Methoxycarbonyloxycyclooct-4-ene

Endpoint summary

Description of key information

Acute oral toxicity: LD50 is >2000 mg/kg bw in an OECD TG 401

Acute toxicity inhalation: LC50 is 6240 mg/m3 using route to route extrapolation and vapour exposure

Acute dermal toxicity: LD50 is >2000 mg/kg bw in an OECD TG 402.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The one acute oral toxicity study available is of sufficient quality for the present dossier.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The acute inhalation toxicity is derived using route to route extrapolation from the acute toxicity results, using 100% absorption. This assessment is considered to be sufficiently adequate for covering this endpoint.

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The one acute dermal toxicity study available is of sufficient quality for the present dossier.

Additional information

Acute oral toxicity:

The substance was tested in an acute oral toxicity study with male and female Sprague-Dawley rats (OECD TG 401). Based on the results of a preliminary study, the following doses were used in the main study: 2000, 2500, 3200, 4000 and 5000 mg/kg bw. Deaths occurred amongst male rats dosed at 4000 mg/kg and above and amongst female rats dosed at 2000 g/kg and above within 22 and 47 hours of dosing. Signs of reaction to treatment observed shortly after dosing in all rats were pilo-erection, abnormal body carriage (hunched posture), abnormal gait (waddling), lethargy, decreased respiratory rate, pallor of the extremities and increased salivation. These were accompanied by: ptosis in all male rats treated at 3200 mg/kg and in one male rat treated at 4000 mg/kg, a comatose-like condition amongst rats in all dose groups, increased lacrimation amongst rats dosed at 2500, 3200 and 4000 mg/kg. Recovery as judged by external appearance and behaviour was apparently complete by Day 5. Body weight losses were recorded for all but one of the rats that died and one surviving female at 2000 mg/kg. No abnormalities were observed in surviving animals. In animals that died during the study pallor of the liver, kidneys and spleen were seen. The female LD50 resulted in 2400 mg/kg bw (between 1900 and 2900 mg/kg bw) and the male LD50 resulted in 4200 mg/kg bw (between 3400 and 5500 mg/kg bw).

Acute inhalation toxicity:

The acute inhalation toxicity for the substance can be derived using data on the acute oral toxicity and using the extrapolation formula for inhalation conversion as presented in the ECHA CLP guidance (ECHA CLP guidance (2017, page 250, 3.1.3.3.5), which is: 1 mg/kg bw = 0.0052 mg/L/4hours. The LD50 of the substance for acute oral toxicity is 2400 mg/kg bw. This 2400 mg/kg bw can be converted to 12480 mg/m3 (LD50oral * 5.2 mg/m3). Taking into account the inhalation absorption as 100% and oral absorption 50%, the acute inhalation toxicity would become 6240 mg/m3. The maximum saturated vapour pressure for the substance is 304 mg/m3. This means that the substance cannot reach a vapour concentration higher than 304 mg/m3. The extrapolated inhalation LC50 cannot be reached because it exceeds the saturated vapour pressure by more than a factor of 20.

Acute dermal toxicity:

The substance was tested in an acute dermal toxicity study with male and female Sprague-Dawley rats (OECD TG 402). The substance was administered at a limit dose of 2000 mg/kg bw. After 24 hours of exposure, there were no clinical signs of reaction to treatment in any rat and no mortality occurred. No signs of dermal irritation at the treatment sites were noted during the study. A zero bodyweight gain was recorded for two female rats on day 8. Normal bodyweight gains were recorded for these rats on day 15. At gross pathology no abnormalities were seen. The LD50 result in >2000 mg/kg bw.

Justification for classification or non-classification

The substance does not have to be classified for acute toxicity according to EU CLP (EC No. 1272/2008 and its amendments).