Silane, triethyl[[4-(triethylsilyl)-3-butyn-1-yl]oxy]-

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2014-06-17 to 2014-06-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

The study described in this report has been correctly reported and was conducted in compliance with: The Organization for Economic Co-operation and Development (OECD) Principles of Good Laboratory Practice (GLP) (as revised in 1997) ENV/MC/CHEM (98) 17.

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

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

triethyl({[4-(triethylsilyl)but-3-yn-1-yl]oxy})silane

EC Number:

605-200-7

Cas Number:

160194-28-5

Molecular formula:

C16H34OSi2

IUPAC Name:

triethyl({[4-(triethylsilyl)but-3-yn-1-yl]oxy})silane

Test material form:

gas under pressure: refrigerated liquefied gas

Details on test material:

- Name of test material (as cited in study report): Bis-Tes (dried)
- Molecular formula (if other than submission substance): C16H34OSi2
- Molecular weight (if other than submission substance): 298
- Physical state: Pale yellow liquid
- Storage condition of test material: At room temperature in the dark under nitrogen
- Other:

Test animals

Species:

other: in vitro human skin model

Details on test animals or test system and environmental conditions:

Human Skin Model

Test system

Type of coverage:

not specified

Preparation of test site:

not specified

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 25 µl
- Concentration (if solution): Undiluted

Duration of treatment / exposure:

15 minutes

Observation period:

42 hour

Number of animals:

The test was performed on a total of 3 tissues per test substance together with negative and positive controls.

Details on study design:

The test is based on the experience that irritant chemicals show cytotoxic effects following short term
exposure to the stratum corneum of the epidermis. The test is designed to predict and classify the skin
irritation potential of a test substance by assessment of its effect on a three dimensional human
epidermis model (1-10).
The test consists of topical application of Bis-Tes (dried) on the skin tissue for 15 minutes. After
exposure the skin tissue is thoroughly rinsed to remove the test substance and transferred to fresh
medium. After a 42 hour incubation period, determination of the cytotoxic (irritancy) effect is
performed.
Cytotoxicity is expressed as the reduction of mitochondrial dehydrogenase activity measured by
formazan production from 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) at the
end of the treatment.

The test was performed on a total of 3 tissues per test substance together with negative and positive
controls. Twenty five µl of the undiluted test substance was added (with a pipette) into 12-well plates
on top of the skin tissues. Three tissues were treated with 25 µl PBS (negative control) and 3 tissues
with 25 µl 5% SDS (positive control) respectively. The positive control was re-spread after 7 minutes
contact time. After the exposure period of 15 minutes at room temperature, the tissues were washed
with phosphate buffered saline to remove residual test substance. After rinsing the cell culture inserts
were each dried carefully and moved to a new well on 2 ml pre-warmed maintenance medium until all
tissues were dosed and rinsed. Subsequently the skin tissues were incubated for 42 hours at 37°C.

After incubation, cell culture inserts were dried carefully to remove excess medium and were
transferred into a 12-wells plate prefilled with 2 ml MTT-medium (0.3 mg/ml). The tissues were
incubated for approximately 3 h at 37°C. After incubation the tissues were placed on blotting paper to
dry the tissues. Total biopsy was made by using a biopsy punch. Epidermis was separated from the
collagen matrix and both parts were placed in prelabeled microtubes and extracted with 500 µl
isopropanol. Tubes were stored refrigerated and protected from light for
68 hours. The amount of extracted formazan was determined spectrophotometrically at 570 nm in
duplicate with the TECAN Infinite® M200 Pro Plate Reader.
Cell viability was calculated for each tissue as a percentage of the mean of the negative control
tissues. Skin irritation potential of the test substance was classified according to remaining cell viability
following exposure of the test substance.

Results and discussion

In vitro

Results

Results 1

Remarks on result:

other:

Results 2

Irritation / corrosion parameter:

other: other: mean relative tissue viability

Value:

ca. 103

Remarks on result:

other:

Remarks:

Basis: mean. Time point: 15 mins. Remarks: expressed as % . (migrated information)

In vivo

Irritant / corrosive response data:

Bis-Tes (dried) is non-irritant in the in vitro skin irritation test under the experimental conditions described in this report.

Other effects:

Bis-Tes (dried) was checked for possible direct MTT reduction by adding the test substance to MTT
medium. Because no colour change was observed it was concluded that Bis-Tes (dried) did not
interact with MTT.

The positive control had a mean cell viability after 15 minutes exposure of 35%. The absolute mean
OD570 of the negative control tissues was within the laboratory historical control data range.
The standard deviation value of the percentage viability of three tissues treated
identically was less than 8%, indicating that the test system functioned properly.

Any other information on results incl. tables

Mean tissue viability in the in vitro skin irritation test with Bis-Tes (dried)(expressed as % of control)

negative control 100%

Bis-Tes (dried): 103%

Postive control 35%

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

It is concluded that this test is valid and that Bis-Tes (dried) is non-irritant in the in vitro skin
irritation test under the experimental conditions described in this report.

Executive summary:

In vitro skin irritation test with Bis-Tes (dried) using a human skin model.

This report describes the ability of Bis-Tes (dried) to induce skin irritation on a human three

dimensional epidermal model (EPISKIN Small Model (EPISKIN-SMTM)). The possible skin irritation

potential of Bis-Tes (dried) was tested through topical application for 15 minutes.

The study procedures described in this report were based on the most recent OECD and EC

guidelines.

Batch 209-3 of Bis-Tes (dried) was a pale yellow liquid. Bis-Tes (dried) was applied undiluted (25 µl)

directly on top of the skin tissue for 15 minutes. After a 42 hour post-incubation period, determination

of the cytotoxic (irritancy) effect was performed. Cytotoxicity is expressed as the reduction of

mitochondrial dehydrogenase activity measured by formazan production from MTT at the end of the

treatment.

Skin irritation is expressed as the remaining cell viability after exposure to the test substance. The

relative mean tissue viability obtained after 15 minutes treatment with Bis-Tes (dried) compared to the

negative control tissues was 103%. Since the mean relative tissue viability for Bis-Tes (dried) was

above 50% after 15 minutes treatment Bis-Tes (dried) is considered to be non-irritant.

The positive control had a mean cell viability of 35% after 15 minutes exposure. The absolute mean

OD570 (optical density at 570 nm) of the negative control tissues was within the laboratory historical

control data range. The standard deviation value of the percentage viability of three tissues treated

identically was less than 8%, indicating that the test system functioned properly.

Finally, it is concluded that this test is valid and that Bis-Tes (dried) is non-irritant in the in vitro skin

irritation test under the experimental conditions described in this report.