1,1,3,3-tetramethylbutyl 2-ethylperoxyhexanoate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

09 January 2012 and 19 January 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study is performed according to OECD guidelines and GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

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

Reference substance name:

1,1,3,3-tetramethylbutyl 2-ethylperoxyhexanoate

EC Number:

244-894-2

EC Name:

1,1,3,3-tetramethylbutyl 2-ethylperoxyhexanoate

Cas Number:

22288-43-3

Molecular formula:

C16H32O3

IUPAC Name:

2,4,4-trimethylpentan-2-yl 2-ethylhexaneperoxoate

Test material form:

other: liquid

Details on test material:

Sponsor's identification: 1,1,3,3-tetramethylbutyl 2-ethylperoxyhexanoate (CAS 22288-43-3)
Description : clear colourless liquid
Batch number : 1009442440
Purity : 90.8%
Date received : 08 November 2011
Expiry date : 01 October 2012
Storage conditions: approximately -20°C in the dark
The integrity of supplied data relating to the identity, purity and stability of the test item is the responsibility of the Sponsor.
A Certificate of Analysis supplied by the Sponsor is given in Appendix 4 (attachment 1).

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

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 2.11 or 2.82 kg and were twelve to twenty weeks old. After an acclimatisation period of at least five 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.
The animals were individually housed in suspended cages. Free access to mains drinking water and food (2930 Teklad Global Certified Rabbit diet supplied by Harlan Laboratories UK Ltd., Oxon, 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.
The temperature and relative humidity were set to achieve limits of 17 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 fifteen changes per hour and the lighting was controlled by a time switch to give twelve hours continuous light (06:00 to 18:00) and twelve hours darkness.
The 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:

other: The left eye remained untreated and was used for control purposes.

Amount / concentration applied:

A volume of 0.1 ml of the test item was placed into the conjunctival sac of the right eye

Duration of treatment / exposure:

1 hour

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

2

Details on study design:

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 ophthalmoscope. Only animals free of ocular damage were used.
Initially, a single rabbit was treated. A volume of 0.1 ml of the test item 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 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.
After consideration of the ocular responses produced in the first treated animal, a second animal was treated.
Assessment of ocular damage/irritation was made approximately 1 hour and 24, 48 and 72 hours following treatment, according to the numerical evaluation given in Appendix 2, (from Draize J H (1977) "Dermal and Eye Toxicity Tests" In: Principles and Procedures for Evaluating the Toxicity of Household Substances, National Academy of Sciences, Washington DC p.48 to 49).
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 bodyweights were recorded on Day 0 (the day of dosing) and at the end of the observation period.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

animal: 71538 Male

Time point:

other: Score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: No effects observed

Results 2

Irritation parameter:

cornea opacity score

Basis:

animal: 71584 Male

Time point:

other: Score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: No effects observed

Results 3

Irritation parameter:

iris score

Basis:

animal: 71538 Male

Time point:

other: Score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

2

Reversibility:

other: No effects observed

Results 4

Irritation parameter:

iris score

Basis:

animal: 71584 Male

Time point:

other: Score at 1, 24, 48 and 72 hours

Score:

0

Max. score:

2

Reversibility:

other: No effects observed

Results 5

Irritation parameter:

other: redness

Basis:

animal: 71538 Male

Time point:

other: Score at 1, 24, 48 and 72 hours

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 48 hours

Results 6

Irritation parameter:

other: redness

Basis:

animal: 71584 Male

Time point:

other: Score at 1, 24, 48 and 72 hours

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 48 hours

Results 7

Irritation parameter:

chemosis score

Basis:

animal: 71538 Male

Time point:

other: Score at 1, 24, 48 and 72 hours

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 24 hours

Results 8

Irritation parameter:

chemosis score

Basis:

animal: 71584 Male

Time point:

other: Score at 1, 24, 48 and 72 hours

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 48 hours

Irritant / corrosive response data:

Individual and group mean scores for ocular irritation are given in Table 1 and Table 2.
No corneal or iridial effects were noted during the study.
Minimal conjunctival irritation was noted in both treated eyes one and 24 hours after treatment.
Both treated eyes appeared normal at the 48-Hour observation.

Other effects:

Individual bodyweights and bodyweight changes are given in Table 3.
Both animals showed expected gain in bodyweight during the study.

Any other information on results incl. tables

Interpetation 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), J. Soc. Cosmet. Chem.13, 281‑289 (see Appendix 3) was used to classify 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 classification of the eye irritancy potential of the test item.

If evidence of irreversible ocular damage is noted, the test item will be classified as corrosive to the eye.

The results were also interpreted according to Regulation (EC) No. 1272/2008 on the classification, labelling and packaging of substances and mixtures.

Table 1              Individual Scores and Individual Total Scores for Ocular Irritation

Rabbit Number and Sex	71538Male				71584Male
	IPR= 1				IPR = 1
Time After Treatment	1 Hour	24 Hours	48 Hours	72 Hours	1 Hour	24 Hours	48 Hours	72 Hours
CORNEA
E = Degree of Opacity	0	0	0	0	0	0	0	0
F = Area of Cornea Involved	0	0	0	0	0	0	0	0
Score (E x F) x 5	0	0	0	0	0	0	0	0
IRIS
D	0	0	0	0	0	0	0	0
Score (D x 5)	0	0	0	0	0	0	0	0
CONJUNCTIVAE
A = Redness	1	1	0	0	1	1	0	0
B = Chemosis	1	0	0	0	1	0	0	0
C = Discharge	0	0	0	0	0	0	0	0
Score (A + B + C) x 2	4	2	0	0	4	2	0	0
Total Score	4	2	0	0	4	2	0	0

IPR=  Initial pain reaction

Table 2              Individual Total Scores and Group Mean Scores for Ocular Irritation

Rabbit Number and Sex	Individual Total Scores At:
	1 Hour	24 Hours	48 Hours	72 Hours
71538Male	4	2	0	0
71584Male	4	2	0	0
Group Total	8	4	0	0
Group Mean Score	4.0	2.0	0.0	0.0

Table 3              Individual Bodyweights and Bodyweight Changes

Rabbit Number and Sex	Individual Bodyweight (kg)		Bodyweight Change (kg)
	Day 0	Day 3
71538Male	2.82	2.85	0.03
71584Male	2.11	2.20	0.09

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test item produced a maximum group mean score of 4.0 and was classified as a minimal irritant (Class 3 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system.
The test item did not meet the criteria for classification according to Regulation (EC) No. 1272/2008 on the classification, labelling and packaging of substances and mixtures.

Executive summary:

Introduction. The study was performed to assess the irritancy potential of the test item to the eye of the New Zealand White rabbit. The method was designed to be compatible with the following:

OECD Guidelines for the Testing of Chemicals No.405 "Acute Eye Irritation/Corrosion" (adopted 24 April 2002)

Method B5 Acute Toxicity (Eye Irritation) of Commission Regulation (EC) No.440/2008

Result. A single application of the test item to the non-irrigated eye of two rabbits produced minimal conjunctival irritation. Both treated eyes appeared normal at the 48‑Hour observation.

Conclusion. The test item produced a maximum group mean score of 4.0 and was classified as a minimal irritant (Class 3 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system.

The test item did not meet the criteria for classification according to Regulation (EC) No. 1272/2008 on the classification, labelling and packaging of substances and mixtures.