Cyclohexylbenzene

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well documented GLP study according to international guideline.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 425 (Acute Oral Toxicity: Up-and-Down Procedure)

Version / remarks:

adopted 21 September 1998

GLP compliance:

yes (incl. QA statement)

Test type:

up-and-down procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Cyclohexylbenzene

EC Number:

212-572-0

EC Name:

Cyclohexylbenzene

Cas Number:

827-52-1

Molecular formula:

C12H16

IUPAC Name:

cyclohexylbenzene

Details on test material:

- Name of test material (as cited in study report): phenylcyclohexane
- Description: clear colourless liquid
- Date received: 2001-08-06
- Storage conditions: room temperature, in the dark

Test animals

Species:

rat

Strain:

other: Sprague-Dawley CD (Crl: CD® (SD) IGS BR)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (UK) Ltd, Margate, Kent, UK
- Age at study initiation: approximately 8 weeks
- Weight at study initiation: ≥ 200g
- Fasting period before study: overnight immediately before dosing
- Housing: females individually and males in group of 3 in solid-floor polypropylene cages furnished with woodflakes
- Diet: ad libitum (Rat and Mouse Expanded Diet No. 1, Special Diets Services Limited, Witham, Essex, UK) with exception of an overnight fast immediately before dosing and approximately 3 to 4 h after dosing
- Water: ad libitum
- Acclimation period: ≥ 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-25
- Humidity (%): 30-70
- Air changes (per hr): ≥ 15
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

3

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: Observations for deaths or overt signs of toxicity 1/2, 1, 2 and 4 h after dosing and subsequently once daily for 14 days. Individual body weights were recorded prior to dosing and 7 and 14 days after treatment.
- Necropsy of survivors performed: yes

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No deaths

Clinical signs:

other: Hunched posture was noted in 2 females. Signs of systemic toxicity also noted in one of these females were decreased respiratory rate, laboured respiration, ataxia and emaciation. These 2 females recovered 2 or 6 days after dosing. There were no signs of

Gross pathology:

No abnormalities

Applicant's summary and conclusion

Interpretation of results:

practically nontoxic

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The acute oral median lethal dose (LD50) in the Sprague-Dawley CD (Crl CD® (SD) IGS BR) strain rat was found to be greater than 2000 mg/kg bw.

Executive summary:

The study was performed to assess the acute oral toxicity of the test material following a single oral administration in the Sprague-Dawley CD (Crl CD® (SD) IGS BR) strain rat. The study was carried out according to OECD guideline 425.

One fasted female animal was treated with the test material at dose level of 2000 mg/kg. A second and a third fasted female rat were also treated at a dose level of 2000 mg/kg. This was then followed by a group of 3 fasted male rats at the same dose level.

The test material was administered orally undiluted. Clinical signs and body weight development were monitored during the study. All animals were subjected to gross necropsy.

There were no deaths. Hunched posture was noted in 2 females. Signs of systemic toxicity also noted in one female were decreased respiratory rate, laboured respiration, ataxia and emaciation. There were no signs of systemic toxicity noted in one female and all males.

All animals showed expected gains in body weight over the study period. No abnormalities were noted at necropsy.

The acute oral median lethal dose (LD50) was found to be greater than 2000 mg/kg bw.