Aluminium orthophosphate

Endpoint summary

Description of key information

Skin irritation: In accordance with the testing strategy detailed in Annex VIII, column 1 of Regulation (EC) No. 1907/2006 the assessment of the endpoint ‘skin irritation or skin corrosion’ has been performed following the consecutive steps detailed in the Regulation. As such an in vitro skin corrosion study has been performed. This study is not considered as the key study because it is not sufficient for classification and labelling in accordance with Regulation (EC) No. 1272/2008 (EU CLP) and is therefore submitted as supporting data. The key study (Warren N, 2010) is conducted according to an appropriate validated in vitro guideline and under the conditions of GLP and therefore the study is considered to be acceptable and to adequately satisfy both the guideline requirement and the regulatory requirement as a key study for this endpoint. In addition, the data is considered to be adequate and reliable for classification and labelling in accordance with Regulation (EC) No. 1272/2008 (EU CLP). 
Eye irritation: In accordance with the testing strategy detailed in Annex VIII, column 1 of Regulation (EC) No. 1907/2006 (REACH) an in vitro study has been performed prior to conducting an in vivo study. This study is not considered as the key study because it is not sufficient for classification and labelling in accordance with Regulation (EC) No. 1272/2008 (EU CLP). The key study (Bradshaw J, 2010) is conducted according to an appropriate guideline and under the conditions of GLP and therefore the study is considered to be acceptable and to adequately satisfy the regulatory requirement as a key study for this endpoint.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

The study was performed between 19 January 2010 and 25 January 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: EU Guideline Testing of Chemicals B46

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: OECD Draft Test Guideline (version 4)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Date of inspection: 15-09-2009 Date of Signature: 26-11-2009

Species:

other: reconstituted human epidermis model

Strain:

other: reconstituted human epidermis model

Details on test animals or test system and environmental conditions:

Not applicable

Type of coverage:

other: Topical

Preparation of test site:

other: Not applicable

Vehicle:

other: No vehicle used

Controls:

no

Amount / concentration applied:

TEST MATERIAL

- The test Material was applied neat.

- Amount(s) applied (volume or weight with unit):
10 ± 2 mg of the test material was applied to the epidermis surface pre-moistened with 5 µl of sterile distilled water.

- Concentration (if solution):
The test material was used as supplied.

VEHICLE
No vehicle used

Duration of treatment / exposure:

15 Minutes & 42 hour post exposure incubation

Observation period:

Not applicable

Number of animals:

Not applicable

Details on study design:

TEST SITE
- Area of exposure:
10 ± 2 mg of the test material was applied to the epidermis surface pre-moistened with 5 µl of sterile distilled water.

- % coverage:
The test material was applied topically to the corresponding tissues ensuring uniform covering.

- Type of wrap if used:
None used

REMOVAL OF TEST SUBSTANCE
- Washing (if done):
At the end of the exposure period, each tissue was removed from the well using forceps and rinsed using a wash bottle containing PBS with Ca++ and Mg++. Rinsing was achieved by filling and emptying each tissue insert for approximately 40 seconds using a constant soft stream of PBS to gently remove any residual test material.

- Time after start of exposure:
15 Minutes post exposure

SCORING SYSTEM:
Quantitative MTT Assessment (percentage tissue viability)
For the test material the relative mean tissue viabilities obtained after the 15 minute treatment followed by the 42 hour post-exposure incubation period were compared to the mean of the negative control treated tissues (n=3). The relative mean viabilities were calculated in the following way:

mean OD540 of test material / mean OD540 of negative control x 100 = Relative mean tissue viability (percentage of negative control)

Classification of irritation potential is based upon relative tissue viability following the 15 minute exposure period followed by the 42 hour post-exposure incubation period according to the following:

Mean tissue viability is ≤50% : Irritant (I) R38

Mean tissue viability is >50% : Non-Irritant (NI)

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

mean

Value:

99.6

Vehicle controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

The relative mean viability of the test material treated tissues was 99.9% after a 15-minute exposure.

RESULTS

Direct MTT Reduction

The MTT solution containing the test material did not turn blue/purple which indicated that the test material did not directly reduce MTT.

Test Material, Positive Control Material and Negative Control Material

The individual and mean OD₅₄₀ values, standard deviations and tissue viabilities for the test material, negative control material and positive control material are given in Table 1. The mean viabilities and standard deviations of the test material and positive control, relative to the negative control are also given in Table 1.

The relative mean viability of the test material treated tissues was 99.9% after a 15 minute exposure.

The qualitative evaluation of tissue viability is given in Table 2.

Following the 15-minute exposure the test material treated tissues appeared blue/white which was considered indicative of viable tissue.

Quality Criteria

The relative mean tissue viability for the positive control treated tissues was ≤40% relative to the negative control treated tissues and the standard deviation value of the percentage viability was ≤20%. The positive control acceptance criterion was therefore satisfied.

The mean OD₅₄₀ for the negative control treated tissues was ≥0.6 and the SD value of the percentage viability was ≤20%. The negative control acceptance criterion was therefore satisfied.

