	0	0
Ax5	0	0	0	0	0	0	0	0	0	0	0	0
III. Conjunctivae
A. Redness	2	1	0	0	2	1	0	0	2	1	0	0
B. Chemosis	0	0	0	0	0	0	0	0	0	0	0	0
C. Discharge	1	0	0	0	0	0	0	0	1	0	0	0
(A+B+C)x2	6	2	0	0	4	2	0	0	6	2	0	0
Total	6	2	0	0	4	2	0	0	6	2	0	0

* 2% ophthalmic fluorescein sodium used to verify the absence of corneal opacity.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of the study (OECD 405, GLP), the mean irritation scores for the 24/48/72 hour time points were determined to be 0 for all animals for corneal opacity, iritis and chemosis. The mean irritation scores for the 24/48/72 hour time points for conjunctival redness was determined to be 0.33 for all animals.

Executive summary:

A primary eye irritation test was conducted with rabbits, in accordance with GLP and OECD guideline 405, to determine the irritation potential of the substance after a single instillation into the eye. An aliquot of 0.1 mL (0.03 grams) test substance was instilled into the right eye of three healthy rabbits. The left eye remained untreated and served as a control. Ocular irritation was evaluated by the method of Draize et al.

Within the first hour following test substance instillation, “positive” conjunctivitis was observed in all three treated eyes. The overall incidence and severity of irritation decreased with time. All animals were free from ocular irritation within 48 hours. The mean irritation scores for the time points after 24/48/72 hours were determined to be 0 for all animals for corneal opacity, iritis and chemosis. The mean irritation scores for the time points after 24/48/72 hours for conjunctival redness were determined to be 0.33 for all animals.

Under the conditions of this study, the test substance was considered to be not irritating to the eyes of rabbits.