N,N',N''-tricyclohexyl-1-methylsilanetriamine

Endpoint summary

Description of key information

In the key study for skin irritation, N,N',N''-tricyclohexyl-1-methylsilanetriamine is reported to be corrosive following a 3 minute exposure period, based on the criteria of EEC 84/449 Annex V Method B4 (Hazleton, 1990). The supporting study reported the substance to be corrosive following a 4 hour exposure period, based on reported destruction of the skin tissue described as third degree chemical burns (SWS Silicones Corporation, 1976).  

In accordance with Column 2 of REACH Annex VIII, the in vivo eye irritation study (required in Section 8.2.1) does not need to be conducted as the substance is classified as 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:

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

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, France
- Age at study initiation: adult
- Weight at study initiation: 250-270 g
- Housing: individually in polystyrene cages
- Diet: 150 g per animal per day of complete pelleted rabbit maintenance diet
- Water: softened and filtered mains drinking water, ad libitum
- Acclimation period: 15 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-23
- Humidity (%): 38-75
- Photoperiod (hrs dark / hrs light): 12/12

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.5 ml

Duration of treatment / exposure:

3 minutes

Observation period:

Cutaneous examinations were performed at 1, 24, 48 and 72 hours post-treatment.

Number of animals:

6 rabbits

Details on study design:

TEST SITE
- Area of exposure: back and flanks
- % coverage: 14 cm x 14 cm
- Type of wrap if used: The test article and the gauze square were held in contact with the skin by mean of semi-occlusive dressing: perforated adhesive tape applied onto a band of crepe gauze.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no washing
- Time after start of exposure: 3 minutes

SCORING SYSTEM: Draize

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: Corrosive

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: Corrosive

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: Corrosive

Irritation parameter:

erythema score

Basis:

animal #4

Time point:

24/48/72 h

Score:

2.7

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: Corrosive

Irritation parameter:

erythema score

Basis:

animal #5

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: Corrosive

Irritation parameter:

erythema score

Basis:

animal #6

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: Corrosive

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

not reversible

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1.3

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

edema score

Basis:

animal #4

Time point:

24/48/72 h

Score:

1.3

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

edema score

Basis:

animal #5

Time point:

24/48/72 h

Score:

1.3

Max. score:

4

Reversibility:

fully reversible within: 7 days

Irritation parameter:

edema score

Basis:

animal #6

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible

Irritant / corrosive response data:

Well defined erythema was observed in 5 out of 6 animals at 1 hour after removal of the test material. One animal had slight erythema.
Burnt aspect of the exposure area was observed at 24 hours in 5 out of 6 animals. One animal had well defined erythema.
Burnt aspects and dryness of the exposure area was evident at 48 and 72 hours post-treatment in 4 out of 6 animals. One animal exhibited only burnt aspect and another well defined erythema.

Other effects:

One animal was found dead before the end of the 14-day study period. Reversability of the corrosive effects were not confirmed.

Interpretation of results:

Category 1A (corrosive) based on GHS criteria

Conclusions:

Based on the available information from the key skin irritation/corrosion study for N,N',N''-tricyclohexyl-1-methylsilanetriamine, the test material is reported 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:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

In the key study for skin irritation, N,N',N''-tricyclohexyl-1-methylsilanetriamine is reported to be corrosive following a 3 minute exposure period, based on the criteria of EEC 84/449 Annex V Method B4 (Hazleton, 1990).

Following a 3 minute application of the test material onto the intact skin of six rabbits, the study authors reported erythema scores of 3.33 at 24 hours, 3.67 at 72 hours, 3.5 on day 7 and 2.2 on day 14. Oedema was also observed in all the animals. The study reports necrosis followed by eschar formation in two of the rabbits (day 7). One of these two test animals died of diarrhoea before the end of the study. What are described as "burnt aspect" is described for in three of the other animals on day seven and in three out of five surviving animals on day 14.

The supporting study reported the substance to be corrosive following a 4 hour exposure period, based on reported destruction of the skin tissue described as third degree chemical burns (SWS Silicones Corporation, 1976). Following 4-hour application of the test material onto a rabbit skin, the study authors report the primary irritation score for the test material to be 8 (the maximum score), indicating third degree chemical burns. Erythema and oedema were observed in all the animals with the maximum reaction score of 4. Necrosis and eschar were also observed in all the animals.

In accordance with Column 2 of REACH Annex VIII, the in vitro eye irritation study (required in Section 8.2.1) does not need to be conducted as the substance is classified as corrosive to skin.

Justification for classification or non-classification

Based on the available data, N,N',N''-tricyclohexyl-1-methylsilanetriamine is classified as Corrosive to Skin Category 1A, 'H314; Causes severe skin burns and eye damage' according to Regulation (EC) No 1272/2008.