Cyclohexyldimethoxymethylsilane

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

30.06.1995 to 14.07.1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Cyclohexyldimethoxymethylsilane

EC Number:

402-140-1

EC Name:

Cyclohexyldimethoxymethylsilane

Cas Number:

17865-32-6

Molecular formula:

C9H20O2Si

IUPAC Name:

cyclohexyldimethoxymethylsilane

Test material form:

liquid

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: David Percival Ltd., UK
- Age at study initiation: 12-16 weeks
- Weight at study initiation: 2.38-2.89 kg
- Housing: Individually in suspended metal cages
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: Minimum of five days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18-24
- Humidity (%): 49-74
- Air changes (per hr): Approximately 15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 30.06.1995 To: 14.07.1995

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

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

Duration of treatment / exposure:

4 h

Observation period:

14 days (approximately 1, and 24, 48 and 72 hours, and 7 and 14 days after removal of patches)

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: Dorsal flank
- % coverage: No data
- Type of wrap if used: Semi-occlusive

REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes, residual test substance removed by gentle swabbing with cotton wool soaked in 74% Industrial methylated spirits
- Time after start of exposure: 4 hours

SCORING SYSTEM: Draize

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Remarks:

(mean score 1)

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 7-14 days

Remarks on result:

probability of moderate irritation

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Remarks:

(mean score 2)

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

probability of moderate irritation

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Remarks:

(mean score 3)

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

probability of moderate irritation

Results 4

Irritation parameter:

edema score

Basis:

animal #1

Remarks:

(mean score 1)

Time point:

24/48/72 h

Score:

3

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

probability of moderate irritation

Results 5

Irritation parameter:

edema score

Basis:

animal #2

Remarks:

(mean score 2)

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

probability of mild irritation

Results 6

Irritation parameter:

edema score

Basis:

animal #3

Remarks:

(mean score 3)

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

probability of mild irritation

Results 7

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: Sum of 24 and 72-hour reading

Score:

4.3

Max. score:

8

Reversibility:

fully reversible within: 7-14 days

Remarks on result:

probability of moderate irritation

Irritant / corrosive response data:

Well-defined erythema and slight to moderate oedema were noted at all treated skin sites one hour after patch removal and at the 24, 48 and 72-hour observations. The erythema extended up to 3 cm beyond one treatment site at the one hour observation and up to 6 cm beyond the remaining treatment sites at the 24, 48 and 72 hour observations.

Other effects:

Crust formation was noted at all treated skin sites at the 7-day observation. Crust formation prevented accurate evaluation of erythema at one treated skin site at this time. Desquamation was noted at all treated skin sites 14 days after treatment. This reaction was considered to be reversible.

Any other information on results incl. tables

Table 1 Summary of individual irritation scores

Skin reaction	Observation time	Scores
		Animal 1	Animal 2	Animal 3
Erythema	1 hour	2R	2	2
	24 hours	2R	2R	2
	48 hours	2R	2R	2
	72 hours	2R	2R	2
	7 days	?eCf	0Cf	0Cf
	14 days	0D	0D	0D
Oedema	1 hour	3	2	2
	24 hours	3	2	2
	48 hours	3	2	2
	72 hours	3	2	2
	7 days	0	0	0
	14 days	0	0	0

D= desquamation

R= reaction extending up to 3 to 6 cm beyond treatment site

Cf= crust formation

?e= adverse reactions prevent accurate evaluation of erythema

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

In an acute dermal irritation study conducted to OECD Test Guideline 404 and in compliance with GLP (reliability score 1) cyclohexyldimethoxymethylsilane was irritating to the skin of rabbits under semi-occlusive conditions, based on persistent, widespread erythema and oedema, with desquamation in all three animals. The irritation was reversible.