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EC number: 217-496-1 | CAS number: 1873-88-7
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
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Endpoint summary
Administrative data
Description of key information
No skin sensitization data are available for the registered substance 1,1,1,3,5,5,5,-heptamethyltrisiloxane, therefore good quality data for the related substance octamethyltrisiloxane (L3, CAS 107-51-7) have been read-across.
In a key skin sensitization study conducted according to OECD Test Guideline 406 and in compliance with GLP, octamethyltrisiloxane was not sensitising to the skin of guinea-pig (RCC 1999).
Key value for chemical safety assessment
Skin sensitisation
Link to relevant study records
- Endpoint:
- skin sensitisation: in vivo (non-LLNA)
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 01 Dec 1998 - 15 Feb 1999
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 406 (Skin Sensitisation)
- Qualifier:
- according to guideline
- Guideline:
- EU Method B.6 (Skin Sensitisation)
- GLP compliance:
- yes (incl. QA statement)
- Type of study:
- guinea pig maximisation test
- Justification for non-LLNA method:
- An LLNA study was not performed because there is an existing reliable study for skin sensitisation using the Guinea Pig Maximisation test method. Furthermore, the LLNA test method is not considered to be suitable for substances that contain silicon. Please refer to the attached document for further details.
- Species:
- guinea pig
- Strain:
- other: Ibm: GOHI; SPF- quality guinea pigs
- Sex:
- male/female
- Details on test animals and environmental conditions:
- TEST ANIMALS
- Source: RCC Ltd, Biotechnology & Animal Breeding Division, Wolferstrasse 4, CH-4414 Fullinsdorf, Switzerland
- Age at study initiation: 5-7 weeks
- Weight at beginning of acclimation period: 304-380 g
- Housing: Individually in Makrolon type-4 cages with standard softwood bedding
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: One week for the control and test group under test conditions after health examination. No acclimation of animals of the pre-test. Only animals without any visible signs of illness were used.
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12 - Route:
- intradermal and epicutaneous
- Vehicle:
- olive oil
- Concentration / amount:
- Induction 100%, challenge 50%, positive control: intradermal induction 5% , epidermal induction 50% , challenge 50% (vehicle mineral oil)
- No.:
- #1
- Route:
- epicutaneous, occlusive
- Vehicle:
- olive oil
- Concentration / amount:
- Induction 100%, challenge 50%, positive control: intradermal induction 5% , epidermal induction 50% , challenge 50% (vehicle mineral oil)
- No. of animals per dose:
- Control group: 5
Test group: 10
Intradermal pre-test: 1
Epidermal pre-test: 2
Positive control: 10 test, 5 control - Details on study design:
- PRE TEST: This was carried out to identify a suitable concentration of the test article for the induction phase of the main study and a non-irritant concentration for the challenge phase. The concentrations tested were for the epidermal application the most qualified to assure an optimum technical application procedure and for the intradermal injection the selected concentrations were tested at 1, 3 and 5%.
MAIN STUDY:
INTRADERMAL INJECTIONS (DAY 1)
Three pairs of intradermal injections (0.1 ml/sire) were made at the border of a 4x6 cm area in the clipped region as follows:
TEST GROUP:
1. 1:1 (v/v) mixture of FCA and physiological saline.
2. The test article, at 5% in olive oil.
3. The test article at 5% in a 1:1 (v/v) mixture of FCA and physiological saline
CONTROL GROUP:
1. 1:1 (v/v) mixture of FCA and physiological saline.
2. Olive oil.
3. 1:1 (w/w) mixture of olive oil in a 1:1 (v/v) mixture of FCA and physiological saline.
EPIDERMAL APPLICATIONS (DAY 8)
TEST GROUP:
One week after the injections the scapular area was shaved free of hair again prior to the epidermal application. Filter paper was saturated with the undiluted test material and placed over the injection sites of the test animals. The volume of the test article was ca. 0.3 ml. The patch was covered with aluminium foil and firmly secured by an elastic plaster wrapped around the trunk of the animal and secured with impervious adhesive tape. The dressings were left in place for 48 hours. The epidermal application procedure described ensured intensive contact of the test article. The reaction sites were assessed for erythema and oedema 24 and 48 hours after removal of the dressing, using the numerical grading system according to Draize.
CONTROL GROUP:
The guinea pigs of the control group were treated as described above with olive oil only, also applied at a volume of ca. 0.3 ml.
