Dimethoxymethyloctadecylsilane

Endpoint summary

Description of key information

Skin irritation (OECD 404): not irritating
Eye irritation (OECD 405): not irritating 

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

Study period:

13 May - 13 Jun 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Freie und Hansestadt Hamburg, Behörde für Arbeit, Gesundheit uns Soziales, Germany

Species:

rabbit

Strain:

Himalayan

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: LPT, Laboratory of Pharmacology and Toxicology KG, Loehndorf, Germany
- Age at study initiation: approximately 4 months
- Weight at study initiation: 1.9-2.2 kg
- Fasting period before study: no
- Housing: Single housing before and after the exposure period. During exposure the animals were kept singly in restrainers, which allowed free movement of the head but prevented a complete body turn.
- Diet: ssniff K-H (ssniff Spezialdiäten GmbH, Soest, Germany), ad libitum
- Water: tap water, ad libitum
- Acclimation period: at least 20 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20±3
- Humidity (%): 55± 15
- Photoperiod (hrs dark / hrs light): 12/12

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

other: untreated skin site served as control

Amount / concentration applied:

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

Duration of treatment / exposure:

4 h

Observation period:

72 h
Reading time points: 24, 48 and 72 h

Number of animals:

3 males

Details on study design:

TEST SITE
- Area of exposure: approximately 6 cm²
- Type of wrap if used: Test site covered with a gauze patch, which was held in contact to the skin by means of a semi-occlusive dressing (non-irritating tape).

REMOVAL OF TEST SUBSTANCE
No residual test substance had to be removed

SCORING SYSTEM: Draize scoring system

Irritation parameter:

erythema score

Basis:

mean

Remarks:

out of all 3 animals

Time point:

other: mean over 24, 48, 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Irritation parameter:

edema score

Basis:

mean

Remarks:

out of all 3 animals

Time point:

other: mean over 24, 48, 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Irritant / corrosive response data:

No erythema and oedema reactions were observed 60 min after patch removal or at later time points in any animal. No other skin reactions were observed.

Other effects:

No systemic intolerance reactions were observed.

Interpretation of results:

other: CLP/EU GHS criteria are not met, no classification required according to Regulations (EC) No 1272/2008

Conclusions:

A reliable study performed in accordance with OECD 404 and GLP found the test material to be not irritating to the skin of rabbits. No erythema or oedema reactions were observed at any time point. No other skin reactions or systemic effects were observed.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

13 May - 16 Jun 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Freie und Hansestadt Hamburg, Behörde für Arbeit, Gesundheit uns Soziales, Germany

Species:

rabbit

Strain:

Himalayan

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: LPT, Laboratory of Pharmacology and Toxicology KG, Loehndorf, Germany
- Age at study initiation: approximately 4 months
- Weight at study initiation: 2.0-2.1 kg
- Fasting period before study: no
- Housing: Single housing before and after the exposure period. For 8 h following test substance application the animals were kept singly in restrainers, which allowed free movement of the head but prevented a complete body turn.
- Diet: ssniff K-H (ssniff Spezialdiäten GmbH, Soest, Germany), ad libitum
- Water: tap water, ad libitum
- Acclimation period: at least 20 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20±3
- Humidity (%): 55± 15

Vehicle:

unchanged (no vehicle)

Controls:

other: untreated left eye served as control

Amount / concentration applied:

TEST MATERIAL
- Amount applied (volume or weight with unit): 0.1 mL

Duration of treatment / exposure:

single application without rinsing

Observation period (in vivo):

72 h
Reading time points: 24, 48 abd 72 h

Number of animals or in vitro replicates:

3 males

Details on study design:

SCORING SYSTEM: Draize scoring system

TOOL USED TO ASSESS SCORE: hand-slit lamp / fluorescein

The test substance was placed in the conjunctival sac of the right eye of each animal after gently pulling the lower lid away from the eyeball. The lids were then gently held together for about one second in order to prevent loss of the material. The eyes were examined ophthalmoscopically with a slit lamp prior to the administration and 1, 24, 48, and 72 hours after the administration. 24 h after administration the eyes were treated additionally with fluorescein and examined.

