Silanediol, 1-methyl-1-(1-methylethoxy)-, 1,1-diacetate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15 May - 24 Jul 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

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

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

442-070-9

EC Name:

-

Cas Number:

329039-38-5

Molecular formula:

Hill formula: C8 H16 O5 Si CAS formula: C8 H16 O5 Si

IUPAC Name:

(acetyloxy)(methyl)(propan-2-yloxy)silyl acetate

Details on test material:

- Name of test material (as cited in study report): Methyldiacetoxyisopropoxy Silane
- Physical state: Clear, colorless liquid
- Analytical purity: 85.8 %
- Impurities (identity and concentrations): 12.9 % Acetoxydiisopropoxymethtylsilane, 1.3 % hydrolisis product (siloxane)
- Purity test date: 04.10.2001
- Lot/batch No.: AA001 (04/10/01)
- Stability under test conditions: Hydrolyzes to form poly(silicone); store under Nitrogen
- Storage condition of test material: Use ground strap and store under nitrogen in original container below 30 °C (85 °F) in hood.

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Millbrook Breeding Labs, Amherst, MA, USA
- Age at study initiation: 10 weeks
- Weight at study initiation: 2.13 - 2.22 kg
- Housing: Individual housing (suspended stainless-steel cages), bedding in hardwood chips (non-contact), Prochip, Harlan Teklad, Madison, WI
- Diet: TEK 8630 Rabbit Diet, Harlan Teklad, Madison, WI, ad libitum
- Water: Tap water, ad libitum
- Acclimation period: Minimum 5 days, under the same conditions as for the actual test

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 ± 3
- Humidity (%): 30 - 70
- Air changes (per hr): 10 - 15
- Photoperiod (hrs dark / hrs light): 12/12, full spectrum fluorescent lights

Test system

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped

Vehicle:

unchanged (no vehicle)

Controls:

other: untreated sites of the same animal served as control.

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL

Duration of treatment / exposure:

4 hours

Observation period:

72 hours
Reading time points: 1, 24, 48 and 72 hours

Number of animals:

2 males and 1 female

Details on study design:

TEST SITE
- Area of exposure: 6 cm²
- % coverage: 10
- Type of wrap if used: This gauze patch was applied to the intact skin of the clipped area. The patch was covered with a semi-occlusive dressing. The dressing was held in place with non-irritating tape

SCORING SYSTEM: Draize scoring system

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: mean over 24, 48 and 72 h

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

other: mean over 24, 48 and 72 h

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

other: mean over 24, 48 and 72 h

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Results 4

Irritation parameter:

edema score

Basis:

mean

Remarks:

out of all 3 animals

Time point:

other: mean over 24, 48 and 72 h

Score:

0

Max. score:

4

Reversibility:

other: reversibility: not applicable

Irritant / corrosive response data:

Very slight to well-defined erythema was observed in all 3 animals at 1-, 24- and 48-hour readings. The erytema was fully reversible in all animals at the 72-hour reading time point. The individual mean score for edema for each of the three animals was 0 at all readings.

Any other information on results incl. tables

Table 1: Skin irritation scores - individual values

Observation time	Rabbit no.
	1		2		3
	Erythema	Edema	Erythema	Edema	Erythema	Edema
1 h	1	0	1	0	2	0
24 h	1	0	1	0	1	0
48 h	1	0	1	0	1	0
72 h	0	0	0	0	0	0
Mean value 24 + 48 + 72 h	0.67	0.0	0.67	0.0	0.67	0.0

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

CLP: not classified
DSD: not classified

Executive summary:

The primary skin irritation potential of methyldiacetoxyisopropoxy silane was investigated by topical semi-occlusive application of 0.5 mL to the intact left flank of each of three young adult New Zealand White rabbits according to OECD TG 404. The test item showed slight erythema at the application site of any animal at the 24- and 48-hour time point readings. All skin reactions were fully reversible within 72 hours. Thus, methyldiacetoxyisopropoxy silane is considered to be “not irritating” to rabbit skin.