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Administrative data

acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Between 30-04-1993 and 3-11-1993
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Study conducted in compliance with agreed protocols, with no deviations from standard test guidelines and no methodological deficiences, which do not affect the quality of the relevant results. The study report was conclusive, done to a valid guideline and the study was conducted under GLP conditions.

Data source

Reference Type:
study report

Materials and methods

Test guideline
according to guideline
OECD Guideline 401 (Acute Oral Toxicity)
GLP compliance:
Test type:
standard acute method
Limit test:

Test material

Constituent 1
Reference substance name:
n-Hexyl bromide
n-Hexyl bromide
Test material form:
other: liquid
Details on test material:
Colourless liquid
Glass flask containing 53 g
Date of receipt: 07-05-1993
Purity > 98.5 %
Storage conditions : at room temperature, away from light

Test animals

Details on test animals or test system and environmental conditions:
Breeder: IFFA Crédo, 69210 L'ARBRESLE, FRANCE
Number and sex: one group of ten animals (5 males and 5 females)
On the day of the treatment, the animals were approximately 6 weeks old, and had a mean body weight of 176 ± 5 g for the males and 14 ± 6 g for the females.
Acclimatization: at least 5 days before the beginning of the study.
The animals were identified individually by earmarks or ear-notches.
During the acclimatization period and during the main test, the conditions in the animal room were as follow:
temperature: 22 ± 3°C
relative humidity: 50 ± 20 %
light/darkness cycle: 12 h/ 12 h
ventilation: about 13 cycles/hour of filtered, non-recycled air.
The temperature and relative humidity were recorded continuously and records retained.
The housing conditions (temperature, relative humidity, light/dark cycle and ventilation) were checked monthly.
The animals were housed in polycarbonate cages (48 x 27 x 20 cm) covered with a stainless steel lid. Each cage contained 4 to 7 animals of the same sex during the acclimatization period and 5 rats of the same sex during the treatment period. Each cage contained graded, dust-free sawdust.
Bacteriological analysis of the sawdust and detection of possible contaminants (pesticides, heavy metals) are performed periodically.
All the animals had free access to AO4 C pelleted diet.
Each batch of food was analysed (composition and contaminants) by the supplier.
Drinking water filtered by a F.G. Millipore membrane (0.22 micron) was contained in bottles.
Bacteriological and chemical analysis of the water and detection of possible contaminants (pesticides, heavy metals and nitrosamines) ae performed periodically.
There were no contaminants in the diet, water or sawdust at level likely to have influenced the outcome of the study.

Administration / exposure

Route of administration:
oral: gavage
unchanged (no vehicle)
Details on oral exposure:
The animals were fasted for an overnight period of approximately 18 hours before dosing, but had free access to water.
Food was given approximately 4 hours after administration of the test substance.
As the test substance was anticipated to be non toxic at 2000 mg/kg, a limit test was performed by administrating 2000 mg/kg of the test substance to a group of 10 animals (5 males and 5 females). The test substance was adminitrated in its original form taking into consideration that the specific gravity was 1.17.
No. of animals per sex per dose:
2000 mg/kg of the test substance to 5 males and 5 females
Control animals:
Details on study design:
The animals were observed frequently during the hours following administartion of the test substance, for detection of possible treatment-related clinical signs. Observation of the animals wa made at least once a day for a period of 14 days, to determine wether any of the clinical signs were reversible or not.
The animals were checked frequently during the hours followig administartion of the test substance for mortality or signs of morbidity, then at least twice a day thereafter. The time of any deaths was recorded individually, in terms of the number of hours or days after dosing.
The animals were weighted individually just before administration of the test substance, and then on days 5, 8 and 15 for the surviving animals.
The body weight gain of the treated animals was compared to a reference curve of C.I.T. control animals with the same initial weight.

Results and discussion

Effect levels
Dose descriptor:
Effect level:
>= 2 000 mg/kg bw
Based on:
test mat.
At 2000 mg/kg the mortality rate was 10 % (one female found dead on day 8)
Clinical signs:
other: At 2000 mg/kg hypoactivity, sedation and piloerection were observed within 4 hours post-treatment. On day 2, sedation and piloerection in 2 animals and hypoactivity in 8 animals were noted. Clinical signs appeared within 15 minutes of treatment and were r
Gross pathology:
Macroscopic examination of the main organs of the animal found dead during the study or those sacrified at the end of the study revealed no apparent abnormalities.
Other findings:

Applicant's summary and conclusion

Interpretation of results:
not classified
Migrated information Criteria used for interpretation of results: EU
Under the experimental conditions, the LD50 of the test substance n-Hexyl bromide when administrated by oral route in rats was higher than 2000 mg/kg
Executive summary:

At 2000 mg/kg, for 9 of the 10 animals, a marked decreased in spontaneous activity and piloerection within 4 hours following treatment then hypoactivity from day 2 were observed. The surviving animals had fully recovered on day 5 (8 animals) or on day 7 (one animal).

Mortality rate at 2000 mg/kg was 10 % (one female found dead on day 8).

The rate of body weight gain of the surviving animals had slowed down between days 1 and 5. The body weight gain returned to normal thereafter.

A macroscopic examination revealed no abnormalities in the animal found dead during the study or those sacrified et the end of the study.