2-pentylcyclopent-2-en-1-one

Endpoint summary

Description of key information

In a reliable study, the acute oral toxicity test of Pentyl Cyclopentenone FAB was determined to be between 2.0 and 5.0 mL/kg bw. No acute dermal or inhalation studies were available.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Qualifier:

no guideline available

Principles of method if other than guideline:

This test is performed for each suspected low toxic material to determine an appropriate order of toxicity using five male and five female animals. The most relevant dose-level for the class of substance is selected, and three male and three female animals are dosed at this level. Two groups of one male and one female are dosed above and below this level.
Modification of Standard: Range finding determination only

GLP compliance:

no

Remarks:

(The study pre-dated the introduction of GLP in the UK)

Test type:

standard acute method

Limit test:

no

Species:

other: mice

Strain:

not specified

Sex:

male/female

Details on test animals or test system and environmental conditions:

Oral intubation 4-5 week old mice were tested. The animals are placed in individual cages, fasted for four hours and then the animals are individually weighed and intubated with the appropriate volumes of the test material. Each animal on one dosage level receives the same amount per kg body weight.
4 week old rats or mice are usually used for these tests, in which it is possible to intubate a maximum dosage of 100 mL/kg.

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

Maximum dosage volume applied: 100 ml/kg

Doses:

Dose-levels selected for testing:
10.0 mL/kg body weight
5.0 mL/kg body weight
2.0 mL/kg body weight

No. of animals per sex per dose:

10.0 mL/kg body weight - 2 animals treated
5.0 mL/kg body weight - 6 animals treated
2.0 mL/kg body weight - 2 animals treated

Control animals:

not specified

Details on study design:

Oral intubation 4-5 week old mice were tested. Groups of mice were intubated at 3 dose levels using graded volumes of the test substance. Animals were observed for up to 7 days after intubation. All animals were autopsied. All survivors were killed and examined post mortem after 7 days.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

2 - 5 mL/kg bw

Based on:

test mat.

Mortality:

One mouse dosed at 5 mL/kg died within 30 mins after intubation. All mice were hypothermic within 1 hour after treatment and within 2 hours both mice doesed at 10 mL/kg and three mice dosed at 5 mL/kg had died. The two remaining mice dosed at 5 mL/kg were found dead after 18 and 42 hours respectively. The mice dosed at 2 mL/kg recovered within 18 hours after treatment.

Clinical signs:

other: Mice dosed at all three levels were comatose or semi-comatose, cyanosed and exhibiting laboured breathing within 30 mins after treatment.

Gross pathology:

Autopsy of the animals that died reveealed slight iritation of the stomach and duodenum with orange fluid present in the duodenum. These mice had pale kidneys and very pale livers.

Interpretation of results:

Toxicity Category V

Remarks:

Migrated information Criteria used for interpretation of results: expert judgment

Conclusions:

The acute toxicity of 2-Pentylcyclopent-2-enone was determined to be between 2 and 5 mL/kg body weight.

Executive summary:

In an acute oral toxicity study, conducted prior to the introduction of GLP or the applicable OECD test guideline, undiluted 2-Pentylcyclopent-2-enone, a group of mice were administered three doses. Animals were observed for clinical signs of toxicity for 7 days and all survivors were examined for gross pathological changes.

One mouse dosed at 5 mL/kg died within 30 mins after intubation. All mice were hypothermic within 1 hour after treatment and within 2 hours both mice doesed at 10 mL/kg and three mice dosed at 5 mL/kg had died. The two remaining mice dosed at 5 mL/kg were found dead after 18 and 42 hours respectively. The mice dosed at 2 mL/kg recovered within 18 hours after treatment.

From the results of this study, the acute oral LD50 of 2-Pentylcyclopent-2-enone in mice was determined to be beetween 2 and 5 mL/kg body weight. Therefore no classification is required under CLP.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

Acceptable

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Based on the results of the acute toxicity study in laboratory animals, classification under EU DSD or CLP regulations as acutely toxic by the oral route is not required.

Justification for selection of acute toxicity – oral endpoint
Reliable in vivo study.