Tris(2-methoxyethoxy)vinylsilane

Endpoint summary

Description of key information

In a skin sensitisation study (Buehler Test), conducted according to OECD Test Guideline 406 and in compliance with GLP, tris(2-methoxyethoxy)vinylsilane was not sensitising to the skin of guinea-pigs (Harlan Laboratories, 2010).

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20.04.2010 to 27.05.2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

Buehler test

Justification for non-LLNA method:

An LLNA study was not performed because the test method is not considered to be suitable for substances that contain silicon. Please refer to the attached document for further details.

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

male

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories B.V.
- Age at study initiation: 8-10 weeks
- Weight at study initiation: 567-738 grams
- Housing: Individually in Makrolon Type 4 cages
- Diet: Ad libitum
- Water: Ad libitum
- Acclimation period: Six days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 3 °C
- Humidity (%): 30-70 %
- Air changes (per hr): 10-15 / hour
- Photoperiod (hrs dark / hrs light): 12 hours dark / 12 hours light

IN-LIFE DATES: From: 20.04.2010 To: 27.05.2010

Route:

epicutaneous, occlusive

Vehicle:

other: Diglyme

Concentration / amount:

100% for induction and 1% for challenge

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

other: Diglyme

Concentration / amount:

100% for induction and 1% for challenge

No. of animals per dose:

Three for irritation screen forinduction, challenge I and II, 10 for control group, 20 for test group.

Details on study design:

RANGE FINDING TESTS: The test item concentration used in the epidermal induction should be a concentration producing some irritation but not adversely affected the animals. During the irritation screen, the test item at 100% (as delivered) as well as the test item formulated at 75% and 50% in diglyme produced discrete/patchy erythema in most of the three irritation screen animals. A discrete/patchy erythema appeared only in one out of three animals after treatment with the test item at 25% in diglyme. Therefore, the test item concentration of 100% was considered to be suitable for the 3-week induction. The concentration used in the epidermal challenge was the maximum tested non-irritant concentration. In this study 1% was the highest tested non-irritant concentration suitable for challenge.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: Three
- Exposure period: Six hours
- Test groups: 100 % test substance only
- Control group: Negative control of Diglyme
- Site: Left shoulder
- Frequency of applications: Every seven days (Test days 1, 8 and 15)
- Concentrations: 100%

B. CHALLENGE EXPOSURE
- No. of exposures: One
- Day(s) of challenge: Day 29
- Exposure period: Six hours
- Test groups: treated with 1% test substance
- Control group: treated with 1% test substance
- Site: Left posterior quadrant
- Concentrations: 1%
- Evaluation (hr after challenge): The grading method used for irritation screen, induction and challenge was identical. It was performed 24 ± 2 hours after removal of the patches for irritation screen, induction and challenge and repeated 24 ± 2 hours later (48-hour grades) for the irritation screen and the challenge.

OTHER: Viability/mortality was checked daily until termination of the test. Clinical signs and grading of skin response were recorded daily from delivery to termination of the test. Skin responses were graded during the irritation screens, induction and challenge periods. Body weights were recorded at delivery/acclimitisation start, at the end of the irritation screen, at test day 1 (day of treatment) and at the termination of the study.

Challenge controls:

Diglyme only

Positive control substance(s):

yes

Positive control results:

Nine and six of twenty test animals were observed with discrete/patchy erythema at the 24- and 48-hour readings, respectively, after the challenge treatment with the highest tested non-irritating concentration of alph-hexylcinnamaldehyde at 5% in PEG 300. No skin effect was observed in the control group.

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

Diglyme only

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

None

Remarks on result:

no indication of skin sensitisation

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

Diglyme only

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

None

Remarks on result:

no indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

1%

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

None

Remarks on result:

no indication of skin sensitisation

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

1%

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

None

Remarks on result:

no indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

24

Group:

positive control

Dose level:

5%

No. with + reactions:

9

Total no. in group:

20

Remarks on result:

positive indication of skin sensitisation

Reading:

2nd reading

Hours after challenge:

48

Group:

positive control

Dose level:

5%

No. with + reactions:

6

Total no. in group:

20

Remarks on result:

positive indication of skin sensitisation

There were no deaths or clinical signs of systemic toxicity in any animal. Body weights were unaffected by treatment.

In the test group treated with the test item at 100% (used as delivered), discrete/patchy erythema (grade 1) was observed in all 20 test animals during the first and second induction and in 3 out of 20 animals in the third induction. Discrete/patchy erythema (grade 1) was observed in one out of 10 control animals (10%) and in one out of 20 test animals (5%) after treatment with the test item at 1% in Diglyme. Therefore, none of the reactions in the challenge phase were greater than those in the induction phase.

Interpretation of results:

GHS criteria not met

Conclusions:

In a skin sensitisation study (Buehler Test), conducted according to OECD test guideline 406 and in compliance with GLP (reliability score 1), tris(2-methoxyethoxy)vinylsilane was not sensitising to the skin of guinea-pigs.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

A sensitisation study using tris(2-methoxyethoxy)vinylsilane, conducted according to OECD Test Guideline 406 and in compliance with GLP, found the test material to not be sensitising (Harlan Laboratories, 2010). There were no deaths or clinical signs of systemic toxicity in any animal. Body weights were unaffected by treatment.

In the test group treated with the test item at 100% , discrete/patchy erythema (grade 1) was observed in all 20 test animals during the first and second induction and in 3 out of 20 animals in the third induction. Discrete/patchy erythema was observed in one out of 10 control animals (10%) and in one out of 20 test animals after treatment with the test item at 1% in diglyme. None of the reactions in the challenge phase were deemed greater than those in the induction phase.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Based on the available data tris(2-methoxyethoxy)vinylsilane does not require classification for sensitisation according to Regulation (EC) No 1272/2008.

There are no data to suggest that the substance should be classified as a respiratory sensitiser.