Hexabromocyclododecane

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Not reported. Test material was received 12 July 1977, study report was finalised 7 December 1977

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted in accordance with generally accepted scientific principles, possibly with incomplete reporting or methodological deficiencies, which do not affect the quality of the relevant results.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1977

Report date:

1977

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Five male and 5 female Charles River CD rats, weighing from 232 to 258 grams, were used in the study of the compound. The rats were housed individually in wire-mesh cages and were maintained in a temperature and humidity controlled room throughout the pre-exposure and post exposure periods. Purina Laboratory Chow and water were supplied ad libitum, except during exposure in the chamber.

The rats were caged in groups of 2 or 3 by sex in 4 wire-mesh exposure cages. The cages were placed in a 160-liter cubical stainless steel, glass chamber. A constant chamber airflow of 7 liters per minute was maintained by means of a rotary centrifugal air pump located at the exhaust side of the chamber. The chamber exhaust was filtered with an activated charcoal filter and a Cambridge Absolute® filter before being discharged outside of the laboratory.

The dust atmosphere of the compound was generated by dispersing the powder at a calculated rate with a specially constructed dust generator located near the chamber air inlet at the top of the exposure chamber. This dust generator consisted of a revolving plate with calibrated "cups" for transporting a known quantity of powder per unit of time from a reservoir to a "blowhole". At the "blowhole" the powders in a "cup" were dispersed into the chamber by a jet of air blowing at the rate of 2 liters per minute. The actual quantity of powder disseminated was determined by weighing the quantity of powder in the reservoir before and after the experiment. The concentration of the dusts in the chamber atmosphere was calculated from the ratio of the rates of powder dissemination to the total chamber airflow (the volume of air ejected from the dust generator plus the volume of make-up air).

Observations for ocular and nasal irritation, respiratory distress and mortality were made during and immediately following the 4 hour exposure period and daily thereafter for 14 days. Individual body weights were recorded prior to the 4 hour exposure and periodically thereafter in order to detect any transient effects following the exposure.

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Hexabromocyclododecane

EC Number:

247-148-4

EC Name:

Hexabromocyclododecane

Cas Number:

25637-99-4

Molecular formula:

C12H18Br6

IUPAC Name:

(1S,2S,5S,6S,9S,10S)-1,2,5,6,9,10-hexabromocyclododecane

Details on test material:

Test material identified as 'Firemaster 100 Lot 53 77.902' and was received as a fine white powder.

Test animals

Species:

rat

Strain:

other: Charles river CD rats

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source:
Not reported.

- Age at study initiation:
Not reported.

- Weight at study initiation:
232-258 grams

- Fasting period before study:
Not reported.

- Housing:
individually in Wire-mesh cages and were maintained in a temperature and humidity controlled room throughout the pre-exposure and post exposure periods.

- Diet (e.g. ad libitum):
Purina Laboratory Chow was supplied ad libitum, except during exposure in the chamber.

- Water (e.g. ad libitum):
adlibitum

- Acclimation period:
Not reported.

ENVIRONMENTAL CONDITIONS
- Temperature (°C):
Not reported.

- Humidity (%):
Not reported.

- Air changes (per hr):
Not reported.

- Photoperiod (hrs dark / hrs light):
Not reported.

IN-LIFE DATES: From: Day 1 To: Day 15

Administration / exposure

Route of administration:

inhalation: dust

Type of inhalation exposure:

whole body

Vehicle:

other: unchanged (no vehicle)

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus:
The rats were caged in groups of 2 or 3 by sex in 4 wire-mesh exposure cages. The cages were placed in a 160-liter cubical stainless steel, glass chamber. A constant chamber airflow of 7 liters per minute was maintained by means of a rotary centrifugal air pump located at the exhaust side of the chamber.

- Exposure chamber volume:
160 L

- Method of holding animals in test chamber:
Wire-mesh cages

- Source and rate of air:
Rotary centrifugal air pump located at the exhaust side of the chamber.

- Method of conditioning air:
Not reported.

