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Toxicological information

Eye irritation

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Administrative data

Endpoint:
eye irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
27 April 2015 to 08 May 2015
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2015
Report Date:
2015

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)
Deviations:
no
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Details on test material:
- Physical state/appearance: Yellow Liquid
- Storage conditions: Room temperature in the dark

Test animals / tissue source

Species:
rabbit
Strain:
New Zealand White
Remarks:
Hsdlf:NZW
Details on test animals or tissues and environmental conditions:
ANIMAL INFORMATION
- Two New Zealand White (Hsdlf:NZW) strain rabbits were supplied by Harlan Laboratories UK Ltd, Leicestershire, UK.
- At the start of the study the animals weighed 2.09 or 2.85 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 black indelible marker pen on the inner surface of the ear and on the cage label.

ANIMAL CARE AND HUSBANDRY
- Animals were individually housed in suspended cages.
- Free access to mains drinking water and food (2930C Teklad Global Rabbit diet supplied by Envigo RMS (UK) Limited, Oxon, UK) was allowed throughout the study.
- Diet and drinking water were not considered 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 to 23 °C and 30 to 70 % respectively.
- 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 that were not considered 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:
not required
Amount / concentration applied:
0.1 mL
Duration of treatment / exposure:
Single application
Observation period (in vivo):
72 hours
Details on study design:
MEASUREMENT OF pH
- The pH of the test item was determined prior to commencement of the study and the findings are shown in the table below.

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 subcutaneous injection of buprenorphine 0.01 mg/kg was administered 60 minutes prior to the test item application to provide a therapeutic level of systemic analgesia.
- Five minutes prior to test item application, a pre-dose anaesthesia of ocular anaesthetic (two drops of 0.5% tetracaine hydrochloride) was applied to each eye.
- Test item (0.1 mL) was placed into the conjunctiva! sac of the right eye, formed by gently pulling the lower lid away from the eyeball. The upper and lower eyelids were held together for about one second immediately after treatment, to prevent loss of the test item, and then released.
- The left eye remained untreated and was used for control purposes.
- Immediately after administration of the test item, an assessment of the initial pain reaction was made according to the six-point scale shown in Appendix 1 (attached).
- Eight hours after test item application, a subcutaneous injection of post-dose analgesia, buprenorphine 0.01 mg/kg and meloxicam 0.5 mg/kg, was administered to provide a continued therapeutic level of systemic analgesia. The treated animal was checked for signs of pain and suffering approximately 12 hours later. No further analgesia was required.
- After consideration of the ocular responses produced in the first treated animal, a second animal was similarly treated.
- Assessment of ocular damage/irritation was made approximately 1 hour and 24, 48 and 72 hours following treatment, according to the numerical evaluation of Draize (1977) 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 ophthalmoscope. Any clinical signs of toxicity, if present, were also recorded.
- Individual body weights were recorded on Day 0 (the day of dosing) and at the end of the observation period.

INTERPRETATION OF RESULTS
- The numerical values corresponding to each animal, tissue and observation time were recorded.
The data relating to the conjunctivae were designated by the letters A (redness), B (chemosis)
and C (discharge), those relating to the iris designated by the letter D and those relating to the
cornea by the letters E (degree of opacity) and F (area of cornea involved).
For each tissue the score was calculated as follows: Score for conjunctivae = (A+ B + C) x 2; score for iris = D x 5; Score for cornea = (E x F) x 5.
- Using the numerical data obtained, a modified version of the system described by Kay J.H. and
Calandra J.C. (1962) (see Appendix 3, attached) was employed to determine the ocular irritancy potential of the test item. This was achieved by adding together the scores for the cornea, iris and conjunctivae 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 determination of the eye irritancy potential of the test item.
- If evidence of irreversible ocular damage is noted, the test item will be considered to be corrosive to the eye.

