Dichlorosilane

Endpoint summary

Description of key information

The key study for skin irritation (BRRC, 1982) found dichlorosilane to be corrosive to skin.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

no

Specific details on test material used for the study:

The test material was a gas at room temperature and it was converted to liquid state before dosing. The equipment for this procedure was provided by the sponsor.

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

No details given.

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5ml
- Concentration: 100%

Duration of treatment / exposure:

4 hours

Observation period:

7 days

Number of animals:

6

Details on study design:

TEST SITE
- Area of exposure: not stated
- % coverage: not stated
- Type of wrap if used: gauze patch loosely covered with impervious sheeting

REMOVAL OF TEST SUBSTANCE
- Washing: not stated

SKIN REACTION: recorded at 1 hour, 24, 48, 72 hours and 7 days after dosing
SCORING SYSTEM: not stated

Irritation parameter:

other: necrosis

Basis:

other: all animals

Time point:

other: 1 hour

Reversibility:

not reversible

Remarks on result:

other: necrosis recorded for all animals

Irritation parameter:

other:

Basis:

other: all animals

Time point:

other: 24, 48, 72 hours and 7 days

Reversibility:

not reversible

Remarks on result:

other: necrosis, scab formation and ulceration recorded

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Remarks:

necrosis and scab formation observed

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Remarks:

necrosis and scab formation observed. Ulciration also observed from 48h to day 7.

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Remarks:

necrosis and scab formation observed

Irritation parameter:

erythema score

Basis:

animal #4

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Remarks:

necrosis and scab formation observed

Irritation parameter:

erythema score

Basis:

animal #5

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Remarks:

necrosis, ulciration and scab formation observed

Irritation parameter:

erythema score

Basis:

animal #6

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Remarks:

necrosis and scab formation observed

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Irritation parameter:

edema score

Basis:

animal #4

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Irritation parameter:

edema score

Basis:

animal #5

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Irritation parameter:

edema score

Basis:

animal #6

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Irritant / corrosive response data:

Severe necrosis recorded for all 6 rabbits with 5 hours of the start of the contact period. Three rabbits had visible areas of necrosis within 15 minutes. Scabs appeared after 24 hours and ulceration was noted in 2 rabbits after 48 hours. Severe reactions were noted up to 7 days.

Other effects:

None stated

Interpretation of results:

Category 1 (corrosive) based on GHS criteria

Conclusions:

Application of dichlorosilane to rabbit skin resulted in severe necrosis from 15 minutes after the 4 hour exposure period, scabs and ulceration were also noted and effects were recorded for up to 7 days. Based on this study dichlorosilane was considered to be corrosive to skin.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (corrosive)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vitro / ex vivo

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study need not be conducted because the available information indicates that the criteria are met for classification as corrosive to the skin or irritating to eyes

Endpoint conclusion

Endpoint conclusion:

no study available

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Additional information

The key study for skin irritation (BRRC, 1982) tested liquefied dichlorosilane and found it to be corrosive to the skin of rabbits. The study was conducted according to a protocol comparable to current guideline but not compliant with GLP. Necrosis, scab formation and ulceration were noted up to 7 days after application.

Although there was no specific study to investigate respiratory irritation, pathology examination in the repeat dose studies (Dodd, 1990 and Nakashima, 1996) showed signs of respiratory irritation.

Justification for classification or non-classification

Based on the available data dichlorosilane requires classification Skin Corrosive 1A and Eye Damage 1, H314: Causes severe skin burns and eye damage, according to Regulation (EC) No 1272/2008. This is based on the skin irritation/corrosion data that shows the test substance is clearly corrosive to the skin. It is assumed that substances that are corrosive to the skin are also damaging to the eyes, so there is no separate labelling for the eyes. There are no specific data for respiratory irritation, however, the pathology examination in the repeat dose inhalation studies revealed signs of respiratory irritation. Therefore, the hazard statement 'EUH071 Corrosive to the respiratory tract' is applied.