- System of generating particulates/aerosols:
The dust atmosphere of the compound was generated by dispersing the powder at a calculated rate with a specially constructed dust generator located near the chamber air inlet at the top of the exposure chamber. This dust generator consisted of a revolving plate with calibrated "cups" for transporting a known quantity of powder per unit of time from a reservoir to a "blowhole". At the "blowhole" the powders in a "cup" were dispersed into the chamber by a jet of air blowing at the rate of 2 liters per minute. The actual quantity of powder disseminated was determined by weighing the quantity of powder in the reservoir before and after the experiment. The concentration of the dusts in the chamber atmosphere was calculated from the ratio of the rates of powder dissemination to the total chamber airflow (the volume of air ejected from the dust generator plus the volume of make-up air).

- Method of particle size determination:
Not reported.

- Treatment of exhaust air:
The chamber exhaust was filtered with an activated charcoal filter and a Cambridge Absolute® filter before being discharged outside of the laboratory.

- Temperature, humidity, pressure in air chamber:
Not reported.

TEST ATMOSPHERE
- Brief description of analytical method used:
Not reported.

- Samples taken from breathing zone:
Not reported.

VEHICLE
Not applicable.

TEST ATMOSPHERE (if not tabulated)
- Particle size distribution:
Not reported.

- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.):
Not reported.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting concentration:
Not reported.

Analytical verification of test atmosphere concentrations:

not specified

Duration of exposure:

4 h

Concentrations:

202.14 mg/l

No. of animals per sex per dose:

5 male and 5 female

Control animals:

no

Details on study design:

- Duration of observation period following administration:
14 days

- Frequency of observations and weighing:
Observations for ocular and nasal irritation, respiratory distress and mortality were made during and immediately following the 4 hour exposure period and daily thereafter for 14 days. Individual body weights were recorded prior to the 4 hour exposure and period¬ically thereafter in order to detect any transient effects following the exposure.

- Necropsy of survivors performed:
no

Statistics:

Not reported.

Results and discussion

Preliminary study:

Not applicable.

Effect levels

Sex:

male/female

Dose descriptor:

discriminating conc.

Effect level:

> 202.14 mg/L air (nominal)

Exp. duration:

4 h

Remarks on result:

other: 95% CL not reported

Mortality:

No death occurred during or after the 4 hour exposure to the experimental atmosphere.

Clinical signs:

other: The immediate response of the rats to the experimental atmosphere was an increase of activity in preening. After 10 minutes of exposure, the rats settled down. From 1 hour and 30 minutes after the initiation of exposure to the end of the 4 hour period, th

Body weight:

All rats continued to gain body weight after the exposure.

Individual Body Weights of Rats Exposed to Firemaster 100.
Dosage Individual Sex Control 7-Day 14-Day
Level Rat Number Weight Weight Weight
(grams). (grams). (grams).
202.1428 68690 Male 252 310 360
mg/l 68692 Male 242 269 301
68696 Male 246 260 280
68698 Male 251 259 261
68699 Male 242 280 310
68691 Female 258 321 362
68693 Female 254 303 350
68695 Female 239 251 272
68697 Female 238 240 243
68699 Female 232 244 255

Gross pathology:

Not applicable.

Other findings:

None reported.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Inhalation exposure of rats to the dust atmosphere of Firemaster 100 resulted in slight dyspnea during exposure. However, no latent adverse effect was observed post exposure. Based upon the experimental results, it is concluded that a single 4 hour inhalation exposure to the dusts would not likely be harmful.

Executive summary:

Five male and 5 female Charles River CD rats were used in the study of the compound. The rats were housed individually in wire-mesh cages and were maintained in a temperature and humidity controlled room throughout the pre-exposure and post exposure periods. The rats were caged in groups of 2 or 3 by sex in 4 wire-mesh exposure cages. The cages were placed in a 160-liter cubical stainless steel, glass chamber. A constant chamber air flow of 7 liters per minute was maintained by means of a rotary centrifugal air pump located at the exhaust side of the chamber. The exposure period was 4 hours. The chamber exhaust was filtered with an activated charcoal filter and a Cambridge Absolute® filter before being discharged outside of the laboratory.

The total chamber airflow was 7 liters per minute and the chamber dust concentration was calculated to be 202.14 mg/L. The chamber atmosphere was extremely dusty.

Inhalation exposure of rats to the dust atmosphere of Firemaster 100 resulted in slight dyspnea during exposure. However, no latent adverse effect was observed post exposure.

Based upon the experimental results, it is concluded that a single 4 hour inhalation exposure to the dusts would not likely be harmful.