Barium europium strontium silicate

Endpoint summary

Description of key information

Under the experimental conditions reported, the test item is not irritating to the skin according to OECD 439.

The structural analogue substance caused severe eye damage according to OECD Guideline 437.

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:

key study

Study period:

August 24, 2011 - August 26, 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method B.46 (In Vitro Skin Irritation: Reconstructed Human Epidermis Model Test)

Version / remarks:

2009

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)

Version / remarks:

2010

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Skinethic Skin irritation test -42bis Standard operating procedure (SOP) 2009

Version / remarks:

2009

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Justification for test system used:

To reduce animal testing, this alternative in vitro method was used. The human skin RHE-model closely mimics the biochemical and physiological properties of the upper parts of the human skin, i.e the epidermis.

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: SkinEthic™ RHE-model
- Tissue batch number(s): 11 022A 0802
- Date of initiation of testing: August 24, 2011

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: room temperature
- Temperature of post-treatment incubation: 37°C

REMOVAL OF TEST MATERIAL AND CONTROLS
-Volume and number of washing steps: minimum volume of 25 mL PBS using a multi pipette


MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 1 mg/mL
- Incubation time: 3 hours
- Spectrophotometer: spectrophotometer
- Wavelength: 570 nm

NUMBER OF REPLICATE TISSUES:
3

NUMBER OF INDEPENDENT TEST SEQUENCES / EXPERIMENTS TO DERIVE FINAL PREDICTION:
One experiment in triplicate

PREDICTION MODEL / DECISION CRITERIA
- The test substance is considered to be irritant to skin if the viability after exposure is less than 50% or equal to 50 %.
- The test substance is considered to be non-irritant to skin if the viability after exposure is greater than 50%.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount applied: 16 mg

NEGATIVE CONTROL
- Amount applied: 16 µL

POSITIVE CONTROL
- Amount applied: 16 µL

Duration of treatment / exposure:

42 minutes

Duration of post-treatment incubation (if applicable):

42 hours

Number of replicates:

3

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Tissue 1/experiment 1

Value:

1.681

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Tissue 2/experiment 1

Value:

1.79

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Tissue 3/experiment 1

Value:

1.798

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

- OTHER EFFECTS:
- Visible damage on test system: no
- Direct-MTT reduction: no

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: Yes
- Acceptance criteria met for positive control: Yes
- Acceptance criteria met for variability between replicate measurements: Yes

Results

Dose group  treatment interval  optical density tissue1  optical density tissue 2  optical density tissue 3  MEAN optical density  mean relative viability [%] Standard deviation   negative control  42 min  1.768  1.598  1.878  1.748  100  8.06  positive control  42 min  0.057  0.049  0.057  0.054  3.11  8.32  test item  42 min  1.681  1.790  1.798  1.756  100.47  3.74

Interpretation of results:

GHS criteria not met

Conclusions:

The test substance is to be considered as non-irritating to the skin under the conditions of this experiment.

Executive summary:

In an in vitro skin irritation model, substance was tested. The applied cellline (RHE (Reconstructed Human Epidermis) is produced by SkinEthic by culturing human adult keratinocytes on a polycarbonate filter in such a quality that a functional stratum corneum is available and thermal differentation takes place. The test was conducted under GLP and according to OECD guideline 439, the EU Method B.46 and the Standard Operating Procedure of SkinEthic's (Skin irritation test -42bis).

Each test is performed in triplicates. 16µl of controls were directly applied to the tissue. Prior 16mg of test substance were applied, 10 µl of water were sprayed to the tissue. After treatment of (treatment time 42minutes at roomtemperature) substances were removed and tissues were incubated for 424 hours.

For testing validity of the Skin model, a positive control (5% sodiumdodecylsulfate in deionized water) and a negative control (PBS buffer) were used.

After topical exposure of test substance, positive control, or negative control cell viability is measured in a MTT assay. In this assay cell viability is measured by conversion of MTT to a formazan salt by a dehydrogenase enzyme.

As the test item has a very high cell viability of (100%) passing the threshold value of 50%, this item is to be considered as non-irritant. The test is valid since the criteria for the positive control (cell viability < 40%; 3,1% in this test) and the negative control (optical density between 1.2 and 2.5; 1.75 in this itest) are met.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Reference 1

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-11-20 to 2015-11-27

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Vehicle:

physiological saline

Controls:

yes, concurrent vehicle

yes, concurrent positive control

Amount / concentration applied:

750 µL (i.e. 150mg/750µL) of test item, negative or positive control

Duration of treatment / exposure:

240 minutes

Number of animals or in vitro replicates:

in vitro: triplicate design

Irritation parameter:

in vitro irritation score

Run / experiment:

run 1

Value:

113.9

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

positive indication of irritation

Irritation parameter:

cornea opacity score

Run / experiment:

run 1

Value:

