Registration Dossier

Administrative data

Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
17 Sep 1997 -19 Nov 1997
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1998

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 403 (Acute Inhalation Toxicity)
Qualifier:
according to
Guideline:
EPA OTS 798.1150 (Acute inhalation toxicity)
GLP compliance:
yes (incl. certificate)
Test type:
standard acute method
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River France, 59 rune de la Paix, 76140 SAINT-AUBIX-LES ELBEUF (FRANCE).
- Age at study initiation: 8-10 weeks
- Weight at study initiation: The males weight ware: 283 to 294 g. The females weight were: 219 to 248 g.
- 5 days of acclimatisation before start of study.
-Free access of water and food.
- Housing: Solid-floor polypropylene cages

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 ± 2 ºC
- Humidity (%): 55±15 %
- Air changes (per hr): at least 15 changes per hr.
- Photoperiod (hrs dark / hrs light): 12 / 12

Administration / exposure

Route of administration:
inhalation: vapour
Type of inhalation exposure:
nose only
Vehicle:
air
Details on inhalation exposure:
TYPE OF INHALATION EXPOSURE: Nose only

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Incubation chamber with a capacity of 30 liters
- Method of holding animals in test chamber: each rat was held in tapered tube which was fitted onto a tier of the exposure chamber
- System of generating particulates/aerosols:
- Temperature, humidity in air chamber: 21 ± 2 ºC, 55±15 % humidity.
- Air change rate: at least 15 air changes per hour.
- Method of particle size determination: NDA
- Treatment of exhaust air: NDA

TEST ATMOSPHERE
- Brief description of analytical method used: an electronic termometer/humidity meter measured every 30 min. in the 4 hours exposure.
- Samples taken from breathing zone: pumping known amount into a glass containing acetone.
Analytical verification of test atmosphere concentrations:
yes
Remarks:
by gas chromatography.
Duration of exposure:
4 h
Concentrations:
Exposure chamber mean achieved concerntration was 38.6 mg/l
No. of animals per sex per dose:
5 males and 5 females
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Clinical observations made immediately on removal from the restraining tubes at the end of exposure,
1 hour after termination of exposure and at least once a day for 14 days. Body weights recorded on days: day of exposure, 7,14 or at death.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, macroscopic examination of respiratory tract.
Statistics:
NDA

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LC50
Effect level:
> 38.6 mg/L air
Based on:
test mat.
Exp. duration:
4 h
Mortality:
One female was found dead on completion of exposure and one male was found dead after 2 hr and 21 min after exposure.
Clinical signs:
Clinical signs observed included wet fur and increased or decreased respiratory rate and laboured respirations and fasciculations. 8 survivors were comatose and hypothermicm hunched posture, loss of righting reflex, lethargy, pilo-erection, ataxia, noisy respiration and diuresis. All signs had
disappeared by day 2 to 4.
Body weight:
During week 1- one male showed no gain in bodyweight and possible reduction in bodyweight gain was noted in several other survivors.
Noraml bodyweight gain was noted during week 2.
Gross pathology:
Lung abnormalities were found. they included haemorrhage, swelling, abnormal darkening, dark patches, pale patches and dark foci
Other findings:
N/A

Applicant's summary and conclusion

Interpretation of results:
practically nontoxic
Remarks:
Migrated information Criteria used for interpretation of results: OECD GHS
Conclusions:
The acute inhalation LC50 of the test substance Bromochloromethane was greater than 38.6 mg/l.
Executive summary:

An acute inhalation toxicity was perfomed on 5 males and 5 female Sprague Dawley rats with mean achieved concentration of 38.6 mg/l. The test followed OECD guideline 403 and was performed to GLP standard.

Only 2 mortality cases were observed. Therefore, the LC50 of the test substance Bromochloromethane was determined to be greater than 38.6 mg/l.