Iron orthophosphate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Between 20 December 2011 and 07 January 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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:

Iron orthophosphate

EC Number:

233-149-7

EC Name:

Iron orthophosphate

Cas Number:

10045-86-0

Molecular formula:

FePO4

IUPAC Name:

iron(3+) phosphate

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 2.57 or 2.86 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 (2930C Teklad Global 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:

yes, concurrent no treatment

Amount / concentration applied:

A volume of 0.1 mL of the test item, which was found to weigh approximately 94 mg

Duration of treatment / exposure:

Up to 1 hour

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

2 animals were tested in total. (After consideration of the ocular responses produced in the first treated animal, an additional animal was treated. )

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, which was found to weigh approximately 94 mg (as measured by gently compacting the required volume into an adapted syringe) 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. In order to minimise pain on application of the test item, one drop of local anaesthetic (Tetracaine hydrochloride 0.5%, Bausch & Lomb, Surrey, UK) was instilled into both eyes of the second animal 1 to 2 minutes before treatment.
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: 71491 Male

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: No effects observed

Results 2

Irritation parameter:

cornea opacity score

Basis:

animal: 71516 Male

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: No effects observed

Results 3

Irritation parameter:

iris score

Basis:

animal: 71491 Male

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

other: no effects observed

Results 4

Irritation parameter:

iris score

Basis:

animal: 71516 Male

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

other: No effects observed

Results 5

Irritation parameter:

conjunctivae score

Basis:

animal: 71491 Male

Time point:

24/48/72 h

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Results 6

Irritation parameter:

conjunctivae score

Basis:

animal: 71516 Male

Time point:

24/48/72 h

Score:

0.66

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Results 7

Irritation parameter:

chemosis score

Basis:

animal: 71491 Male

Time point:

24/48/72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 hours

Results 8

Irritation parameter:

chemosis score

Basis:

animal: 71516 Male

Time point:

24/48/72 h

Score:

0.33

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 effects were noted during the study.
Iridial inflammation was noted in one treated eye one hour after treatment.
Moderate conjunctival irritation was noted in both treated eyes one hour after treatment. Moderate conjunctival irritation was noted in one treated eye and minimal conjunctival irritation was noted in the other treated eye at the 24 Hour observation. Minimal conjunctival irritation was noted in both treated eyes at the 48 Hour observation.
Both treated eyes appeared normal at the 72-Hour observation.

Other effects:

Bodyweight
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

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), J. Soc. Cosmet. Chem.13, 281‑289 (seeAppendix3) 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 the Regulation (EC) No 1272/2008, relating to the Classification, Labelling and Packaging of Dangerous Substances.

Table 1              Individual Scores and Individual Total Scores for Ocular Irritation

Rabbit Number and Sex	71491 Male				71516 Male
	IPR= 3				IPR= 0+
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	1	0	0	0	0	0	0	0
Score (D x 5)	5	0	0	0	0	0	0	0
CONJUNCTIVAE
A = Redness	2	2	1	0	2	1	1	0
B = Chemosis	2	1	0	0	1	1	0	0
C = Discharge	2	1	0	0	1	0	0	0
Score (A + B + C) x 2	12	8	2	0	8	4	2	0
Total Score	17	8	2	0	8	4	2	0

IPR=  Initial pain reaction

+=     One drop of local anaesthetic instilled into both eyes 1 to 2 minutes before treatment

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
71491 Male	17	8	2	0
71516 Male	8	4	2	0
Group Total	25	12	4	0
Group Mean Score	12.5	6.0	2.0	0.0

Table 3              Individual Bodyweights and Bodyweight Changes

Rabbit Number and Sex	Individual Bodyweight (kg)		Bodyweight Change (kg)
	Day 0	Day 3
71491 Male	2.57	2.68	0.11
71516 Male	2.86	2.96	0.10

Applicant's summary and conclusion

Interpretation of results:

other: CLP/EU GHS criteria are not met, no classification required according to Regulations (EC) No 1272/2008

Conclusions:

The test item does not meet the criteria for classification according to the Regulation (EC) No 1272/2008 (EU CLP).
This study is considered to be scientifically justified for use as a key study under Regulation (EC) No. 1907/2006 and the results are appropriate for the purposes of classification and labelling in accordance with Regulation (EC) No. 1272/2008 (EU CLP).

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 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 12.5 and was classified as a mild irritant (Class4 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system.

The test item does not meet the criteria for classification according to the Regulation (EC) No 1272/2008, relating to the Classification, Labelling and Packaging of Dangerous Substances.