Reaction products of 4-alkylalkanol and diphosphorus pentaoxide with 2-ethylhexylamine

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Experimental start date: 11 February 2016 Experimental completion date: 11 February 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: The Rabbit Enucleated Eye Test

Version / remarks:

The Rabbit Enucleated Eye Test has been included in evaluations of the validity of eye irritancy test methods, but is not currently considered to be a validated 'stand-alone' test method. No formally adopted test guideline is available, but a protocol has been proposed which was based upon the method detailed in this document (ICCVAM, 2006 and 2009).

A positive result in the rabbit enucleated eye test is accepted within the EU as an indication of severe eye irritancy potential without the need for confirmation in a rabbit eye irritation test (European Chemicals Bureau, 2006).

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Test material form:

other: yellow semi-solid

Test animals / tissue source

Species:

rabbit

Strain:

not specified

Details on test animals or tissues and environmental conditions:

New Zealand White (Hsdlf:NZW) strain rabbits were supplied by Envigo RMS (UK) Limited, Leicestershire, UK. At the start of the study the animals were 12 to 20 weeks old. Rabbits that have previously been used in skin or eye irritation studies at the test facility may. be used as eye donors. If the donor animals have been used in an eye irritation study, only the untreated eyes were used.

Test system

Vehicle:

unchanged (no vehicle)

Remarks:

For the purpose of the study the test item was used as supplied.

Controls:

yes

yes, concurrent no treatment

Amount / concentration applied:

Three eyes were treated with the test item. Two additional eyes remained untreated for control purposes. The treatment eye was removed from the superfusion apparatus whilst still being held in the perspex clamp. The clamp/eye was then placed horizontally into a petri dish.

The test item was used undiluted as supplied.
A volume of 0.1 mL of the test item was applied as evenly as possible to the surface of the cornea

Duration of treatment / exposure:

After ten seconds the test item was washed off the cornea using a minimum of 20 mL of 0.9% saline solution (pre-warmed to approximately 32 °C).

Immediately following washing of the corneal surface, the treated eye was returned to the superfusion chamber and the saline drip repositioned to irrigate the eye.

The untreated eyes were similarly washed and used for control purposes.

Duration of post- treatment incubation (in vitro):

Immediately following washing of the corneal surface, the treated eye was returned to the superfusion chamber and the saline drip repositioned to irrigate the eye.

Number of animals or in vitro replicates:

5 eyes

Details on study design:

Please see below

Results and discussion

In vitro

Results

Results 1

Irritation parameter:

percent corneal swelling

Remarks:

Mean Corneal Swelling

Run / experiment:

60 runs

Value:

31.3

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

positive indication of irritation

Results 2

Irritation parameter:

percent corneal swelling

Remarks:

Mean Corneal Swelling

Run / experiment:

120 runs

Value:

54.7

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

positive indication of irritation

Results 3

Irritation parameter:

percent corneal swelling

Remarks:

Mean Corneal Swelling

Run / experiment:

240 runs

Value:

90

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

positive indication of irritation

Any other information on results incl. tables

Corneal Opacity

Individual scores for corneal opacity are given in the attached Appendix 1.

Some loss of transparency was noted in all test eyes. No corneal effects were noted in the control eyes during the study period.

Corneal Thickness

Individual and mean measurements for corneal thickness are given in the attached Appendix 2. The determination of corneal swelling is given in Table 1 and Table 2. The calculated mean corneal swellings are given in Table 3.

Corneal swelling of the test eyes was considerably greater than that observed in the control eyes over the same period and exceeded the 2.25% cut-off value.

Corneal Condition

The condition of the corneal epithelium following treatment is given in the attached Appendix 3.

Sloughing of the corneal epithelium was noted in test eyes. The condition of the corneal epithelium of the control eyes appeared normal during the study.

Fluorescein Uptake

Individual scores for fluorescein uptake are given in the attached Appendix 4.

Fluorescein uptake was noted in the test eyes 240 minutes following test item application. No fluorescein uptake was noted in the control eyes 240 minutes following treatment.