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

other: mean after 24, 48, 72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 h

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

other: mean after 24, 48, 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

other: mean after 24, 48, 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Irritation parameter:

iris score

Basis:

mean

Remarks:

out of all 3 animals

Time point:

other: mean after 24, 48, 72 h

Score:

0

Max. score:

2

Reversibility:

other: not applicable

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

out of all 3 animals

Time point:

other: mean after 24, 48, 72 h

Score:

0

Max. score:

3

Reversibility:

other: not applicable

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

out of all 3 animals

Time point:

other: mean after 24, 48, 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Irritant / corrosive response data:

Corneal opacity was observed at 1 h in 1/3 animals (grade 1) and was fully reversible within 48 h. No effects on iris were observed in any animal at any time point. At 1 h redness and chemosis (grade 1) were observed in 3/3 animal. These effects were fully reversible within 24 h. After fluorescein staining after 24 h corneal staining was observed in 1/3 animals (1/4 of surface). No other effects were observed.

Other effects:

No systemic intolerance reactions were observed.

Table 1: Individual results of the eye irritation study in rabbits.

Rabbit #	Time [h]	conjunctivae		iris	cornea
		redness	swelling
1	1	1	1	0	1
	24	0	0	0	1
	48	0	0	0	0
	72	0	0	0	0
	average	0	0	0	0.33
2	1	1	1	0	0
	24	0	0	0	0
	48	0	0	0	0
	72	0	0	0	0
	average	0	0	0	0
3	1	1	1	0	0
	24	0	0	0	0
	48	0	0	0	0
	72	0	0	0	0
	average	0	0	0	0

Interpretation of results:

other: CLP/EU GHS criteria are not met, no classification required according to Regulations (EC) No 1272/2008

Conclusions:

A reliable study performed in accordance with OECD 405 and GLP found the test material to be not irritating to the eye of rabbits. Corneal opacity was observed at 1 h in 1/3 animals (grade 1) and was fully reversible within 48 h. No effects on iris were observed in any animal at any time point. At 1 h redness and chemosis (grade 1) were observed in 3/3 animal. These effects were fully reversible within 24 h. After fluorescein staining after 24 h corneal staining was observed in 1/3 animals (1/4 of surface). No other effects were observed. Mean values (over 24, 48, 72 h) for cornea score were 0.33, 0, and 0 in animal 1, 2, and 3, respectively. Mean values for redness, chemosis, and iris (over 24, 48, 72 h) were 0 in all animals.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

A skin irritation test is available with dimethoxymethyloctadecylsilane (CAS 70851-50-2), which was performed in Himalayan rabbits according to OECD 404 and in compliance with GLP (LPT, 2002). Pure test substance (0.5 mL) was applied to a 6 cm² application site (shaved) for 4 h under semi-occlusive conditions. No residual test substance had to be removed. Sixty minutes and 24, 48, 72 h after patch removal the application site was examined. No erythema and oedema reactions were observed 60 min after patch removal or at later time points in any animal. Thus, the mean values for erythema and oedema (over 24, 48, and 72 h) were 0. No other skin reactions were observed and no systemic effects were reported. In conclusion, dimethoxymethyloctadecylsilane was not irritating to the skin under the conditions of the test.

An eye irritation test is available with dimethoxymethyloctadecylsilane (CAS 70851-50-2), which was performed in Himalayan rabbits according to OECD 405 and in compliance with GLP (LPT, 2002). Pure test substance (0.1 mL) was placed in the conjunctival sac of the right eye of each animal after gently pulling the lower lid away from the eyeball. The lids were then gently held together for about one second in order to prevent loss of the material. The eyes were examined ophthalmoscopically with a slit lamp prior to the administration and 1, 24, 48, and 72 hours after the administration. 24 h after administration the eyes were treated additionally with fluorescein and examined. Corneal opacity was observed at 1 h in 1/3 animals (grade 1) and was fully reversible within 48 h. No effects on iris were observed in any animal at any time point. At 1 h redness and chemosis (grade 1) were observed in 3/3 animal. These effects were fully reversible within 24 h. Mean values (over 24, 48, 72 h) for cornea score were 0.33, 0, and 0 in animal 1, 2, and 3, respectively. Mean values for redness, chemosis, and iris (over 24, 48, 72 h) were 0 in all animals. After fluorescein staining after 24 h corneal staining was observed in 1/3 animals (1/4 of surface). No other local or systemic effects were observed.

In conclusion, dimethoxymethyloctadecylsilanewas not irritating to the eye under the conditions of the test.

Justification for classification or non-classification

The available data on skin irritation/corrosion and eye irritation of the registered substance do not meet the criteria for classification according to Regulation (EC) 1272/2008 and according to Directive 67/548/EEC, and are therefore conclusive but not sufficient for classification.