Tris(2-ethylhexyl) orthoborate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

01 October 2003 to 08 December 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

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

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Details on test material:

- Physical state: Colourless liquid
- Date received: 20 December 2002
- Storage condition of test material: Room temperature in the dark, over silica gel, under nitrogen

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

ANIMALS AND ANIMAL HUSBANDRY
- Three New Zealand White rabbits were supplied by David Percival Ltd, Moston, Sandbach, Cheshire, UK.
- At the start of the study the animals were in the weight range 2.0 kg to 3.5 kg and were 12 to 20 weeks old.
- After an acclimatisation period of at least 5 days each animal was given a number unique within the study, which was written with a black indelible marker-pen on the inner surface of the ear and on the cage label.
- Animals were individually housed in suspended metal cages.
- Free access to mains drinking water and food (Certified Rabbit Diet (Code 5322) supplied by International Product Supplies Limited, Wellingborough, Northants, UK) was allowed throughout the study.
- The diet and drinking water were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.
- Temperature and relative humidity were set to achieve limits of 17 °C to 23 °C and 30 % to 70 % respectively. Any occasional deviations from these targets were considered not to have affected the purpose or integrity of the study.
- The rate of air exchange was at least 15 changes per hour.
- Lighting was controlled by a time switch to give 12 hours continuous light (06:00 to 18:00) and 12 hours darkness.
- Animals were provided with environmental enrichment items, which were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.1 mL

Duration of treatment / exposure:

Single application

Observation period (in vivo):

14 days

Number of animals or in vitro replicates:

Three

Details on study design:

PREPARATION OF TEST MATERIAL
- The absorption of the test material was not determined.

MEASUREMENT OF pH
- The pH of the test item was determined prior to commencement of the study and found to be 4.7 for a 10 % v/v aqueous preparation.

PROCEDURE
- Immediately before the start of the test, both eyes of the provisionally selected test rabbits were examined for evidence of ocular irritation or defect with the aid of a light source from a standard opthalmoscope.
- Only animals free of ocular damage were used.
- Initially, a single rabbit was treated. A volume of 0.1 mL of the test material was placed into the conjunctival sac of the right eye, formed by gently pulling the lower lid away from the eyeball. The upper and lower lids were held together for about 1 s immediately after treatment, to prevent loss of the test material, and then released.
- Immediately after adinistration of the test material, an assessment of the initial pain reaction was made according to the six point scale shown in Appendix 1 (attached).
- After consideration of the ocular responses produced in the first treated animal, two additional animals were treated. In order to minimise pain on application of the test material, one drop of local anaesthetic (amethocaine hydrochloride 0.5 %, Chauvin Pharmaceuticals, Romford, Essex, UK) was instilled into both eyes of these animals 1 to 2 minutes before treatment.
- Assessment of ocular damage was made approximately 1 hour and 24, 48 and 72 hours following treatment according to the numerical evaluation (Draize scale) given in Appendix 2 (attached).
- Any other ocular effects were also noted. Examination of the eye was facilitated by the use of the light source from a standard opthalmoscope.
- Additional observations were made on Days 7 and 14 to assess the reversibility of the ocular effects.

INTERPRETATION OF RESULTS
- Numerical scores corresponding to each animal, tissue and observation time were recorded.
- Data relating to the conjuntivae were designated by the letters A (redness), B (chemosis) and C (discharge).
- Data relating to the iris were designated by the letter D.
- Data relating to the cornea were designated by the letter E (degree of opacity) and F (area of cornea involved).
- Score for conjuntivae = (A + B + C) * 2
- Score for iris = D * 5
- Score for cornea = (E x F) * 5
- Using the numerical data obtained, a modified version of the system described by Kay and Calandra (1962) was used to classify the ocular irritancy potential of the test material (see Appendix 3, attached). This was achieved by adding together the scores for the cornea, iris and conjuntivae for each time point for each rabbit.
- The group means of the total scores for each observation were calculated. The highest of these group means (the maximum group mean score) together with the persistence of the reactions enabled classification of the eye irritancy potential of the test material.
- If evidence of irreversible ocular damage was noted, the test material would be classified as corrosive to the eye.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Remarks:

opacity

Basis:

animal #1

Remarks:

mean score

Time point:

other: 24, 48 and 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Remarks on result:

other: 178 male

Results 2

Irritation parameter:

iris score

Basis:

animal #1

Remarks:

mean score

Time point:

other: 24, 48 and 72 h

Score:

0.33

Max. score:

