Registration Dossier

Administrative data

Description of key information

There are no skin or eye irritating data for the registered substance, 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane Vi4-D4. Therefore, data for the structural analogue, octamethyltetroxatetrasiloxane (D4, CAS 556-67-2) have been read across for these endpoints. Furthermore, read across data from decamethylcyclopentasiloxane (D5, CAS 541-02-6) and hexamethylcyclotrisiloxane (D3, CAS 541-05-9) for the impurities 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinylcyclopentasiloxane Vi5-D5 (CAS 17704-22-2; Impurity 1) and 2,4,6-trimethyl-2,4,6-trivinylcyclotrisiloxane Vi3-D3 (CAS 3901-77-7; Impurity 2) have been included as supporting information where available.

The key skin irritation study for D4, conducted according to а protocol similar to OECD Test Guideline 404 but prior to GLP, reports no irritation to the skin of rabbits and the test substance was concluded to be not irritating to skin (Laboratoires de Recherches de la Societe des Usines Chimiques RHONE POULENC, 1971).  

The key eye irritation for D4, conducted according to OECD Test Guideline 405 and in compliance with GLP, reports no irritant effects in rabbit eye and the substance was concluded to be not irritating to eyes (Dow Corning Corporation, 1997).  

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:
1971
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Remarks:
The study report lacked many details regarding the test animals and environmental conditions.
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
GLP compliance:
no
Species:
rabbit
Strain:
other: albino
Details on test animals or test system and environmental conditions:
TEST ANIMALS

- Source: Not stated

- Age at study initiation: Not stated

- Weight at study initiation: 2.3 - 2.8 kg

- Housing: Not stated

- Diet (e.g. ad libitum): Not stated

- Water (e.g. ad libitum): Not stated

- Acclimation period: Not stated

ENVIRONMENTAL CONDITIONS

- Temperature (°C): Not stated

- Humidity (%): Not stated

- Air changes (per hr): Not stated

- Photoperiod (hrs dark / hrs light): Not stated
Type of coverage:
not specified
Preparation of test site:
shaved
Vehicle:
unchanged (no vehicle)
Controls:
no
Amount / concentration applied:
TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 ml to intact and abraded skin

Duration of treatment / exposure:
24 hours
Observation period:
72 hours
Number of animals:
6
Details on study design:
TEST SITE

- Area of exposure: 4cm diameter


SCORING SYSTEM: Draize
Irritation parameter:
erythema score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
edema score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
erythema score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
edema score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
erythema score
Basis:
animal #3
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
edema score
Basis:
animal #3
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
erythema score
Basis:
animal #4
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
edema score
Basis:
animal #4
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
erythema score
Basis:
animal #5
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
edema score
Basis:
animal #5
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
erythema score
Basis:
animal #6
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
edema score
Basis:
animal #6
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Other effects:
No data

No skin reactions were observed at any time for intact skin. For abraded skin, desquamation was observed but was fully resolved after 72 hours.

Interpretation of results:
GHS criteria not met
Conclusions:
In a study that pre-dates GLP but was similar to OECD 404, D4 produced no skin reactions in rabbits. It is therefore not irritant according to EU criteria.
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:
1995/08/21 - 1997/09/30
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
GLP compliance:
yes
Species:
rabbit
Strain:
New Zealand White
Vehicle:
unchanged (no vehicle)
Controls:
other: Untreated eye
Duration of treatment / exposure:
24 hours
Observation period (in vivo):
72 hours
Number of animals or in vitro replicates:
3F
Irritation parameter:
cornea opacity score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
cornea opacity score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
cornea opacity score
Basis:
animal #3
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
iris score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0
Max. score:
2
Remarks on result:
no indication of irritation
Irritation parameter:
iris score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0
Max. score:
2
Remarks on result:
no indication of irritation
Irritation parameter:
iris score
Basis:
animal #3
Time point:
24/48/72 h
Score:
0
Max. score:
2
Remarks on result:
no indication of irritation
Irritation parameter:
chemosis score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
chemosis score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
chemosis score
Basis:
animal #3
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
conjunctivae score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0.3
Max. score:
3
Remarks on result:
other: Mean scores ranged from 0 to 0.3
Irritation parameter:
conjunctivae score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0.3
Max. score:
3
Remarks on result:
other: Mean scores ranged from 0 to 0.3
Irritation parameter:
conjunctivae score
Basis:
animal #3
Time point:
24/48/72 h
Score:
0.3
Max. score:
3
Remarks on result:
other: Mean scores ranged from 0 to 0.3
Irritation parameter:
maximum mean total score (MMTS)
Basis:
mean
Time point:
other: 1h
Score:
5.3
Other effects:
No deaths occurred during the study.
Interpretation of results:
GHS criteria not met
Conclusions:
The test material was determined not irritating in a reliable study conducted according to an appropriate test protocol, and in compliance with GLP.
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

There are no skin or eye irritating data for the registered substance, 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane Vi4-D4. Therefore, data for the structural analogue, octamethyltetroxatetrasiloxane (D4, CAS 556-67-2) have been read across for these endpoints.

The key skin irritation study for D4 was conducted according to a study protocol comparable to the appropriate OECD Test Guideline 404 but prior to GLP. In the study, 0.5 ml of undiluted test substance was applied to intact and abraded skin of rabbits, for 24 hours (type of coverage not reported). No irritant effects were reported (Laboratoires de Recherches de la Societe des Usines Chimiques RHONE POULENC, 1971). The test substance was concluded to be not irritating to skin.

The key eye irritation study for D4 was conducted according to OECD Test Guideline 405 and in compliance with GLP (Dow Corning Corporation, 1997). A single instillation of 0.1 ml of undiluted D4 was administrated into the right eye of each of three New Zealand white rabbits. The eyes were rinsed with lukewarm water 24 hours after instillation, and were then scored for irritation at 1, 24, 48 and 72 hours following test substance administration. D4 was determined not irritating to eyes under the conditions of this study.

IMPURITY PROFILE

The registration substance has an average purity of >80% Vi4-D4, with <15% 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinylcyclopentasiloxane Vi5-D5 (CAS 17704-22-2; Impurity 1) and <10% 2,4,6-trimethyl-2,4,6-trivinylcyclotrisiloxane Vi3-D3 (CAS 3901-77-7; Impurity 2) present as impurities. After due consideration of the properties, the presence of these impurities is not expected to affect the overall hazard profile of the substance. Read-across studies are in place as supporting studies, to consider the properties of the impurities. Data for Vi5-D5 are read-across from D5 (CAS 541-02-6), data for Vi3-D3 are read-across from D3 (CAS 541-05-9).

Read across from D5 (CAS 541-02-6) [SOURCE SUBSTANCE FOR IMPURITY 1]

For D5, the key skin irritation study (Toxicon Corporation, 1990b), conducted according to a guideline comparable to OECD Test Guideline 404 and in compliance with GLP, concluded the test material to be not irritating to skin.

For D5, the key eye irritation study (Toxicon Corporation, 1990c), conducted according to a guideline comparable to OECD Test Guideline 405 and in compliance with GLP, concluded the test material to be not irritating to eyes.

Read across from D3 (CAS 541-05-9) [SOURCE SUBSTANCE FOR IMPURITY 2]

There are no skin or eye irritation data available for D3.


Justification for classification or non-classification

Based on the available read-across information, 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane is not classified for skin or eye irritation according to Regulation (EC) No 1272/2008.