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Toxicological information

Acute Toxicity: inhalation

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Administrative data

Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1964-12-02 - 1965-01-15
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1965
Report Date:
1965

Materials and methods

Principles of method if other than guideline:
Method: Acute Inhalation Toxicity: Whole body exposure; described in reference
GLP compliance:
no
Test type:
standard acute method
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Test substance: other TS: Origin: Esso Research and Engineering Company, 2 Dec 1964,

Test animals

Species:
rat
Strain:
Wistar
Sex:
male
Details on test animals and environmental conditions:
TEST ORGANISMS: 
- Weight at study initiation: 200-225 grams
- Number of animals: 10
- Controls: yes

Administration / exposure

Route of administration:
inhalation: aerosol
Type of inhalation exposure:
whole body
Vehicle:
other: unchanged (no vehicle)
Details on inhalation exposure:
- Type of exposure: inhalation, aerosol

Analytical verification of test atmosphere concentrations:
not specified
Duration of exposure:
4 h
Concentrations:
- Concentrations: 5; 7; 10; 17.8 mg/l
No. of animals per sex per dose:
10 males
Control animals:
yes
Details on study design:
EXAMINATIONS: 
- Observations for deaths and toxic signs: 30 min intervals
- post observation: 14 days, daily
- gross pathology: at end of post observation period: all surviving animals
Statistics:
no data

Results and discussion

Effect levels
Sex:
male
Dose descriptor:
LC50
Effect level:
7 mg/L air
Exp. duration:
4 h
Remarks on result:
other: aerosol
Mortality:
- Number of deaths at each dose, time of death:     
5000 mg/m3: 4 hours = 0; 14 days = 1 death     
7000 mg/m3: 4 hours = 0; 14 days = 4 deaths
>= 10000 mg/m3: 4 hours = 10 deaths
LD50 confidence intervals: 5700-8600 mg/m3; slope function 1.27
Clinical signs:
other: 5000 mg/m3: none; higher doses: ataxia and coma, dyspnea, piloerection, depression,  decreased activity
Body weight:
no data
Gross pathology:
>= 10000 mg/m3:
- pulmonary congestion
Other findings:
no other findings

Any other information on results incl. tables

no remarks



 

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information Criteria used for interpretation of results: other: EC Directive 67/548/EEC
Conclusions:
Under the conditions of this study, the acute toxicity of isophorone after inhalative exposure in male rats is very low : the LC50 value was determined to be 7 mg/l.
Executive summary:

Groups of 10 male rats were exposed to isophorone for 4 hours by whole body exposure. The observation period was 2 weeks. At a concentration of 5000 mg/m3 one animal died after the observation period of 14 days. At a concentration of 7000 mg/m3 40 % of the rats died . At very high concentrations of 10000 and 17800 mg/m3 all animals died within 4 hours. Clinical signs were ataxia and coma, dyspnea, piloerection, depression and decreased activity at doses >= 5000 mg/m3. At necropsy of the high exposure concentrations, congestion of the lungs were observed.

The LC50 value was determined to be 7 mg/l. Therefore, under the conditions of this study the acute toxicity of isophorone after inhalative exposure in rats is very low.