4-chlorobenzonitrile

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

04.02.2014 - 21.02.2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

4-chlorobenzonitrile

EC Number:

210-765-4

EC Name:

4-chlorobenzonitrile

Cas Number:

623-03-0

Molecular formula:

C7H4ClN

IUPAC Name:

4-chlorobenzonitrile

Test material form:

not specified

Details on test material:

- Name of test material (as cited in study report): 4-Chlorobenzonitrile
- Physical state: solid
- Analytical purity: 99.7 %
- Impurities (identity and concentrations): 0.05 % 2-Chlorobenzonitrile; 0.09 % 3-Chlorobenzonitrile; 0.06 % Chlorobenzaldehyde; < 0.05 % 4-Chlorotoluene, Benzonitrile; 0.1 % another organic impurity max.
- Purity test date: 04.09.2013
- Lot/batch No.: 324601
- Expiration date of the lot/batch: 31.12.2015
- Storage condition of test material: Room Temperature (20 +/- 5 °C)

Test animals

Species:

rat

Strain:

other: Crl:(WI)BR

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: TOXI COOP ZRT. Cserkesz u. 90., 1103 Budapest, Hungary
- Age at study initiation: 10 weeks
- Weight at study initiation: 200-220 g
- Fasting period before study: The day before treatment the animals were fasted. The food but not water was withheld overnight.
- Housing: Group caging (3 animals/cage), Type II polypropylene/polycarbonate
- Diet (e.g. ad libitum): ad libitum, ssniff SM R/M-Z+H complete diet for rats and mice produced by ssniff Spezialdiäten GmbH, 59494 Soest, Germany
- Water (e.g. ad libitum): tap water from municipal supply as for human consumption from bottle ad libitum
- Acclimation period: 19 days in first step, 20 days in second step and 21 days in third step

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3 °C
- Humidity (%): 30-70 %
- Air changes (per hr): 10-15 air changes/hour by central air-condition system
- Photoperiod: artificial light from 6 a.am to 6 p.m.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: 1.0 % Methyl Cellulose (Methylcellulosum/Aqua purificata)

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 and 30 mg/L
- Lot/batch no. (if required): Methylcellulosum: N83746634; Aqua purificata: 1311-5507

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg bw

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: Selection on the basis of the available information about the test item

Doses:

2000 and 300 mg/kg bw

No. of animals per sex per dose:

3 females (nulliparous and non pregnant) per dose

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Mortality: 30 min, 1 h, 2 h, 4 h after the treatment and twice each day for 14 days thereafter; General state, external appearance, behavior and clinical symptoms: at least once during the first 30 min, then 1 h, 2 h, 3 h, 4 h after treamtment and once each day for 14 days thereafter; Body weights: recorded on day 0 (just before the treament), on day 7 and on day 15.
- Necropsy of survivors performed: yes

Statistics:

no data

Results and discussion

Preliminary study:

not applicable

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 300 - < 2 000

Based on:

test mat.

Remarks on result:

other: The Method according to OECD 423 is not intended for the precise calculation of a precise LD50 value.

Mortality:

All animals treated with 2000 mg/kg bw single oral dose of the test item 4-Chlorobenzonitrile were sacrificed as moribund on Day 1.
No death occurred at 300 mg/kg bw single oral dose of the test item. All female rats in step 2 and step 3 survived until the end of the 14-day observation period.

Clinical signs:

other: In group 1 treated with 2000 mg/kg bw dose clinical sign of reaction comprised of decreased activity (18 cases of 18 observations), clonic convulsion (3/18), abnormal gait (12/18), prostration (3/18), crouching (9/18), incoordination (6/18), decreased rig

Gross pathology:

All rats treated with 2000 mg/kg bw dose of the test item were sacrificed as moribund on Day 1. All animals of the 300 mg/kg bw dose survived until the scheduled necropsy on Day 15. External necropsy findings as piloerection and lacrimation were detected in all animals of group 1. Internal necropsy finding as pale kidneys was observed in two animals (No.: 9978, 9982) of group 1. This alteration could not be related to the test item toxic effect, but was regarded an individual variation. Most likely the observation is a congenital anomaly. Slight hydrometra was observed in female No.: 9987 of the group 2 and two females (No: 9977, 9985) of group 2. It is physiological finding and connected to the cycle of the animal.

No macroscopical changes were found related to the effect of the test item during the macroscopic examination of the animals of 300 mg/kg bw dose group.

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

In conclusion, the LD50 of the test item4-Chlorobenzonitrile is between 300 and 2000 mg/kg bodyweight by oral route in the rat.
In accordance with the OECD Guideline No. 423 (Annex 2d), the LD50 cut-off of the test item may be considered to be 500 mg/kg body weight by oral route in the rat.

Executive summary:

In an acute oral toxicity study according to OECD 423 with 4-Chlorbenzonitrile the starting dose was selected on the basis of the available information about the test item.

The acute toxic class method was carried out involving a stepwise procedure with the use of 2000 mg/kg bw as the starting dose in three female rats. All animals died in step 1, so the test was continued at a lower dose level (300 mg/kg bw) on further three female rats. Since no animal died in step 2, the test was repeated at same dose level (300 mg/kg bw) on further three female rats. There was no death in the third step, too, so the test was finished because the stopping criteria of Annex 2d of OECD Guideline No. 423 was met.

Animals were weighed, observed for lethality and toxic symptoms for 14 days after the treatment. Gross pathological examination was carried out in moribund animals on Day 1, as well as 15th day after the treatment in survivor animals.

In conclusion, the LD50 of 4-Chlorobenzonitrile is between 300 and 2000 mg/kg bodyweight by oral route in the rat. In accordance with the OECD Guideline No. 423 (Annex 2d), the LD50 cut-off of the test item may be considered to be 500 mg/kg body weight by oral route in the rat.