Table1 : Mean OD₅₄₀ Values and Percentage Viabilities for the Negative Control Material, Positive Control Material and Test Material

Material	OD540of tissues	Mean OD540of triplicate tissues	±SDof OD540	Relative individual tissue viability (%)	Relative mean viability (%)	± SD of Relative mean viability (%)
Negative Control Material	0.787	0.825	0.054	95.4	100*	6.6
	0.887			107.5
	0.801			97.1
Positive Control Material	0.037	0.033	0.005	4.5	4.0	0.6
	0.034			4.1
	0.027			3.3
Test Material	0.840	0.824	0.022	101.8	99.9	2.7
	0.799			96.8
	0.834			101.1

SD=    Standard deviation

*=     The mean viability of the negative control tissues is set at 100%

Table2 : Qualitative Evaluation of Tissue Viability (MTT uptake visual evaluation)

Material	Tissue 1	Tissue 2	Tissue 3
Negative Control Material	-	-	-
Positive Control Material	++	++	++
Test Material	-	-	-

MTT visual scoring scheme
-          =         blue tissue (viable)
+         =         blue/white tissue (semi-viable)
++       =         tissue is completely white (dead)

Interpretation of results:

not irritating

Conclusions:

The test material was considered to be Non-Irritant (NI)
This study is conducted according to an appropriate validated in vitro guideline and under the conditions of GLP and therefore the study is considered to be acceptable and to adequately satisfy both the guideline requirement and the regulatory requirement as a key study for this endpoint. In addition, the data is considered to be adequate and reliable for classification and labelling in accordance with Regulation (EC) No. 1272/2008 (EU CLP).

Executive summary:

Introduction.

The purpose of this test was to evaluate the skin irritation potential of the test material using the EPISKINTM reconstituted human epidermis model after a treatment period of 15 minutes followed by a post-exposure incubation period of 42 hours. The principle of the assay was based on the measurement of cytotoxicity in reconstituted human epidermal cultures following topical exposure to the test material by means of the colourimetric MTT reduction assay. Cell viability is measured by enzymatic reduction of the yellow MTT tetrazolium salt (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) to a blue formazan salt (within the mitochondria of viable cells) in the test material treated tissues relative to the negative controls. The concentration of the inflammatory mediator IL-1α in the culture medium retained following the 42 hour post-exposure incubation period is also determined for test materials which are found to be borderline non-irritant based upon the MTT reduction endpoint. This complimentary end-point will be used to either confirm a non-irritant result or will be used to override the non-irritant result.

Triplicate tissues were treated with the test material for an exposure period of 15 minutes. At the end of the exposure period each tissue was rinsed before incubating for approximately 42 hours. At the end of the post-exposure incubation period each tissue was taken for MTT-loading. The maintenance medium from beneath each tissue was transferred to pre-labelled micro tubes and stored in a freezer for possible inflammatory mediator determination. After MTT loading a total biopsy of each epidermis was made and placed into micro tubes containing acidified isopropanol for extraction of formazan crystals out of the MTT-loaded tissues.

At the end of the formazan extraction period each tube was mixed thoroughly and duplicate 200 μl samples were transferred to the appropriate wells of a pre-labelled 96-well plate. The optical density was measured at 540 nm.

Data are presented in the form of percentage viability (MTT reduction in the test material treated tissues relative to negative control tissues).

Results: The relative mean viability of the test material treated tissues was 99.9% after a 15-minute exposure.

Quality criteria: The quality criteria required for acceptance of results in the test were satisfied.

Conclusion: The test material was considered to be Non-Irritant (NI).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Remarks:

Study was performed prior to the update of the REACH Regulation and prior to the validation of in vitro test methods.

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

The study was performed between 12 May 2010 and 21 May 2010.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Date of GLP inspection: 15/09/2009 Date of Signature on GLP certificate: 26/11/2009

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories U.K. Ltd., Loughborough, UK.

- Age at study initiation: Twelve to twenty weeks old

- Weight at study initiation: 2.31 to 2.47 kg

- Housing: The animals were individually housed in suspended cages. 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.

- Diet (e.g. ad libitum): ad libitum (2030 Teklad Global Rabbit diet supplied by Harlan Laboratories U.K. Ltd., Oxon, UK)

- Water (e.g. ad libitum): ad libitum.

- Acclimation period: At least five days


ENVIRONMENTAL CONDITIONS

- Temperature (°C): 17 to 23°C

- Humidity (%): 30 to 70%

- Air changes (per hr): At least fifteen changes per hour

- Photoperiod (hrs dark / hrs light): Twelve hours continuous light (06:00 to 18:00) and twelve hours darkness


IN-LIFE DATES: From: day 1 To:day 3

Vehicle:

unchanged (no vehicle)

Controls:

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

Amount / concentration applied:

TEST MATERIAL

- Amount(s) applied (volume or weight with unit): A volume of 0.1 ml of the test material, which was found to weigh approximately 98 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.