Results and discussion

In vivo

Resultsopen allclose all
Irritation parameter:
cornea opacity score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0
Max. score:
4
Reversibility:
other: not applicable
Remarks on result:
other: 75050 male
Irritation parameter:
cornea opacity score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0
Max. score:
4
Reversibility:
other: not applicable
Remarks on result:
other: 75060 male
Irritation parameter:
iris score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0
Max. score:
2
Reversibility:
other: not applicable
Remarks on result:
other: 75050 male
Irritation parameter:
iris score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0
Max. score:
2
Reversibility:
other: not applicable
Remarks on result:
other: 45060 male
Irritation parameter:
conjunctivae score
Remarks:
redness
Basis:
animal #1
Time point:
24/48/72 h
Score:
0.67
Max. score:
3
Reversibility:
fully reversible within: 72 h
Remarks on result:
other: 75050 male
Irritation parameter:
conjunctivae score
Remarks:
redness
Basis:
animal #2
Time point:
24/48/72 h
Score:
0.67
Max. score:
3
Reversibility:
fully reversible within: 72 h
Remarks on result:
other: 75060 male
Irritation parameter:
chemosis score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0.33
Max. score:
4
Reversibility:
fully reversible within: 48 h
Remarks on result:
other: 75050 male
Irritation parameter:
chemosis score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0.33
Max. score:
4
Reversibility:
fully reversible within: 48 h
Remarks on result:
other: 45060 male
Irritant / corrosive response data:
OCULAR REACTIONS
- Individual and group mean scores for ocular irritation are given in Table 1 and Table 2 (attached).
- No corneal or iridial effects were noted during the study.
- Moderate conjunctiva! irritation was noted in both treated eyes 1 hour after treatment with minimal conjunctiva! irritation noted at the 24 and 48-hour observations.
- Both treated eyes appeared normal at the 72-hour observation.
Other effects:
BODY WEIGHT
- Individual body weights and body weight change are given in Table 3 (attached).
- Both animals showed expected gain in body weight during the study.

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
The test item produced a maximum group mean score of 8.0 and was considered to be a mild irritant (Class 4 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system
Executive summary:

GUIDELINE

The study was performed to assess the irritancy potential of the test item to the eye of the New Zealand White rabbit in compliance with the OECD Guideline for the Testing of Chemicals No 405 “Acute Eye Irritation/Corrosion” (adopted 02 October 2012) and Method B.5 Acute Toxicity (Eye Irritation) of Commission Regulation (EC) No 440/2008.

 

METHODS

The test involved a single application of the test item to the non-irrigated eye of two rabbits. Initially, a single rabbit was treated. A subcutaneous injection of buprenorphine 0.01 mg/kg was administered 60 minutes prior to test item application to provide a therapeutic level of systemic analgesia. Five minutes prior to test item application, a pre-dose anaesthesia of ocular anaesthetic (two drops of 0.5% tetracaine hydrochloride) was applied to each eye. A volume of 0.1 mL of the test item was placed into the conjunctiva! sac of the right eye, formed by gently pulling the lower lid away from the eyeball. The upper and lower eyelids were held together for about one second immediately after treatment, to prevent loss of the test item, and then released. The left eye remained untreated and was used for control purposes. Immediately after administration of the test item, an assessment of the initial pain reaction was made according to a six-point scale. Eight hours after test item application, a subcutaneous injection of post-dose analgesia, buprenorphine 0.01 mg/kg and meloxicam 0.5 mg/kg, was administered to provide a continued therapeutic level of systemic analgesia. The treated animal was checked for signs of pain and suffering approximately 12 hours later. No further analgesia was required.

After consideration of the ocular responses produced in the first treated animal, a second animal was similarly treated. Assessment of ocular damage/irritation was made approximately 1 hour and 24, 48 and 72 hours following treatment, according to the numerical evaluation of Draize (1977). Any other ocular effects were also noted. Examination of the eye was facilitated by the use of the light source from a standard ophthalmoscope. Any clinical signs of toxicity, if present, were also recorded. Individual body weights were recorded on Day 0 (the day of dosing) and at the end of the observation period.

 

RESULTS

A single application of the test item to the non-irrigated eye of two rabbits produced iridial inflammation and moderate conjunctival irritation. Both treated eyes appeared normal at the 72-hour observation.

 

CONCLUSION

The test item produced a maximum group mean score of 8.0 and was considered to be a mild irritant (Class 4 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system.