2,6-Octadienal, 3,7-dimethyl-, acid-isomerized

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22.02.-16.03.1984

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1984

Report date:

1984

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

no

GLP compliance:

yes

Test type:

fixed dose procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2,6-Octadienal, 3,7-dimethyl-, acid-isomerized

EC Number:

291-768-8

EC Name:

2,6-Octadienal, 3,7-dimethyl-, acid-isomerized

Cas Number:

90480-35-6

IUPAC Name:

1-methyl-4-(propan-2-yl)benzene; ethanol

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 4 - 6 weeks
- Weight at study initiation: 87 - 150g for males and 86 - 136g for females
- Fasting period before study: overnight
- Housing: 5 in polypropylene cages with sawdust bedding.
- Diet: ad libitum; standard laboratory rodent diet (Rat and Mouse Expanded Diet No. 1, supplied by Special Diet Services Ltd., Witham, Essex)
- Water: ad libitum; tap water
- Acclimation period: minimum 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.5 +/- 3.5
- Humidity (%): 45 - 55
- Air changes (per hr): 10
- Photoperiod (hrs dark / hrs light): 12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

- Dose volume: 5.62 mL/kg
- Gavage: metal cannula attached to a graduated syring
- Dose perparation: calculated according to animals bodyweight at the time of dosing

Doses:

5000 mg/kg

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

RANGE FINDING STUDY
- goal: establish dosing regimen
- animals: 2 male and 2 female
- dose: 5000 mg/kg
- dose volume: 5.62 mL/kg
- observation: daily
- duration: 5 days or until all evidence of toxicity had subsided, whichever was the longer

MAIN STUDY
- Duration of observation period following administration: 14 days
- Frequency of observations: 0.5, 1, 2, 3, 4 and 5 hours after dosing and once daily
- Weighing: days 0, 7 and 14
- Necropsy of survivors performed: yes
- Other examinations performed: macroscopic post mortem examination

Results and discussion

Preliminary study:

No animals died in the Range Finding Study. A dose level of 5000 mg/kg was selected for the Main Study.

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

3 animals died during the course of the study: 1 male and 1 female on day 1 and another male on day 2

Clinical signs:

other: Signs of reaction to treatment observed shortly after dosing in all treated rats included pilo-erection, and abnormal body carriage (hunched posture), lethargy, a decreased respiratory rate and ptosis. A comatose-like condition was observed in one male ra

Gross pathology:

Mortalities occurred within one to two days of dosing. Necropsy revealed distension and haemorrhage of the stomach.
Necropsy of the survivors at termination of the study did not reveal any macroscopic abnormalities.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The LD50 of the test item is > 5000 mg/kg bw. The substance is not acute toxic and should not be classified.

Executive summary:

In the current study the oral acute toxicity of the test item was assessed in an OECD 401 study. The study was according to GLP.

5 male and 5 female rats were given 5000 mg/kg bw once and were observed for 14 days. The dose was determined in a range finding study with 2 males and 2 females. No animals died in the range finding study.

In the main study 3 animals died during the study. Necropsy of the animals that died during the study revealed distension and haemorrhage of the stomach. Slightly depressed bodyweight gains were recorded for surviving male rats during the first week of observation. Bodyweight gains of the remaining rats were within normal range throughout the two-week observation period.

Clinical signs observed shortly after dosing in all treated rats included pilo-erection, hunched posture, lethargy, a decreased respiratory rate and ptosis. A comatose-like condition was observed in one male rat prior to death and wet fur was seen in two males. Recovery of the survivors, as judged by external appearance and behaviour, was complete by day 6. Necropsy of the survivors at termination of the study did not reveal any macroscopic abnormalities.

Based on these observations the LD50 is > 5000 mg/kg bw. The substance is not acute toxic and should not be classified.