Table 1            Determination of Corneal Swelling-Test Eyes

Chamber Number	Observation Period (minutes)	Mean Corneal Thickness(µm)	Corneal Swelling(%)a	Chamber Number	Observation Period (minutes)	Mean Corneal Thickness(µm)	Corneal Swelling(%)a	Chamber Number	Observation Period (minutes)	Mean Corneal Thickness(µm)	Corneal Swelling(%)a
IA	Post equilibration	355.8	na	3A	Post equilibration	400.0	na	5A	Post equilibration	414.2	na
	60 Post treatment	520.2	46.2		60 Post treatment	514.0	28.5		60 Post treatment	493.8	19.2
	120 Post treatment	643.8	80.9		120 Post treatment	578.4	44.6		120 Post treatment	573.6	38.5
	180 Post treatment	771.6	116.9		180 Post treatment	612.8	53.2		180 Post treatment	633.8	53.0
	240 Post treatment	854.0	140.0		240 Post treatment	655.4	63.9		240 Post treatment	688.6	66.2

a = % corneal swelling = (mean corneal thickness post-treatment) - (mean corneal thickness post equilibration) / mean corneal thickness post equilibrium x 100

Na = Not applicable

Table2            Determination of Corneal Swelling - Control Eyes

ChamberNumber	Observation Period (minutes)	Mean Corneal Thickness (µm)	Corneal Swelling(%)a	Chamber Number	Observation Period(minutes)	Mean Corneal Thickness (µm)	Corneal Swelling(%)a
2A	Post equilibration	353.0	na	4A	Post equilibration	403.8	na
	60 Post treatment	368.4	4.4		60 Post treatment	449.8	11.4
	120 Post treatment	356.4	1.0		120 Post treatment	472.6	17.0
	180 Post treatment	350.4	0.0		180 Post treatment	468.4	16.0
	240 Post treatment	348.6	0.0		240 Post treatment	466.6	15.6

a = % corneal swelling = (mean corneal thickness post-treatment) - (mean corneal thickness post equilibration) / mean corneal thickness post equilibrium x 100

Na = Not applicable

Table3            Mean Corneal Swelling

	Time After Treatment
	60 minutes	120 minutes	240 minutes
Test Eyes	31.3+	54.7+	90.0+
Control Eyes	7.9	9.0	7.8

+ = Meets or exceeds cut-off value indicating a severe ocular irritant

Applicant's summary and conclusion

Interpretation of results:

Category 1 (irreversible effects on the eye) based on GHS criteria

Conclusions:

Following assessment of the data for all endpoints, the test item was considered to have the potential to cause severe ocular irritancy in viva.

Executive summary:

Introduction

 Itis a legal and ethical duty under the Animals (Scientific Procedure) Act 1986 that, in the interest of animal welfare, the unnecessary use of animals is avoided, and that any testing which is likely to produc esevere responses in animals is minimized.

 Therefore, before in vivo irritation testing is performed, all existing information on the test item, or its analogues should be reviewed. Available information indicated that the test item had the potential to produce severe effects in a rabbit eye and to confirm this initial assessment, a Rabbit Enucleated Eye Test (REET) was performed.

 

This step-wise procedure is in accordance with OECD Test Guideline 405,UK Home Office regulations and Envigo Research Limited Ethical Testing Strategy.

A study was performed to assess the ocular irritancy potential of the test item in the rabbit following application onto the cornea of the enucleated eye. The results of the study are believed to be of value in predicting the ocular irritation potential of the test item in man.

 

Method

 0.1 mL of the test item was applied onto the cornea of each of three enucleated eyes which had been maintained at a temperature of 32 ±1.5 °C within the superfusion chamber. A further two enucleated eyes remained untreated for control purposes.

Results

 Maximal ocular irritation observations recorded for the test eyes were as follows:

 

Corneal Opacity	FluoresceinUptake	Mean Corneal Swelling(%)						Condition of Corneal Epithelium
		Test Eyes a			Control Eyes b
Cldy x Area	Int x Area	60 ruins	120 ruins	240 ruins	60 ruins	120 ruins	240 ruins
3	4+	31.3+	54.7+	90.0+	7.9	9.0	7.8	sloughing+

 

  

a=          For each time point the swelling recorded is the mean of three eyes

b=         For each time point the swelling recorded is the mean of two eyes

Cldy =   Corneal cloudiness

Int=       Intensity of fluoresceinuptake

mms = Minutes following treatment

+=         Meets or exceeds cut-off value indicating a severe ocular irritant

 

Conclusion

 Following assessment of the data for all endpoints the test item was considered to have the potential to cause severe ocular irritancy in vivo.