Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
14.01.- 14.06.2016
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2016
Report Date:
2016

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 425 (Acute Oral Toxicity: Up-and-Down Procedure)
Qualifier:
according to
Guideline:
EPA OPPTS 870.1100 (Acute Oral Toxicity)
GLP compliance:
yes (incl. certificate)
Test type:
up-and-down procedure
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
impurity
Type:
impurity
Test material form:
solid: bulk
Details on test material:
This composition is the usual techical grade of AlzChem AG. It will be used when test substance has this composition (or is very closed) or no specific information is available.
Specific details on test material used for the study:
Batch-No.: 529301

Test animals

Species:
rat
Strain:
Wistar
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River, 97633 Sulzfeld, Germany
- Females nulliparous and non-pregnant: yes
- Age at study initiation: 8 - 12 weeks
- Weight at study initiation:150 - 184 g
- Fasting period before study: 16 - 19 hours
- Housing: The animals were kept in groups in IVC cages, type III H, polysulphona cages on Altromin saw fibre beeding.
- Diet: Free access to Altromin 1324 maintenance diet for rats and mice (lot. no. 2922)
- Water: Free access to tap water, sulphur acified to a pH value of approximately 2.8 (drinking water, municipal residue control, microbiological controls at regular intervals)
- Acclimation period: At least five days under laboratory conditions.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3 °C
- Humidity (%): 55 +/- 10 %
- Air changes (per hr): 10 x/ hour
- Photoperiod: Artificial light, sequence being 12 hours light, 12 hours dark.

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
corn oil
Details on oral exposure:
VEHICLE
- Amount of vehicle (if gavage): 10 mL/kg body weight
- Justification for choice of vehicle: While aqua ad injectionem (sterile water) was not adequate, preparation with corn oil yielded a suspension which was technically applicable to the animals.
- Lot/batch no.: 529301
- Purity: 99.7 %

MAXIMUM DOSE VOLUME APPLIED:
10 mL/kg body weight
Doses:
2000, 550 and 175 mg/kg body weight
No. of animals per sex per dose:
2000 mg/kg bw: 4 females
550 mg/kg bw: 4 females
175 mg/kg bw: 2 females
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations: A careful examination was made several times on the day of dosing (at least once during the first 30 minutes and with special attention given during the first 4 hours post-dose). As soon as symptomy were noticed they were recorded. Thereafter, the animals were observed for clinical signs once daily until the end of the observation period. All abnormalities were recorded. Cageside observations included changes in the skin and fur, eyes and mucous membranes. Also respiratory, circulatory, automic and central nervous systems and somatomotor activitiy and behaviour pattern were examined. Particular attention was directed to observations of tremor, convulsions,salivation, diarrhoea, lethargy, sleep and coma.
- Frequency of weighing: The animals were weighed on day 1 (prior to the administration) and on days 8 and 15.
- Necropsy of survivors performed: yes

Results and discussion

Effect levels
Key result
Sex:
female
Dose descriptor:
LD50 cut-off
Effect level:
550 mg/kg bw
Based on:
test mat.
Mortality:
All animals treated with the test item at a dose of 2000 mg/kg bw and one animal treated with the test item at a dose of 550 mg/kg had to be sacrified for ethical reasons on test day1. All remaining animals survived until the end of the study.
Clinical signs:
The most relevant clinical findings in the animals treated with the test item at a dose of 2000 mg/kg bw were reduced spontaneous activity, apathy, prone position, ataxia, slow movements, wasp waist, eyes half closed, eyes closed, abnormal breathing, hypothermia, lacrimation and comatose.

The most relevant clinical findings in the animals treated with the test item at a dose of 550 mg/kg bw were reduced spontaneous activity, prone position, hunched posture, ataxia, slow movements, moving the bedding, wasp waist, eyes half closed, piloerection, abnormal breathing, lacrimation and salivation.

The most relevant clinical findings in the animals treated with the test item at a dose of 175 mg/kg bw were reduced spontaneous activity, hunched posture, slow movements, wasp waist, piloerection, eyes half closed and eyes closed.
Body weight:
All surviving animals gained weight during the observation period. Througout the 14-day observation period, the weight gain of surviving animals was within the normal range of variation for this strain.
Gross pathology:
With the expection of acute injection of blood vessels in the abdominal region, which is due to the euthanasia injection, no specific gross pathological changes were recordedfor any other animal. At necropsy, in the stomach of animal 1 (2000 mg/kg bw) residual test item was found.

Applicant's summary and conclusion

Interpretation of results:
Category 4 based on GHS criteria
Conclusions:
Under the conditions of the present study and according to OECD Guideline 425 and OPPTS 871.1100 the estimated LD50 of the test item 2,3-Dichlorobenzonitrile in rats is 550 mg/kg bw (based on an assumed sigma of 0.5).
Executive summary:

In order to evalute the acute toxic potential of 2,3 -Dichlorobenzonitrile a study according to OECD 425 and OPPTS 871 .1100 was performed.

All animals treated with the test item at a dose of 2000 mg/kg bw and one animal treated with the test item at a dose of 550 mg/kg had to be sacrified for ethical reasons on test day1. All remaining animals survived until the end of the study.

The most relevant clinical findings in the animals treated with the test item at a dose of 2000 mg/kg bw were reduced spontaneous activity, apathy, prone position, ataxia, slow movements, wasp waist, eyes half closed, eyes closed, abnormal breathing, hypothermia, lacrimation and comatose. The most relevant clinical findings in the animals treated with the test item at a dose of 550 mg/kg bw were reduced spontaneous activity, prone position, hunched posture, ataxia, slow movements, moving the bedding, wasp waist, eyes half closed, piloerection, abnormal breathing, lacrimation and salivation. The most relevant clinical findings in the animals treated with the test item at a dose of 175 mg/kg bw were reduced spontaneous activity, hunched posture, slow movements, wasp waist, piloerection, eyes half closed and eyes closed.

All surviving animals gained weight during the observation period. Througout the 14-day observation period, the weight gain of surviving animals was within the normal range of variation for this strain.

With the expection of acute injection of blood vessels in the abdominal region, which is due to the euthanasia injection, no specific gross pathological changes were recorded for any other animal. At necropsy, in the stomach of animal 1 (2000 mg/kg bw) residual test item was found.

Under the conditions of the present study and according to OECD Guideline 425 and OPPTS 871.1100 the estimated LD50 of the test item 2,3-Dichlorobenzonitrile in rats is 550 mg/kg bw (based on an assumed sigma of 0.5).