Cyclopentene

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1975

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: comparable to guideline study with acceptable restrictions; No post-exposure observation time, no necropsy performed.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1975

Report date:

2017

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

yes

Remarks:

no post-exposure observation time, no necropsy performed

GLP compliance:

no

Test type:

standard acute method

Test material

Test material information

Constituent 1

Reference substance name:

Cyclopentene

EC Number:

205-532-9

EC Name:

Cyclopentene

Cas Number:

142-29-0

Molecular formula:

C5H8

IUPAC Name:

cyclopentene

Details on test material:

- Analytical purity: 99.8 % (technical)

Specific details on test material used for the study:

Appearance: pale yellow liquid
Qualities: specific gravity=0.772/20°C, slightly water-soluble, readily soluble in alcohols, hydrocarbons and chlorinated hydrocarbons

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Sex: male and female
- Weight at study initiation: 140-150 g
- Fasting period before study: not specified
- Housing: air-conditioned animal quarters, in groups of 5 in cages
- Diet (e.g. ad libitum): ad libitum ( Altromin standard diet)
- Water (e.g. ad libitum): ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21°C +/-2°C
- Photoperiod (hrs dark / hrs light): 12/12 (lit from 7am-7pm daily)

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

not specified

Details on inhalation exposure:

- Rats were exposed to vapours for 4 hours in dynamic inhalation chambers.


- During the 3-week and 12-week periods, the rats were exposed to the vapour concentrations 6 hrs/day for 5days/week.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

5,8; 11,3; 16,9; 22,9 mg/l
(original dose levels: 2040, 4015, 5980 and 8110 ppm/ 4h.)

No. of animals per sex per dose:

Each group consisted of 10 male and 10 female rats.

Control animals:

yes

Remarks:

Inhaled air only.

Details on study design:

10 rats of each sex were exposed to vapours for 4 hr in dynamic inhalation chambers.

Statistics:

Not specified

Results and discussion

Preliminary study:

Not applicable

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 22.9 mg/L air

Exp. duration:

4 h

Remarks on result:

other: vapour

Remarks:

22.9 mg/L = 8100 ppm = 22564.05 mg/m^3

Mortality:

No mortalities.

Clinical signs:

other: After a 4-hr exposure to cyclopentene concentrations of 11,3 mg/l or less animals showed no toxic symptoms.

Other findings:

- The animals (males and females) exposed to higher concentrations developed symptoms which consisted of irritation of the mucosa of the upper airways

Any other information on results incl. tables

Subacute inhalation toxicity

- During and after the 3 -week exposure (870 and 3100 ppm), the rats did not show any significant changes in appearance and behaviour.

- A reduced body weight gain was seen in female rats exposed to 3100 ppm.

- Autopsy revealed no signs of changes in the organs.

Subchronic inhalation toxicity

- The 1120 ppm exposure for 12 weeks caused no noticeable changes in appearance, behaviour or body weight..

- The haemotological values, serum-enzyme activities and serum concentrations of urea, creatinine, bilirubin and glucose were within the physiological range and there was no significant change in the composition of the urine.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the results of this study, it can be concluded that the LC50 after a 4 -hour exposure to cyclopentene was > 22.9 mg/L air in male and female rats.

Executive summary:

This study was an investigation evaluating the acute, subacute and subchronic inhalation toxicity of the test substance, Cylopentene.

Acute toxicity:

After a 4 -hour exposure to about 4000 ppm or less of cyclopentene, there were no observable toxic symptoms, but those animals exposed to higher concentrations, developed an irritation of the mucosa of the upper airways. This was seen in both males and females.

It can be concluded that the LC50 after a 4 -hour exposure to cyclopentene was > 22.9 mg/L air in male and female rats.