Silicic acid (H4SiO4), tetraethyl ester, reaction products with bis(acetyloxy)dioctylstannane

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2 May 2012 - 4 May 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was performed to the standardised guidelines OECD 431 and EU Method B.40 and in line GLP. The study was reported to a high standard, sufficient to assess the quality of the data presented.

Justification for data waiving:

other:

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 431 (In Vitro Skin Corrosion: Human Skin Model Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.40 (In Vitro Skin Corrosion: Transcutaneous Electrical Resistance Test (TER))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Dioctyltin oxide

EC Number:

212-791-1

EC Name:

Dioctyltin oxide

Cas Number:

870-08-6

IUPAC Name:

dioctyl(oxo)stannane

Test material form:

other: solid (not specified)

Details on test material:

- Name of test material (as cited in study report): Di-n-octyltin oxide
- Physical state: white solid
- Storage conditions: room temperature in the dark

Test animals

Details on test animals or test system and environmental conditions:

EPISKIN Model Kit 0.38 cm2
Supplier: SkinEthic Laboratories, Nice, France

Test system

Amount / concentration applied:

20 mg of the solid test item was applied topically.

Duration of treatment / exposure:

3, 60 and 240 minutes.

Observation period:

3 hours ± 5 minutes

Number of animals:

Not applicable

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

other: other: OD540

Value:

0.238

Remarks on result:

other:

Remarks:

Basis: mean. Time point: 240 minutes. Max. score: 0.224. (migrated information)

Results 2

Irritation / corrosion parameter:

other: other: OD540

Value:

0.244

Remarks on result:

other:

Remarks:

Basis: mean duplicate tissues. Time point: 60 minutes. Max. score: 0.224. (migrated information)

Results 3

Irritation / corrosion parameter:

other: other: OD540

Value:

0.296

Remarks on result:

other:

Remarks:

Basis: mean duplicate tissues. Time point: 3 minutes. Max. score: 0.224. (migrated information)

Results 4

Irritation / corrosion parameter:

other: other: Relative mean viability (%)

Value:

106.3

Remarks on result:

other:

Remarks:

Basis: mean duplicate tissues. Time point: 240 minutes. Max. score: 100.0. (migrated information)

Results 5

Irritation / corrosion parameter:

other: other: Relative mean viability (%)

Value:

108.9

Remarks on result:

other:

Remarks:

Basis: mean duplicate tissues. Time point: 60 minutes. Max. score: 100.0. (migrated information)

Results 6

Irritation / corrosion parameter:

other: other: Relative mean viability (%)

Value:

132.1

Remarks on result:

other:

Remarks:

Basis: mean duplicate tissues. Time point: 3 minutes. Max. score: 100.0. (migrated information)

Any other information on results incl. tables

Direct MTT Reduction

The MTT solution containing the test item did not turn blue. This was taken to indicate the test item did not reduce MTT.

 

Test Item, Positive Control Item and Negative Control Item

Mean OD540 values and viabilities for the negative control, positive control and test item are given in Table 1.

The relative mean viability of the test item treated tissues was as follows:

240 minutes exposure: 106.3 %

60 minutes exposure: 108.9 %

3 minutes exposure: 132.1%

Quality Criteria

The relative mean tissue viability for the positive control treated tissues was 1.3 % relative to the negative control treated tissues following the 240 minute exposure period. The positive control acceptance criterion was therefore satisfied.

The mean OD540 for the negative control treated tissues was 0.224. The negative control acceptance criterion was therefore satisfied.

 

Table 1 Mean OD540 Values and Viabilities for the Negative Control Item, Positive Control Item and Test Item

Item	Exposure Period (Minutes)	Mean OD540 of Duplicate Tissues	Relative Mean Viability %
Negative Control Item	240	0.224	100*
Positive Control Item	240	0.003	1.3
Test Item	240	0.238	106.3
	60	0.244	108.9
	3	0.296	132.1

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

Applicant's summary and conclusion

Interpretation of results:

other: under the conditions of the test, the test substance can be considered not to require a classification for corrosion. Irritancy cannot be assessed with this method.

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

The test item was considered to be Non-Corrosive to the skin.

Executive summary:

The purpose of the test was to evaluate the corrosivity potential of the test item using the EPISKIN in vitro Reconstructed Human Epidermis (RHE) Model. This method was designed to be compatible with theOECD Guideline for the Testing of Chemicals No. 431 “In Vitro Skin Corrosion: Human Skin Model Test” (adopted 13 April 2004) and Method B.40 of Commission Regulation (EC) No. 440/2008.

 

Duplicate tissues were treated with the test item for exposure periods of 3, 60 and 240 minutes. At the end of the exposure period the test item was rinsed from each tissue before each tissue was taken for MTT-loading. 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 (OD) was measured at 540 nm (OD540).

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

 

The relative mean viability of the test item treated tissues were:

240 minutes exposure: 106.3 %

60 minutes exposure: 108.9 %

3 minutes exposure: 132.1 %

The test item was considered to be Non-Corrosive to the skin.