Cyclopentene

Endpoint summary

Description of key information

Acute Oral Toxicity

A range-finding toxicity study was conducted with Wistar rats using a variety of substances, including the test substance, cyclopentene. The test substance was administered to Wistar rats as a single oral LD50 dose via oral gavage. Cyclopentene was shown to have a single dose LD50 in rats of 1656 mg/kg.

Acute Inhalation Toxicity

The Kimmerle 1975 study was an investigation evaluating the acute, subacute and subchronic inhalation toxicity of the test substance, Cylopentene.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.

Acute Dermal Toxicity

A range-finding toxicity study was conducted with New Zealand white rabbits using a variety of substances, including the test substance, cyclopentene. After a 24 -hour exposure to cyclopentene was shown to have a single skin penetration LD50 of 1231 mg/kg bw.

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

Study period:

1969

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restrictions; no necropsy performed; no data about doses used; no mortality data available.

Qualifier:

no guideline followed

Principles of method if other than guideline:

Method is described in the publication of Smyth et al (cf. Reference)
Gastric intubation of groups of 5 non-fasted male Carworth-Wistar rats (age: 4-5 weeks; bw: 90-120 g). The dosages were arranged in a logarithmic series differing by a factor of two. 14 days post-exposure observation period. No further details.

GLP compliance:

not specified

Test type:

other: Smyth and Carpenter (see reference)

Limit test:

yes

Specific details on test material used for the study:

Not specified

Species:

rat

Strain:

Wistar

Sex:

male

Details on test animals or test system and environmental conditions:

Not specified

Route of administration:

oral: gavage

Vehicle:

not specified

Details on oral exposure:

Not specified

Doses:

1656.0 mg/kg bw (Original value 2.14 ml/kg (density cyclopentene 0.774 g/ml);
As no information about the number of administered dose levels is given, the total amount of animals could not be determined.

No. of animals per sex per dose:

5

Control animals:

not specified

Details on study design:

Experimental methods remained unchanged and are described in the 1962 publication.

Statistics:

Not specified

Preliminary study:

Not applicable

Key result

Sex:

male

Dose descriptor:

LD50

Remarks:

Single oral LD50

Effect level:

ca. 1 656 mg/kg bw

Based on:

test mat.

Mortality:

4/6 rats died following a 4-hour exposure to cyclopentene at 4000 rpm (inhalation of metered vapour concentration)

Clinical signs:

other: Not specified

Gross pathology:

Not specified

Other findings:

Not specified

Interpretation of results:

Category 4 based on GHS criteria

Remarks:

according to EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008

Conclusions:

Based on the results of the study, cyclopentene had a single dose LD50 in rats of 1656 mg/kg.

Executive summary:

A range-finding toxicity study was conducted with Wistar rats using a variety of substances, including the test substance, cyclopentene. The test substance was administered to Wistar rats as a single oral LD50 dose via oral gavage. Cyclopentene was shown to have a single dose LD50 in rats of 1656 mg/kg.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

1 656 mg/kg bw

Acute toxicity: via inhalation route

Link to relevant study records

Reference

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.

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

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

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)

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

Preliminary study:

Not applicable

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

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.

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.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LC50

Value:

22 564.05 mg/m³ air

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1969

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: comparable to guideline study with acceptable restrictions; only 4 male animals per dose were used; Regarding the occlusive dressing the test protocol used was harsher; no necropsy performed

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

only 4 male animals per dose were used; occlusive dressing; no necropsy performed

Principles of method if other than guideline:

Method is described in the publication of Smyth et al (cf. Reference)

GLP compliance:

no

Test type:

standard acute method

Limit test:

yes

Specific details on test material used for the study:

Not specified

Species:

rabbit

Strain:

New Zealand White

Sex:

male

Details on test animals or test system and environmental conditions:

- Weight at study initiation: 2.5 - 3.5 kg

Type of coverage:

occlusive

Vehicle:

not specified

Details on dermal exposure:

Refer to the publication of Smyth et al (cf. Reference)

Duration of exposure:

24 hours

Doses:

As no information about the number of administered dose levels is given, the total amount of animals could not be determined.

No. of animals per sex per dose:

4

Control animals:

not specified

Details on study design:

The fur is removed from the entire trunk by clipping and the dose is retained beneath an impervious plastic film.
The animals were immobilized during the contact period; 14 days post-exposure observation period.

Statistics:

Not specified

Preliminary study:

Not applicable.

Key result

Sex:

male

Dose descriptor:

LD50

Effect level:

1 231 mg/kg bw

Mortality:

No mortalities.

Clinical signs:

other: Irritation on uncovered rat belly = 5

Gross pathology:

Not specified

Other findings:

Not specified

Value of LD50 given in the literature was 1.59 ml/kg. With respect to the density of cyclopentene (0.774 g/ml), the value in mg/ml refers to 1231 mg/kg.

Interpretation of results:

Category 4 based on GHS criteria

Remarks:

according to EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008

Conclusions:

Based on the results of the study, cyclopentene had a single skin penetration LD50 in rabbits of 1231 mg/kg bw.

Executive summary:

A range-finding toxicity study was conducted with New Zealand white rabbits using a variety of substances, including the test substance, cyclopentene. After a 24 -hour exposure to cyclopentene was shown to have a single skin penetration LD50 of 1231 mg/kg bw.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

1 231 mg/kg bw

Justification for classification or non-classification

Based on the results, Cyclopentene is classified as Category 4 for acute oral and acute dermal toxicity according to EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.