Bromochloromethane

Acute Toxicity: inhalation

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 guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OTS 798.1150 (Acute inhalation toxicity)

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Bromochloromethane

EC Number:

200-826-3

EC Name:

Bromochloromethane

Cas Number:

74-97-5

Molecular formula:

CH2BrCl

IUPAC Name:

bromo(chloro)methane

Constituent 2

Reference substance name:

2008263

IUPAC Name:

2008263

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system 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:

other: 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, noi

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.