4-ethylbenzaldehyde

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1981

Report date:

1981

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

4-ethylbenzaldehyde

EC Number:

225-268-8

EC Name:

4-ethylbenzaldehyde

Cas Number:

4748-78-1

Molecular formula:

C9H10O

IUPAC Name:

4-ethylbenzaldehyde

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Shizuoka Laboratory Animal Center
- Age at study initiation: 5 weeks
- Weight at study initiation: males 101 ± 4.2 g; females 89 ± 2.0 g
- Fasting period before study: overnight
- Housing: 10 per cage
- Diet: pellet food CE-2 supplied by CLEA Japan, Inc. ad libitum. Feeding was recommenced 3 hours after administration.
- Water: tap water ad libitum
- Acclimation period: 1 week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 24 ± 2
- Humidity (%): 35 to 65

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Doses:

Male: 0.74, 0.97, 1.15, 1.35, 1.55, 1.90, 2.22, 2.58 and 3.05 mg/kg bw
Female: 1.11, 1.33, 1.56, 1.78, 2.18 and 2.53 mg/kg bw

No. of animals per sex per dose:

10

Control animals:

yes

Remarks:

Untreated control

Details on study design:

- Duration of observation period following administration: 14 days
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight

Results and discussion

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LD50

Effect level:

1 900 mg/kg bw

Based on:

test mat.

95% CL:

> 1 620 - < 2 330

Effect levels 2

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

1 450 mg/kg bw

Based on:

test mat.

95% CL:

> 1 300 - < 1 580

Mortality:

Almost all deaths occurred the day administration was made (Day 1). Almost all animals observed that fell into the anesthetized state died. Only a few animals died on Day 2 or later.
Final mortality:
1, 0, 1, 3, 5, 7, 5, 8 and 7 out of 10 males died in the 0.74, 0.97, 1.15, 1.35, 1.55, 1.90, 2.22, 2.58 and 3.05 mg/kg bw dose groups, respectively.
0, 4, 8, 9, 9 and 10 out of 10 females died in the 1.11, 1.33, 1.56, 1.78, 2.18 and 2.53 mg/kg bw dose groups, respectively.
No animals died in the untreated control groups.

Clinical signs:

Symptoms such as inhibition of locomotor activity, staggering gait, and body ptosis occurred within 10 min after administration. Specific symptoms starting from limb paralysis and leading to anesthetized state occurred in a dose dependent manner several hours later. Almost all animals observed that fell into the anesthetized state died. Debilitation proceeded death in 3 of 37 dead males and one of 40 dead females.

Gross pathology:

Animals which died the day administration was made showed no marked changes other than congestion in the lungs, while those which died on Day 2 (both males and females) showed necrosis and bleeding spots sporadically in the stomach and slight change in color to yellow in the lungs. Autopsy conducted in surviving animals at the end of the study revealed adhesion in the anterior stomach (apical end) and liver (lateral left lobe) as well as adhesion of the spleen and diaphragm in many animals. However, females showed no such adhesion or any other abnormality.

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

When the substance was orally administered to rats, the LD50 was 1900 mg/kg bw in males and 1450 mg/kg in females.

Executive summary:

An acute oral toxicity test with the substance was conducted similar to the OECD TG 401 in the rat. The unchanged test substance was orally administered by gavage to Wistar rats. The tested concentrations lay in the range of 0.74 to 3.05 mg/kg bw (9 concentrations) for males and 1.11 to 2.53 mg/kg bw (6 concentrations) for females and 10 male and 10 female rats were treated per concentration. Untreated animals were included as control. Symptoms such as inhibition of locomotor activity, staggering gait, and body ptosis occurred within 10 min after administration. Specific symptoms starting from limb paralysis and leading to anesthetized state occurred in a dose dependent manner several hours later. Almost all deaths occurred the day administration was made (Day 1). Almost all animals observed that fell into the anesthetized state died. Only a few animals died on Day 2 or later. Debilitation preceeded death in 3 of 37 dead males and one of 40 dead females. Animals which died the day administration was made showed no marked changes other than congestion in the lungs, while those which died on Day 2 (both males and females) showed necrosis and bleeding spots sporadically in the stomach and slight change in colour to yellow in the lungs. Autopsy conducted in surviving animals at the end of the study revealed adhesion in the anterior stomach (apical end) and liver (lateral left lobe) as well as adhesion of the spleen and diaphragm in many animals. However, females showed no such adhesion or any other abnormality. The LD50 of the test material was determined to be 1900 mg/kg in males and 1450 mg/kg bw in females (mean: 1680 mg/kg), therefore in the range of 500 and 2000 mg/kg. Accordingly, the reaction product falls into acute toxicity hazard category 4 according to Regulation (EC) No 1272/2008 (CLP).