Silicic acid, ethyl ester

Endpoint summary

Description of key information

uehler test was performed to assess the dermal sensitization potential of the test chemical. The study was performed according to OECD 406 Guidelines.

In the test chemical treated animals, very light erythema and edema was observed in 2 of 10 treated animals during Induction Phase I, and in 3 of 10 animals in Induction Phase II; no skin irritation was observed in the control animals. Skin irritation was not observed in the control or test chemical-treated animals in Induction Phase III or at challenge. 

Hence, the test chemical was considered to be not sensitizing to skin.

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:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Justification for type of information:

Data is from secondary source.

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Principles of method if other than guideline:

Buehler test was performed to assess the dermal sensitization potential of the test chemical

GLP compliance:

not specified

Type of study:

Buehler test

Justification for non-LLNA method:

not specified

Species:

guinea pig

Strain:

not specified

Sex:

not specified

Details on test animals and environmental conditions:

No data available.

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Concentration / amount:

iNDUCTION I- undiluted
INDUCTION II- undiluted
INDUCTION III- undiluted

Day(s)/duration:

No data available

Adequacy of induction:

not specified

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

other: MEH 56 corn oil

Concentration / amount:

50% test chemical in MEH 56 corn oil

Day(s)/duration:

No data available

Adequacy of challenge:

not specified

No. of animals per dose:

Total:30
Test group:20
control :10

Details on study design:

Details on study design
RANGE FINDING TESTS: Pretests were conducted to determine the dose levels used in induction and challenge.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 3
- Exposure period: No data available
- Test groups:20
- Control group:10
- Site: No data available
- Frequency of applications: No data available
- Duration: No data available
- Concentrations: undiluted

B. CHALLENGE EXPOSURE
- No. of exposures: one
- Day(s) of challenge: No data available
- Exposure period: No data available
- Test groups:20
- Control group:10
- Site: No data available
- Concentrations: 50% test chemical in MEH 56 corn oil
- Evaluation (hr after challenge):

Challenge controls:

Yes

Positive control substance(s):

not specified

Key result

Reading:

other: Challenge

Group:

test chemical

Dose level:

50% test chemical in MEH 56 corn oi

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

Skin irritation was not observed in the control or test chemical-treated animals in Induction Phase III or at challenge. 

Remarks on result:

no indication of skin sensitisation

Interpretation of results:

other: Not sensitizing

Conclusions:

In the test chemical treated animals, very light erythema and edema was observed in 2 of 10 treated animals during Induction Phase I, and in 3 of 10 animals in Induction Phase II; no skin irritation was observed in the control animals. Skin irritation was not observed in the control or test chemical-treated animals in Induction Phase III or at challenge. 
Hence, the test chemical was considered to be not sensitizing to skin.

Executive summary:

Buehler test was performed to assess the dermal sensitization potential of the test chemical. The study was performed according to OECD 406 Guidelines.Pretests were conducted to determine the dose levels used in induction and challenge. A group of guinea pigs (strain not specified; 10 control animals and 20 treated animals in each study) were induced twice with undiluted occlusive epicutaneous exposures to the test chemical. They were induced for the third time, and challenged, with an occlusive epicutaneous exposure to 50% test chemical in MEH 56 corn oil.

In the test chemical treated animals, very light erythema and edema was observed in 2 of 10 treated animals during Induction Phase I, and in 3 of 10 animals in Induction Phase II; no skin irritation was observed in the control animals. Skin irritation was not observed in the control or test chemical-treated animals in Induction Phase III or at challenge. 

Hence, the test chemical was considered to be not sensitizing to skin.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Various studies have been reviewed to determine the skin sensitization potential of the test chemical in living organisms. These include in vivo experimental studies performed on Guinea pigs for the test chemical.

Buehler test was performed to assess the dermal sensitization potential of the test chemical. The study was performed according to OECD 406 Guidelines. Pretests were conducted to determine the dose levels used in induction and challenge. A group of guinea pigs (strain not specified; 10 control animals and 20 treated animals in each study) were induced twice with undiluted occlusive epicutaneous exposures to the test chemical. They were induced for the third time, and challenged, with an occlusive epicutaneous exposure to 50% test chemical in MEH 56 corn oil.

In the test chemical treated animals, very light erythema and edema was observed in 2 of 10 treated animals during Induction Phase I, and in 3 of 10 animals in Induction Phase II; no skin irritation was observed in the control animals. Skin irritation was not observed in the control or test chemical-treated animals in Induction Phase III or at challenge. 

Hence, the test chemical was considered to be not sensitizing to skin.

This is supported by the results of another Buehler test performed in guinea pigs to evaluate the sensitization potential of the test chemical. The study was performed according to OECD 406 Guidelines. Pretests were conducted to determine the dose levels used in induction and challenge.

30 guinea pigs were used for the study. 3 induction exposures were carried out as follows-

1^stinduction- undiluted occlusive epicutaneous

2nd Induction- undiluted occlusive epicutaneous

3rd Induction- undiluted

After the third induction phase, the test animals were rested for a suitable period, and later subjected to challenge exposure using undiluted test chemical under occlusive conditions.

There were no substance related effects or influence on body weight in either test or control animals. There was no skin irritation observed in either test or control animals in Induction Phase III, I, II or in the Challenge Phase.

Hence, the test chemical was considered to be not sensitizing to skin.

Based on the available results and applying the weight of evidence approach, the test chemical can be considered to be not sensitizing to skin. Comparing the above annotations with the criteria of CLP Regulations, the test chemical can be classified under the category “Not Classified”.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Based on the available results and applying the weight of evidence approach, the test chemical can be considered to be not sensitizing to skin. Comparing the above annotations with the criteria of CLP Regulations, the test chemical can be classified under the category “Not Classified”.