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Administrative data

Description of key information

Ethoxybenzonitril is harmful after single oral exposure (LD50 cut-off, rat: > 500 - < 1000 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:
April 2000
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP guideline study
Qualifier:
according to
Guideline:
OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.1 (Acute Toxicity (Oral))
Deviations:
no
GLP compliance:
yes
Test type:
acute toxic class method
Limit test:
yes
Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Harlan Winkelmann, Borchen, Germany
- Strain: Hsd Cpb:WU (SPF)
- Age at study initiation: 8-9 weeks
- Mean weight at study initiation: 216-241 g (males) or 167-182 g (females)
- Housing: in groups of 3 animals
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 2
- Humidity (%): approx. 55 +/- 5
- Air changes (per hr): approx. 15-20
- Photoperiod (hrs dark / hrs light): 12 / 12
Route of administration:
oral: gavage
Vehicle:
other: formulated in demineralized water with the aid of Cremophor EL 2% (v/v)
Details on oral exposure:
- Application volume: 10 mL/kg bw

- Rationale for the selection of the starting dose:
As described in the flow charts of Annex 2, OECD guideline 423, the starting dose level should be that which is most likely to produce mortality in
some of the dosed animals. Therefore, the limit dose 2000 mg/kg bw was chosen as starting dose.
Doses:
200, 500 mg/kg (males and females), 2000 mg/kg (females)
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 and weighing: at least once daily (clinical signs, mortality) or once weekly (weight gain)
- Necropsy of survivors performed: yes
Statistics:
none
Sex:
male/female
Dose descriptor:
other: LD50 cut-off
Effect level:
> 500 - < 1 000 mg/kg bw
Based on:
test mat.
Mortality:
The dose of 2000 mg/kg bw was lethal in females. All females died from 4 hours after administration up to day 3 of the study. All males and females of the dose groups 200 and 500 mg/kg bw survived
Clinical signs:
At 200 mg/kg bw the motility and reactivity were decreased in females, and both genders showed increased salivation. At 500 mg/kg bw in both genders the motility and reactivity were decreased , the gait uncoordinated and/or temporary creeping, the breathing labored, the salivation increased, and the palpebral fissures temporary narrowed. In females also poor reflexes were observed. Additionally to the signs above, females of the dose group 2000 mg/kg bw showed dazed condition, they lay in lateral position, and a spasmodic state was observed.
Body weight:
Body weight and body weight development of male and female rats were not affected by treatment.
Gross pathology:
In the female animals that died during the observation period a dark-red or clay-colored discoloration of liver, a pale discoloration of kidneys and autolysis were detected. The animals sacrificed at the end of study showed no gross pathological findings.
Other findings:
none
Interpretation of results:
harmful
Remarks:
Migrated information
Executive summary:

The acute oral toxicity of Ethoxybenzonitril was moderate with a LD50 > 500 - < 1000 mg/kg bw in rats (cut-off value) according to OECD TG 423. All females died after administration of 2000 mg/kg bw. All males and females of the dose groups 200 and 500 mg/kg bw survived. Clinical signs were observed at 200 mg/kg bw and above in both genders. Body weight development was not affected until 2000 mg/kg bw. In animals that died during the observation period a dark-red or clay-colored discoloration of liver, a pale discoloration of kidneys and autolysis were detected.

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Quality of whole database:
The study is GLP compliant and is of high quality (Klimisch score=1)

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

The acute oral toxicity of Ethoxybenzonitril was moderate with a LD50 > 500 - < 1000 mg/kg bw in rats (cut-off value) according to OECD TG 423 (Krötlinger, 2000). All females died after administration of 2000 mg/kg bw. All males and females of the dose groups 200 and 500 mg/kg bw survived. Clinical signs were observed at 200 mg/kg bw and above in both genders. Body weight development was not affected until 2000 mg/kg bw. In animals that died during the observation period a dark-red or clay-colored discoloration of liver, a pale discoloration of kidneys and autolysis were detected.


Justification for selection of acute toxicity – oral endpoint
Only one study available

Justification for classification or non-classification

Based on the study results (oral LD50 cut-off value: > 500 - < 1000 mg/kg bw ) a classification with R22 (harmful if swallowed) according to Directive 67/548/EEC or with Acute Toxicity Cat. 4 (H302:harmful if swallowed) according to Regulation (EC) No. 1272/2008 (CLP) is required.