2

Reversibility:

fully reversible within: 48 h

Remarks on result:

other: 178 male

Results 3

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #1

Remarks:

mean score

Time point:

other: 24, 48 and 72 h

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 72 h

Remarks on result:

other: 178 male

Results 4

Irritation parameter:

chemosis score

Basis:

animal #1

Remarks:

mean score

Time point:

other: 24, 48 and 72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 72 h

Remarks on result:

other: 178 male

Results 5

Irritation parameter:

cornea opacity score

Remarks:

opacity

Basis:

animal #2

Remarks:

mean score

Time point:

other: 24, 48 and 72 h

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 7 d

Remarks on result:

other: 14 male

Results 6

Irritation parameter:

iris score

Basis:

animal #2

Remarks:

mean score

Time point:

other: 24, 48 and 72 h

Score:

0.67

Max. score:

2

Reversibility:

fully reversible within: 7 d

Remarks on result:

other: 14 male

Results 7

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #2

Remarks:

mean score

Time point:

other: 24, 48 and 72 h

Score:

2

Max. score:

3

Reversibility:

fully reversible within: 14 d

Remarks on result:

other: 14 male

Results 8

Irritation parameter:

chemosis score

Basis:

animal #2

Remarks:

mean score

Time point:

other: 24, 48 and 72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 14 d

Remarks on result:

other: 14 male

Results 9

Irritation parameter:

cornea opacity score

Remarks:

opacity

Basis:

animal #3

Remarks:

mean score

Time point:

other: 24, 48 and 72 h

Score:

1.67

Max. score:

4

Reversibility:

fully reversible within: 7 d

Remarks on result:

other: 15 male

Results 10

Irritation parameter:

iris score

Basis:

animal #3

Remarks:

mean score

Time point:

other: 24, 48 and 72 h

Score:

1

Max. score:

2

Reversibility:

fully reversible within: 7 d

Remarks on result:

other: 15 male

Results 11

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #3

Remarks:

mean score

Time point:

other: 24, 48 and 72 h

Score:

2

Max. score:

3

Reversibility:

fully reversible within: 14 d

Remarks on result:

other: 15 male

Results 12

Irritation parameter:

chemosis score

Basis:

animal #3

Remarks:

mean score

Time point:

other: 24, 48 and 72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 14 d

Remarks on result:

other: 15 male

Any other information on results incl. tables

RESULTS

- Individual and group mean scores for ocular irritiation are given in Table 1 and Table 2 (attached).

- Scattered or diffuse corneal opacity was noted in one treated eye at the 24 hour observation with translucent corneal opacity at the 48 hour and 72 hour observation. Scattered or diffuse corneal opacity was alo noted in one other treated eye at the 48 hour and 72 hour observation.

- Iridial inflammation was noted in two treated eyes at the 24 hour observation. Iridial inflammation persisted in one treated eye, developed in one other treated eye at the 48 hour observation and persisted in these two treated eyes at the 72 hour observation.

- Moderate conjunctival irritation was noted in all treated eyes at 1 hour and 24 hours after treatment. Moderate conjunctival irritation was noted in two treated eyes with minimal conjunctival irritation noted in the remaining treated eye at the 48 hour observation. Moderate conjunctival irritation was noted in two treated eyes at the 72 hour observation with minimal conjunctival irritation at the 7 day observation.

- Pale appearance of the nictitating membrane was noted in one treated eye at the 48 hour and 72 hour observations.

- One treated eye appeared normal at the 72 hour observation and the remaining treated eyes appeared normal at the 14 day observation.

Applicant's summary and conclusion

Interpretation of results:

other: Irritating to eyes (category 2)

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

The test material produced a maximum group mean score of 24.3 and was classified as a moderate irritant (Class 5 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system. Since the mean scores for conjunctival redness and chemosis calculated from observations at 24, 48 and 72 hours were ≥ 2 in two out of three animals, classification as irritating to eyes (category 2) is required in accordance with Regulation (EC) No 1272/2008..

Executive summary:

INTRODUCTION

The study was performed to assess the irritancy potential of the test material to the eye of the New Zealand White rabbit. The method was designed to meet the requirements of OECD Guidelines for the Testing of Chemicals No 405 "Acute Eye Irritation/Corrosion" (adopted 24 April 2002) and Commission Directive 92/69/EEC Method B.5 Acute Toxicity (Eye Irritation).

RESULT

A single application of the test material to the non-irrigated eye of three rabbits produced scattered or diffuse to translucent corneal opacity, iridial inflammation and moderate conjunctival irritation. Pale appearance of the nictitating membrane was also noted in one treated eye. One treated eye appeared normal at the 72 hour observation and the remaining treated eyes appeared normal at the 14 day observation.

CONCLUSION

The test material produced a maximum group mean score of 24.3 and was classified as a moderate irritant (Class 5 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system. Since the mean scores for conjunctival redness and chemosis calculated from observations at 24, 48 and 72 hours were ≥ 2 in two out of three animals, classification as irritating to eyes (category 2) is required in accordance with Regulation (EC) No 1272/2008.