Dioctadecyl ether

Endpoint summary

Description of key information

repeated dose toxicity (rat, 90 day study): NOAEL > 1000 mg/kg bw

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion

Dose descriptor:

NOAEL

1 000 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Additional information

The oral toxicity of the test substance dioctylether was tested by daily administration to rats, has been investigated over a period of 13 consecutive weeks.Three groups, each of 10 male and 10 female rats (strain Crl:CD), received the test substance daily by oral gavage (5 ml) at dosages of 100, 300, and 1000 mg/kg/day for a minimum of 13 consecutive weeks. A fourth similarly constituted group received the vehicle alone (sun flower oil) and acted as a control.No death occurred during the study. Daily post‑dose observations did not show any significant signs. Detailed clinical signs with neurotoxicity assessment did not show any treatment‑related effects. Neurotoxicity tests and measurements performed at the end of the treatment did not show changes attributable to the test substance.With regard to body weight, no statistically significant differences were observed between control and treated groups. No test item-related influence was observed in food consumption. No findings were seen in the ophthalmic examination performed at the end of the study. No treatment‑related changes were observed in haematological parameters. No treatment‑related changes were seen in clinical chemistry parameters. No treatment-related pathological and histopathological changes were seen.No changes were seen in urinalysis. Treatment with 1000 mg/kg bw caused an increase in the absolute and related liver and kidney weights by up to 280 %. The increase is considered to be a non-specific adaptive change to the high work load of the liver caused by a dose level of 1000 mg/kg bw.Under the present test conditions, the no-observed-adverse-effect-level (NOAEL) for the test article was above 1000 mg/kg bw for systemic changes.

Dioctylether is used as a read-across substance for distearylether. The only difference is the longer alkyl chain. Dioctylether is regarded as a worst case in this respect because of the higher bioavailability due to the lower molecular weight. Furthermore, the possible metabolite stearyl alcohol is also not toxic after repeated oral exposure. It is unlikely that the ether of stearyl alcohol which might be build in the human body could have adverse systemic effects after repeated oral exposure.

Based on the reliability and relevance, this study has been used as key study.

Justification for classification or non-classification

Based on results of the key study the substance does not need to be classified according to GHS (Regulation (EU) 1272/2008) and also does not need to be classified according to DPD (67/548/EEC).