CHALLENGE TEST (DAY 22)
The test and control animals were challenged two weeks after the epidermal induction application. The test and control guinea pigs were treated in the same way.
Hair was clipped and shaved from a 5x5 cm area on the left and right flank of each guinea pig just prior to application. Two patches of filter paper were saturated with the test article at the highest non-irritating concentration of 50% (left flank) and the vehicle only (olive oil applied to the right flank) using the same method as for the epidermal application. The volume of test article or vehicle applied was approximately 0.2 ml. The dressings were left in place for 24 hours.
After ca. 21 hours after removal of the dressing the test sites treated with the test article were depilated as described in the epidermal pre-test. Approximately 24 and 48 hours after the removal of the dressing the application sites were assessed for erythema and oedema using the numerical scoring system according to Draize. - Challenge controls:
- Challenge controls were treated in the same way as the test group.
- Positive control substance(s):
- yes
- Remarks:
- 2-mercaptobenzothiazole
- Reading:
- 1st reading
- Hours after challenge:
- 24
- Group:
- positive control
- Dose level:
- 10%
- No. with + reactions:
- 9
- Total no. in group:
- 10
- Remarks on result:
- positive indication of skin sensitisation
- Reading:
- 2nd reading
- Hours after challenge:
- 48
- Group:
- positive control
- Dose level:
- 10%
- No. with + reactions:
- 10
- Total no. in group:
- 10
- Remarks on result:
- positive indication of skin sensitisation
- Reading:
- 1st reading
- Hours after challenge:
- 24
- Group:
- negative control
- Dose level:
- 50% in olive oil
- No. with + reactions:
- 0
- Total no. in group:
- 5
- Remarks on result:
- no indication of skin sensitisation
- Reading:
- 2nd reading
- Hours after challenge:
- 48
- Group:
- negative control
- Dose level:
- 50% in olive oil
- No. with + reactions:
- 0
- Total no. in group:
- 5
- Remarks on result:
- no indication of skin sensitisation
- Reading:
- 1st reading
- Hours after challenge:
- 24
- Group:
- test chemical
- Dose level:
- 50% in olive oil
- No. with + reactions:
- 0
- Total no. in group:
- 10
- Remarks on result:
- no indication of skin sensitisation
- Reading:
- 2nd reading
- Hours after challenge:
- 48
- Group:
- test chemical
- Dose level:
- 50% in olive oil
- No. with + reactions:
- 0
- Total no. in group:
- 10
- Remarks on result:
- no indication of skin sensitisation
- Interpretation of results:
- GHS criteria not met
- Conclusions:
- The test material was found not sensitising in a reliable study conducted according to OECD Test Guideline 406l, and in compliance with GLP.
Reference
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed (not sensitising)
- Additional information:
No skin sensitization data were available for the registered substance, 1,1,1,3,5,5,5,-heptamethyltrisiloxane, therefore the key study for the structurally analogous substance octamethyltrisiloxane (L3,CAS 107-51-7) was used as read across.
Octamethyltrisiloxane has been tested in a Guinea-Pig Maximisation test conducted according to OECD Test Guideline 406. During the induction phase the guinea-pigs (10 test group and 5 control group, males and females) were injected intradermally with 5% test substance in olive oil and in an emulsion of FCA/physiological saline and thereafter, topically treated with 100% test substance.
After a latency of 14 days, to allow a potential reaction of the immune system, the animals were challenged with 50% of the test substance in olive oil under occlusive dressing. The animals of the control were induced with olive oil and FCA/physiological saline and challenged similarly to those of the test group. Cutaneous reactions, i.e., erythema and eschar, as well as oedema formation were evaluated at 24 and 48 hours after removal of the dressing. No toxic symptoms were evident in the guinea pigs of the control or the test group. No deaths occurred. None of the animals of the tes group were observed with erythematous reactions after treatment with a test article concentration of 50% in olive oil. Therefore the test article is considered not to be a sensitizer when used under the described test conditions.
Respiratory sensitisation
Endpoint conclusion
- Endpoint conclusion:
- no study available
Justification for classification or non-classification
Based on the available data from the structurally analogous substance octamethyltrisiloxane (L3, CAS 107-51-7), the registered substance 1,1,1,3,5,5,5,-heptamethyltrisiloxane does not require classification in accordance with Regulation (EC) No 1272/2008.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
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