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EC number: 241-881-3 | CAS number: 17955-88-3
- 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
Endpoint summary
Administrative data
Description of key information
In the key skin irritation study, conducted according to OECD TG 404, and in compliance with GLP, the test substance, 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane, was reported to be not irritating to rabbit skin (Aventis, 2001).
In the key in vitro eye irritation study, conducted according to OECD TG 437, and in compliance with GLP, the test substance, 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane, was reported to be not irritating to corneas and the reported in vitro irritation score was 0.35 (Eurofins, 2016).
Key value for chemical safety assessment
Skin irritation / corrosion
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed (not irritating)
Eye irritation
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed (not irritating)
Respiratory irritation
Endpoint conclusion
- Endpoint conclusion:
- no study available
Additional information
In the key skin irritation study, conducted according to OECD TG 404, and in compliance with GLP, the test substance, 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane, was reported to be not irritating to rabbit skin (Aventis, 2001).
Following application of 0.5 mL of undiluted test substance onto the skin of 3 female rabbits, kept in contact with the skin under semiocclusive dressing for 4 hours, no erythema or oedema were observed in any of the test animals at 1, 24, 48 and 72 hours post-application. No signs of systemic toxicity were noted in any of the animals.
A supporting skin irritation study was available, which also concluded the test item to be not irritating to rabbit skin (BRRC, 1995).
In the key in vitro eye irritation study, conducted according to OECD TG 437, and in compliance with GLP, the test substance, 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane, was reported to be not irritating to corneas and the reported in vitro irritation score was 0.35 (< 3) (Eurofins, 2016).
Corneas were excised from eyes collected as a by-product from slaughtered animals. 0.750 µL of undiluted test material was applied to 3 test corneas and incubated for 10 min at 32 +/- 1°C. Following incubation, the corneas were washed three times with MEM to remove residual test material and incubated with RPMI for 2 hours at 32 +/- 1°C, then illuminance measurement was performed. After the measurement, sodium fluorescein solution was added and the corneas were incubated for 90 min at 32 +/- 1°C. The opacity density was determined using a spectrophotometer and the in vitro irritation score was calculated. Negative and positive controls were included and gave the expected results.
Two supporting eye irritation studies were also available, which concluded the test item to be not irritating to rabbit eyes and supported the conclusion from the key study (Aventis, 2001; BRRC, 1995). Both studies were conducted according to an appropriate OECD test guideline or to a protocol similar to it, and in compliance with GLP.
Following 24-hour instillation of 0.1 mL of undiluted test item into the lower lid of 3 female rabbits, conjunctival redness in 2 of the animals as well as colourless eye discharge with moistening of the lids in all of the test animals were observed within 1 hour after administration. All signs of irritation disappeared within 24 hours post-treatment. The treated eyes were washed thoroughly with isotonic saline at 37°C at 24 hours post-instillation. Observations were performed at 1, 24, 48 and 72 hours after treatment (Aventis, 2001).
Following a single instillation of undiluted test material into the eyes of 3 female and 3 male rabbits, minor conjunctival redness with a minor to moderate ocular discharge were evident in all of the test animals. Ocular irritation subsided within 24 hours in 5 animals and 48 hours in 1 animal (BRRC, 1995).
Justification for classification or non-classification
Based on the available data for 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane, no classification is required for skin and eye irritation according to Regulation (EC) No. 1272/2008.
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