Potassium perchlorate

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Animals were exposed to a pyrotechnically generated atmosphere, the relevance of this to the submission substance is unclear.

Data source

Reference

Reference Type:

publication

Title:

Evaluation of the Respiratory Tract after Acute Exposure to a Pyrotechnically Generated Aerosol Fire Suppressant

Author:

Smith EA, Kimmel EC, English JH, Bowen LE, Reboulet JE & Carpenter RL

Year:

1997

Bibliographic source:

Journal of Applied Toxicology 17 (2): 95-103

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Fischer 344 rats (250 -300g) were exposed to the resulting aerosols from the pyrolysis of Spectrex Fire Extinguishant (SFE) Formulation A, a pyrotechnically generated aerosol fire suppressant, at a loading 50 or 80 g/m3 air for 15 or 60 minutes.
Exposures were conducted in a 700 L whole-body inhalation chamber, under static conditions. The chamber atmosphere was analysed for mass aerosol concentration and particle size distribution. Clinical observations were recorded throughout the exposure period. The rats were terminated 1, 6, 24 hours or 7 or 14 days post-exposure and subjected to histopathological examination, enzyme analysis and determination of wet and dry lung weights.

GLP compliance:

no

Test type:

other:

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Spectrix Fire Extinguishant Formulation A

IUPAC Name:

Spectrix Fire Extinguishant Formulation A

Test material form:

other: dry-powder fire retardant

Details on test material:

During fire suppression standard procedures result in unintentional release of fluorocarbons. Due to the destructive effect of fluorocarbons on atmospheric ozone, CFCs and halocarbons are being phased out and replacement fire suppressants based on dry-powder aerosols are being developed.
Spectrex Fire Extinguishant (SFE) is one of the pyrotechnically generated aerosols comprising primarily potassium perchlorate, which generates an aerosol of potassium chloride on decomposition.
The aerosol particles produced by the pyrolisation process are typically of a respirable size (typically 1-10 µm). Such particles are inhalable and can penetrate deep into the tracheobronchial tree and alveoli.

Test animals

Species:

rat

Strain:

Fischer 344

Sex:

not specified

Details on test animals or test system and environmental conditions:

Fischer 344 rats (250 -300g)

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

whole body

Details on inhalation exposure:

The rats were exposed to the resulting aerosols from the pyrolysis of Spectrex Fire Extinguishant (SFE) Formulation A, a pyrotechnically generated aerosol fire suppressant, at a loading 50 or 80 g/m3 air for 15 or 60 minutes.
Exposures were conducted in a 700 L whole-body inhalation chamber, under static conditions.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

>= 15 - <= 60 min

Concentrations:

50 or 80 g/m3 air

Details on study design:

The rats were terminated 1, 6, 24 hours or 7 or 14 days post-exposure.

Results and discussion

Effect levels

Sex:

not specified

Dose descriptor:

LC50

Effect level:

> 80 mg/m³ air

Based on:

test mat.

Exp. duration:

60 min

Remarks on result:

other: No deaths occurred at the highest exposure concentration

Mortality:

No deaths occurred.

Clinical signs:

other: Clinical signs of reaction to treatment included dyspnoea, coughing, lack of coordination and lethargy. Signs became more pronounced as the exposure duration and dose loading increased.

Gross pathology:

Macroscopic examination revealed no lesions in the trachea, lung, heart or organs in the abdominal cavity.
Animals exposed to an SFE loading of 80 g/m3 for 60 minutes developed reversible pulmonary oedema and olfactory necrosis. Protein concentrations in the bronchoalveolar lavage increased but no changes were evident in enzyme levels. Wet and dry lung weights showed no differences between treated and control groups.

Applicant's summary and conclusion

Interpretation of results:

other: not adequate for classification purposes

Conclusions:

The LC50 of the resulting aerosols from the pyrolysis of Spectrex Fire Extinguishant (SFE) Formulation A, a pyrotechnically generated aerosol fire suppressant is greater than 80 g/m3 air after 60 minutes exposure.

Executive summary:

Fischer 344 rats (250 -300g) were exposed to the resulting aerosols from the pyrolysis of Spectrex Fire Extinguishant (SFE) Formulation A, a pyrotechnically generated aerosol fire suppressant, at a loading 50 or 80 g/m3 air for 15 or 60 minutes.

Exposures were conducted in a 700 L whole-body inhalation chamber, under static conditions. The chamber atmosphere was analysed for mass aerosol concentration and particle size distribution. Clinical observations were recorded throughout the exposure period. The rats were terminated 1, 6, 24 hours or 7 or 14 days post-exposure and subjected to histopathological examination, enzyme analysis and determination of wet and dry lung weights.

No deaths occurred. Clinical signs of reaction to treatment included dyspnoea, coughing, lack of coordination and lethargy. Signs became more pronounced as the exposure duration and dose loading increased. Macroscopic examination revealed no lesions in the trachea, lung, heart or organs in the abdominal cavity.

Animals exposed to an SFE loading of 80 g/m3 for 60 minutes developed reversible pulmonary oedema and olfactory necrosis. Protein concentrations in the bronchoalveolar lavage increased but no changes were evident in enzyme levels. Wet and dry lung weights showed no differences between treated and control groups.