Strontium tartrate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

November 3, 2014 - November 4, 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study has been performed according to OECD and/or EC guidelines and according to GLP principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying Ocular Corrosives and Severe Irritants)

Version / remarks:

(2013)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU method B.47 (Bovine corneal opacity and permeability test method for identifying ocular corrosives and severe irritants)

Version / remarks:

(2010)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: The Ocular Toxicity Working Group (OTWG) of ICCVAM and NICEATM, Background Review Document (BRD): current status of in vitro test methods for identifying ocular corrosives and severe irritants: The BCOP Test Method, March 2006

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: In Vitro Techniques in Toxicology Database (INVITTOX) protocol 127. Bovine Opacity and Permeability (BCOP) Assay, 2006

Deviations:

no

Test guideline 5

Qualifier:

according to guideline

Guideline:

other: Gautheron P., Dukic M., Alix D. and Sina J.F., Bovine corneal opacity and permeability test: An in vitro assay of ocular irritancy. Fundam Appl Toxicol 18:442-449, 1992

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Strontium tartrate

EC Number:

212-774-9

EC Name:

Strontium tartrate

Cas Number:

868-19-9

Molecular formula:

C4H4O6Sr

IUPAC Name:

strontium(2+) 2,3-dihydroxybutanedioate

Details on test material:

- Name of test material (as cited in study report): Strontium tartrate (anhydrous)
- Appearance: Off-white powder

Test system

Vehicle:

unchanged (no vehicle)

Amount / concentration applied:

TEST MATERIAL
- Since no workable suspension in physiological saline could be obtained, the test substance was added on top of the corneas, in such a way that the cornea was completely covered
- Amount applied: 317 to 360 mg per cornea

NEGATIVE CONTROL
- Amount applied: 750 µL of physiological saline per cornea

POSITIVE CONTROL
- Amount applied: 750 µL of a 20% (w/v) Imidazole solution in physiological saline per cornea

Duration of treatment / exposure:

4 hours

Details on study design:

TEST SITE
- Isolated bovine cornea
- Three corneas were used for each treatment group
- The corneas were incubated at 32 ± 1°C

REMOVAL OF TEST SUBSTANCE
- Washing: yes, with MEM+phenol red
- Time after start of exposure: 4 hours

SCORING SYSTEM:
- After exposure, the cornea is thoroughly rinsed to remove the test substance followed by immediate opacity measurement
- Following the final opacity measurement, permeability of the cornea to Na-fluorescein (Merck) was evaluated (90 minutes incubation)
- After the incubation period, permeability evaluation of the cornea was performed
- The mean opacity and mean permeability values (OD490) were used for each treatment group to calculate the mean in vitro score:
Mean in vitro irritancy score (IVIS) = mean opacity value + (15 x mean OD490 value).
- Opacity and permeability values were also evaluated individually

TOOL USED TO ASSESS SCORE:
- Opacitymeter and microplate reader

DATA EVALUATION:
- A test substance that induces a mean IVIS >55 is classified with Eye Irr. Cat. 1 in accordance with the CLP Regulation
- A test substance that induces a mean IVIS ≤ 3 is not classified for Eye irritation in accordance with the CLP Regulation
- For a test substance that induces a mean IVIS of >3 - ≤55, it cannot be concluded whether the substance needs to be classified or not and for these substances, more (in vivo) information is needed

Results and discussion

In vivo

Results

Irritation parameter:

other: In vitro irritancy score (IVIS)

Basis:

mean

Time point:

other: 4 hours

Score:

1.9

Remarks on result:

other: Negative control: 0; Positive control: 123.9

Any other information on results incl. tables

Summary of opacity, permeability and in vitro scores:

Treatment	Mean Opacity	Mean Permeability	Mean In vitro Irritation Score
Negative control	0.0	0.000	0.0
Positive control	90.3	2.237	123.9
Strontium tartrate (anhydrous)	0.3	0.105	1.9

Individual in vitro irritancy scores:

Eye	In vitro Irritancy Score
Negative control
1	0.0
2	-0.1
3	0.1
Positive control
13 (*)	131.3
5	108.8
6	131.5
Strontium tartrate (anhydrous)
10	1.8
11	0.9
12	3.1

 (*) Cornea 4 was replaced by cornea 13, since cornea 4 was damaged and discarded. Cornea 7, 8 and 9 were used for another test substance.

No pH effect of the test substance was observed on the rinsing medium.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Based on the results of a Bovine Corneal Opacity and Permeability test in which Strontium tartrate (anhydrous) did not induce ocular irritation (mean in vitro irritancy score of 1.9), Strontium tartrate (anhydrous) has no eye irritating properties and does not need to be classified for Eye irritation in accordance with the CLP Regulation.

Executive summary:

Using the Bovine Corneal Opacity and Permeability test (BCOP test) Strontium tartrate (anhydrous) was screened for its eye irritancy potential in accordance with OECD 437 and according to GLP principles. The substance was applied as such directly on top of the corneas in such a way that the cornea was completely covered (317 to 360 mg per cornea). Adequate negative and positive controls were included. The substance did not induce ocular irritation through both endpoints, resulting in a mean in vitro irritancy score of 1.9 after 240 minutes of treatment. Since the substance induced a mean IVIS ≤ 3, the substance does not need to be classified for Eye irritation in accordance with the CLP Regulation.