- Concentration (if solution): Undiluted and used as supplied

Observation period (in vivo):

Assessment of ocular damage/irritation was made approximately 1 hour and 24, 48 and 72 hours following treatment.

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, one additional animals was treated. )

Details on study design:

REMOVAL OF TEST SUBSTANCE

- Washing (if done):
Not applicable

- Time after start of exposure:
Not applicable


SCORING SYSTEM:
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).


TOOL USED TO ASSESS SCORE:

Examination of the eye was facilitated by the use of the light source from a standard ophthalmoscope.

Irritation parameter:

cornea opacity score

Basis:

animal: 69198 Male

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: No effects observed

Irritation parameter:

cornea opacity score

Basis:

animal: 69234 Male

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: No effects observed

Irritation parameter:

iris score

Basis:

animal: 69198 Male

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

other: No effect observed

Irritation parameter:

iris score

Basis:

animal: 69234 Male

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

other: No effect observed

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal: 69198 Male

Time point:

24/48/72 h

Score:

0.66

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal: 69234 Male

Time point:

24/48/72 h

Score:

0.66

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

chemosis score

Basis:

animal: 69198 Male

Time point:

24/48/72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 hours

Irritation parameter:

chemosis score

Basis:

animal: 69234 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 or iridial effects were noted during the test.
Moderate conjunctival irritation was noted in both treated eyes one hour after treatment with minimal conjunctival irritation noted at the 24 and 48-Hour observations.
Both treated eyes appeared normal at the 72-Hour observation.

Other effects:

Body weight
Both animals showed expected gain in bodyweight during the study.

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 ( Modified Kay and Calandra Interpretation of Eye Irritation Test was used to classify the ocular irritancy potential of the test material. 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 material.

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

Table1               IndividualScores and Individual Total Scoresfor Ocular Irritation

Rabbit Number and Sex	69198 Male				69234 Male
	IPR= 2				IPR = 2
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	2	1	1	0	2	1	1	0
B = Chemosis	2	1	0	0	2	1	0	0
C = Discharge	2	1	0	0	2	1	0	0
Score (A + B + C) x 2	12	6	2	0	12	6	2	0
Total Score	12	6	2	0	12	6	2	0

 

IPR=  Initial pain reaction

Table 2               Individual Total Scores and Group Mean Scoresfor Ocular Irritation

Rabbit Number and Sex	Individual Total Scores At:
	1 Hour	24 Hours	48 Hours	72 Hours
69198 Male	12	6	2	0
69234 Male	12	6	2	0
Group Total	24	12	4	0
Group Mean Score	12.0	6.0	2.0	0.0

Interpretation of results:

GHS criteria not met

Conclusions:

The test material did not meet the criteria for classification as irritant according to Regulation (EC) No. 1272/2008 (EU CLP). This study is conducted according to the appropriate guidelines (EU ) and under the conditions of GLP and therefore the study is considered to be acceptable and to adequately satisfy both the guideline requirement and the regulatory requirement as a key study for this endpoint. Study is sufficient for classification and labelling purposes, 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 material to the eye of the New Zealand White rabbit. The method was designed to meet the requirements of 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 material to the non-irrigated eye of two rabbits produced moderate conjunctival irritation. Both treated eyes appeared normal at the 72-Hour observation.

Conclusion. The test material produced a maximum group mean score of 12.0 and was classified as a mild irritant (Class 4 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Justification for selection of skin irritation / corrosion endpoint:
One key study available. This study is conducted according to the appropriate guidelines (OECD 439) and under the conditions of GLP and therefore the study is considered to be acceptable and to adequately satisfy both the guideline requirement and the regulatory requirement for REACH (Regulation (EC) No.1907/2006) as a key study for this endpoint. Study is sufficient for classification and labelling purposes, in accordance with Regulation (EC) No. 1272/2008 (EU CLP).

Justification for selection of eye irritation endpoint:
One key study available. This study is conducted according to the appropriate guidelines (OECD 405) and under the conditions of GLP and therefore the study is considered to be acceptable and to adequately satisfy both the guideline requirement and the regulatory requirement for REACH (Regulation (EC) No.1907/2006) as a key study for this endpoint. Study is sufficient for classification and labelling purposes, in accordance with Regulation (EC) No. 1272/2008 (EU CLP).

Justification for classification or non-classification

Skin irritation: The data available to assess the skin irritation potential of aluminium orthophosphate concludes that the substance is not classified as irritating to the skin in accordance with Regulation (EC) No. 1272/2008 (EU CLP). It is not considered scientifically justified on ethical grounds to repeat in vivo studies for this endpoint as the data provided is sufficient.

Eye irritation: The data available to assess the eye irritation potential of aluminium orthophosphate concludes that the substance is not classified as irritating to the eyes in accordance with Regulation (EC) No. 1272/2008 (EU CLP). It is not considered scientifically justified on ethical grounds to repeat in vivo studies for this endpoint as the data provided is sufficient.

Respiratory irritation: There are no data available (workplace observations or studies) to suggest that aluminium orthophosphate is a respiratory irritant.