Registration Dossier

Administrative data

Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Comparable to guideline study with acceptable restrictions. Restrictions: no GLP study, only males, LC50 estimated

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1992
Report Date:
1992

Materials and methods

Principles of method if other than guideline:
Estimation of an inhalative LC50 value
GLP compliance:
not specified
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent

Test animals

Species:
rat
Strain:
other: ChR-CD
Sex:
male
Details on test animals and environmental conditions:
initial bw 243-304 g

Administration / exposure

Route of administration:
inhalation: vapour
Type of inhalation exposure:
not specified
Vehicle:
other: no data
Details on inhalation exposure:
Tested concentrations: nominal 300, 625, 1250, 2500 or 5000 ppm (0.975, 2.03, 4.06, 8.1, 16.2 mg/l; 1 ppm = 3.25 mg/m3, calculated for normal pressure and 20°C); TS heated in a T-tube to ca. 100-125°C to insure complete vaporization; dry air stream carried the vapour to 8-liter bell jar containing 4 rats; post exposure observation period 14 d
Duration of exposure:
4 h
Concentrations:
975, 2030, 4060, 8100, 16200 mg/m³ (300, 625, 1250, 2500, or 5000 ppm)
No. of animals per sex per dose:
4
Control animals:
not specified

Results and discussion

Effect levels
Sex:
male
Dose descriptor:
LC50
Effect level:
ca. 2 mg/L air
Exp. duration:
4 h
Mortality:
4/4 rats died at concentrations >=1250 ppm (died during exposure in high dose groups or found dead 1 d after exposure at 1250 ppm); 2/4 rats died one d after exposure at 625 ppm; all rats survived in the low dose group. LC50 estimated (no calculation given by the authors).
Clinical signs:
During exposure of lethal concentrations rats showed red ears, inactivity, hyperpnea followed by dyspnea, pumping respiration, ruffled fur, fluid around the nose, discomfort, incoordination, tremor, convulsions, prolonged extension of body and limbs; after exposure rats showed weakness, prostration and hyperpnea. One rat at the 625 ppm level exhibited partial paralysis of the hind legs for 1-6 d and no complete recovery thereafter; survivors in this dose group showed large initial weight loss.
Gross pathology:
Rats that died during exposure showed congestion of various organs (vascular collapse). Edema and emphysema of the lungs in rats found dead the day after exposure. At 2500 ppm 2 rats showed yellow staining of liver sinusoids. No lesions in survivors.

Applicant's summary and conclusion

Conclusions:
Findings indicate effects on central nervous system, respiratory and circulatory systems and possibly on the liver.