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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Description of key information

In the key acute oral toxicity study, conducted according to OECD TG 423, and in compliance with GLP, the reported LD50 value for 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane was > 2000 mg/kg bw in rats (Eurofins, 2016).

In the key acute dermal toxicity study, conducted according to OECD TG 402, and in compliance with GLP, the reported LD50 value for 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane was > 2000 mg/kg bw (Eurofins, 2016).

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
Value:
2 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
Value:
2 000 mg/kg bw

Additional information

In the key acute oral toxicity study, conducted according to OECD TG 423, and in compliance with GLP, the reported LD50 value for 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane was > 2000 mg/kg bw in rats (Eurofins, 2016).

Following oral administration of 2000 mg/kg bw of undiluted test substance to 5 male and 5 female rats, no mortality occurred during the 14 -day study period. No signs of systemic toxicity were observed in any of the animals. No test substance-related macroscopic abnormalities were observed in any of the test animals. The expected body weight gain was noted in all of the animals. The rats were examined at 30 min, then 1 hour, as well as once a day for 14 days after administration.

Two supporting studies were also available, which support the findings of the key acute oral toxicity study (Aventis, 2001; BRRC, 1995). The reported LD50 value for 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane was > 2000 mg/kg bw in both studies. No test substance-induced mortality, signs of systemic toxicity or pathological abnormalities were reported in any of the studies.

In the key acute dermal toxicity study, conducted according to OECD TG 402, and in compliance with GLP, the reported LD50 value for 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane was > 2000 mg/kg bw (Eurofins, 2016).

Following dermal application of 2000 mg/kg bw onto the skin of 5 male and 5 female rats, kept in contact with the skin under occlusive dressing for 24 hours, no mortality occurred during the 14 -day study period. No clinical signs of toxicity or pathological abnormalities were evident in any of the test animals during the observation period or at necropsy. The expected body weight gain was noted in all of the test animals. The rats were examined at 30 min, then 1 hour, as well as once a day for 14 days after administration.

One supporting study was also available, which supports the findings of the key acute dermal toxicity study (BRRC, 1995). The reported LD50 value for 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane was > 2000 mg/kg bw. No test substance-induced mortality, signs of systemic toxicity or pathological abnormalities were reported in any of the studies.


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 acute toxicity according to Regulation (EC) No. 1272/2008.