62.2

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Irritation parameter:

fluorescein leakage

Run / experiment:

run 1

Value:

3.45

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

		Opacity	Permeability	IVIS
				per cornea	per group (mean value)	SD
Negative Control	0.9 % NaCl Solution	-0.062	-0.001	-0.082	0.8	0.9
		1.816	-0.001	1.801
		0.706	-0.001	0.696
Positive Control	20 % Imidazole  solution	70.793	2.142	102.928	106.6	4.1
		71.315	2.303	105.860
		79.270	2.119	111.060
Test material	20% suspension	66.507	3.447	118.217	113.9	16.4
		72.337	3.699	127.827
		47.660	3.206	95.780

Interpretation of results:

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

Conclusions:

Under the given experimental conditions the test material the test material has ocular corrosive potential.

Executive summary:

This study was performed according to GLP and the methods applied are fully compliant with OECD TG 437. The test material was corrosive in this in vitro assay.

Reference 2

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

For this endpoint information from a structural similar compound is available. This study for this similar compound was performed according to GLP and the methods applied are fully compliant with OECD TG 437. See chapter 13 report for a more detailed justification.

Reason / purpose for cross-reference:

read-across source

Irritation parameter:

in vitro irritation score

Run / experiment:

run 1

Value:

113.9

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

positive indication of irritation

Irritation parameter:

cornea opacity score

Run / experiment:

run 1

Value:

62.2

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Irritation parameter:

fluorescein leakage

Run / experiment:

run 1

Value:

3.45

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Interpretation of results:

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

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irreversible damage)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

In vitro skin irritation study

In an in vitro skin irritation model, substance was tested. The applied cell line (RHE (Reconstructed Human Epidermis) is produced by SkinEthic by culturing human adult keratinocytes on a polycarbonate filter in such a quality that a functional stratum corneum is available and thermal differentation takes place. The test was conducted under GLP and according to OECD guideline 439, the EU Method B.46 and the Standard Operating Procedure of SkinEthic's (Skin irritation test -42bis).

Each test is performed in triplicates. 16µl of controls were directly applied to the tissue. Prior 16 mg of test substance were applied, 10 µl of water were sprayed to the tissue. After treatment of (treatment time 42 minutes at room temperature) substances were removed and tissues were incubated for 42 hours.

For testing validity of the Skin model, a positive control (5% sodiumdodecylsulfate in deionized water) and a negative control (PBS buffer) were used.

After topical exposure of test substance, positive control, or negative control cell viability is measured in a MTT assay. In this assay cell viability is measured by conversion of MTT to a formazan salt by a dehydrogenase enzyme.

As the test item has a very high cell viability of (100%) passing the threshold value of 50%, this item is to be considered as non-irritant. The test is valid since the criteria for the positive control (cell viability < 40%; 3,1% in this test) and the negative control (optical density between 1.2 and 2.5; 1.75 in this itest) are met.

In vitro eye irritation study

The objective of the present study was to examine the potential of the structural analogue substance to induce serious eye damage in the BCOP assay. The BCOP assay with isolated fresh bovine corneas is an accepted in vitro model for ocular hazard assessment.

To determine the eye hazard potential the induced opacity and increased permeability was investigated in isolated bovine corneas after exposure to the test item as a 20% (w/v) suspension in a 0.9% sodium chloride solution. As negative control 0.9% sodium chloride solution and as positive control 20% (w/v) Imidazole was used. Three corneas were used per group (negative control, positive control or test item group).
After a first opacity measurement of the untreated bovine corneas, 750 µL of the suspended test item, positive or negative control were applied on the corneas and incubated for 240 minutes. After the incubation phase the test item, the positive, and the negative control were rinsed from the corneas and the opacity was measured again. After the opacity measurements, the permeability of the corneas was determined by application of a fluorescein solution for 90 minutes. The amount of fluorescein solution that crossed the cornea was measured spectrophotometrically. The opacity and permeability assessments were combined to determine an In Vitro Irritancy Score (IVIS).

After treatment with the negative control (0.9% sodium chloride solution) the calculated IVIS was 0.1 (study acceptance criteria range: -1.4 – 3.4). Treatment with the positive control (20% Imidazole) revealed an IVIS of 111.2 (study acceptance criteria range: 77.4 – 136.3). Therefore, the study fulfilled the validity criteria. The IVIS obtained after treatment with the test item was 113.9 and, thus, higher than 55.

Under the conditions of the present study, the test item induces serious eye damage in this in vitro assay.

Justification for classification or non-classification

Based on the data provided, the test item is not classified for skin irritation according to Regulation (EC) No 1272/2008. However, based on the results obtained from the structural analogue substance the test item is classified for severe eye damage cat. 1 and labelled with H318 according to Regulation (EC) No 1272/2008.