tert-butylchlorodimethylsilane

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

7 June to 22 June 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2500 (Acute Dermal Irritation)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

018162-48-6

Cas Number:

018162-48-6

IUPAC Name:

018162-48-6

Constituent 2

Reference substance name:

tert-butylchlorodimethylsilane

EC Number:

242-042-4

EC Name:

tert-butylchlorodimethylsilane

Cas Number:

18162-48-6

Molecular formula:

C6H15ClSi

IUPAC Name:

tert-butyl(chloro)dimethylsilane

Test material form:

solid: crystalline

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Winkelmann GmbH, Germany
- Age at study initiation: not stated
- Weight at study initiation: 3.4 kg
- Housing: ABS plastic rabbit cages
- Diet (ad libitum): Altromin 2123 rabbit maintenance diet
- Water (ad libitum): tap water
- Acclimation period: stated as "adequate"

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18+/- 3
- Humidity (%): 45-65
- Air changes (per hr): at least 10
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 7 June 2005 To: 22 June 2005

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

physiological saline

Controls:

other: untreated side of same animal

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5g

Duration of treatment / exposure:

4 hours

Observation period:

14 days

Number of animals:

1 female

Details on study design:

TEST SITE
- Area of exposure: approximately 6 cm2
- Type of wrap if used: gauze patch held in place with non-irritating tape, patch was fixed with semi-occlusive dressing

REMOVAL OF TEST SUBSTANCE
- Washing: not stated
- Time after start of exposure: 4 hours

SCORING SYSTEM: according to guideline

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: 0 hours

Score:

0

Max. score:

4

Results 2

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: 1 hour

Score:

0

Max. score:

4

Results 3

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24 h

Score:

2

Max. score:

4

Reversibility:

not reversible

Results 4

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

48 h

Score:

1

Max. score:

4

Reversibility:

not reversible

Results 5

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

72 h

Score:

1

Max. score:

4

Reversibility:

not reversible

Results 6

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: Day 2 to Day 12

Score:

1

Max. score:

4

Reversibility:

not reversible

Results 7

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: Day 13 to 14

Score:

1

Max. score:

4

Reversibility:

not reversible

Results 8

Irritation parameter:

edema score

Basis:

animal #1

Time point:

other: 0 hours

Score:

0

Max. score:

4

Results 9

Irritation parameter:

edema score

Basis:

animal #1

Time point:

other: 1 hour

Score:

0

Max. score:

4

Results 10

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24 h

Score:

2

Max. score:

4

Reversibility:

not reversible

Results 11

Irritation parameter:

edema score

Basis:

animal #1

Time point:

48 h

Score:

1

Max. score:

4

Reversibility:

not reversible

Results 12

Irritation parameter:

edema score

Basis:

animal #1

Time point:

72 h

Score:

1

Max. score:

4

Reversibility:

not reversible

Results 13

Irritation parameter:

edema score

Basis:

animal #1

Time point:

other: Day 2 to 12

Score:

1

Max. score:

4

Reversibility:

not reversible

Results 14

Irritation parameter:

edema score

Basis:

animal #1

Time point:

other: Day 13 to 14

Score:

1

Max. score:

4

Reversibility:

not reversible

Irritant / corrosive response data:

After patch removal the application site showed necrotic skin over the whole application area. Necrotic tissue covered the application area for 12 days showing erythema grade 2 and edema grade 2 at the edge of the application area the first day after application. Erythema and edema at the edge of the application area decreased to grade 1 on Day 2 and continued at grade 1 until the end of the study. The necrotic tissue dropped off the application area on Day 13, showing an open wound, only covered with a gauzy dry film, at the edges the skin was dry and necrotic. Similar observations were recorded on Day 14. No further animals were treated.

Other effects:

Slight weight loss, approximately 6%, was noted during the 14 day observation period.

Applicant's summary and conclusion

Interpretation of results:

Category 1A (corrosive) based on GHS criteria

Conclusions:

Tert-butyl(chloro)dimethylsilane causes severe corrosive effects to rabbit skin.