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Acute Toxicity: inhalation

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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:
data from handbook or collection of data
Justification for type of information:
Data is from authoritative database.

Data source

Referenceopen allclose all

Reference Type:
other: authoritative database
Title:
Acute Inhalation toxicity - LC50
Author:
U.S. National Library of Medicine
Year:
2012
Bibliographic source:
HSDB
Reference Type:
other: study report
Title:
SIDS INITIAL ASSESSMENT PROFILE
Author:
US/ICCA
Year:
2006
Bibliographic source:
SIAM 23, 17-20 October 2006

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: As mentioned below
Principles of method if other than guideline:
Acute Inhalation toxicity of the given test chemical in rat.
GLP compliance:
not specified
Test type:
other: not specified
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- IUPAC Name: Ethyl cyanoacetate
- Common Name: ECYA
- InChI: 1S/C5H7NO2/c1-2-8-5(7)3-4-6/h2-3H2,1H3
- Smiles: C(CC#N)(OCC)=O
- Molecular formula:C5H7NO2
- Molecular weight :113.1153 g/mol
- Substance type:Organic
- Physical state:Liquid - colorless mild pleasant odour
- Purity: 99.7%
- Impurities (identity and concentrations):0.3%

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River UK
- Age at study initiation: 6 to 8 weeks
- Weight at study initiation: ca. 200 g
- Housing: Animals were kept in cages.
- Diet (e.g. ad libitum): Food was provided
- Water (e.g. ad libitum): water was provieded

Administration / exposure

Route of administration:
inhalation: aerosol
Type of inhalation exposure:
whole body
Vehicle:
clean air
Mass median aerodynamic diameter (MMAD):
5.8 µm
Geometric standard deviation (GSD):
2.23
Remark on MMAD/GSD:
Sampling with a Marple cascade impactor 35 minutes after the start of exposure.
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: exposure chamber
- Exposure chamber volume: 120 L
- Method of holding animals in test chamber: Animals were held in 10 separate animal compartments.
- Source and rate of air: Respirable aerosol in clean dried air produced by aerosol generator (equilibration period 9 min),
- Temperature, humidity, pressure in air chamber: supply pressure 15 l/min, flow rate in the exposure chamber: 0.8 ml/min per pump, total flow rate 1.6 ml/min.

TEST ATMOSPHERE (if not tabulated)
- Particle size distribution:
- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.): mass median aerodynamic diameter (MMAD): 5.8 µm, geometric standard deviation: 2.23, 59.5% in the respirable range (< 7 µm).

CLASS METHOD (if applicable)
- Rationale for the selection of the starting concentration: Analytical determination, sampling through a gas absorption trap, 3 samples were taken during the exposure period
Analytical verification of test atmosphere concentrations:
not specified
Duration of exposure:
1 h
Remarks on duration:
not specified
Concentrations:
7.38 mg/l +- 0.131 (nominal 58 mg/l or 7380 mg/m3)
No. of animals per sex per dose:
5 males, 5 females per group
Control animals:
yes
Remarks:
clean air only
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Clinical signs: continuously during exposure, twice daily during the observation period.
Body weights: daily. Food and water consumption per cage.
- Necropsy of survivors performed: yes
- Other examinations performed: Macroscopic organ examination at necropsy, lung weights.
Statistics:
not specified

Results and discussion

Preliminary study:
not specified
Effect levels
Sex:
male/female
Dose descriptor:
LC50
Effect level:
> 7 380 mg/m³ air (analytical)
Based on:
test mat.
Exp. duration:
1 h
Remarks on result:
other: No mortality was observed
Mortality:
No mortality was observed at 7380 mg/m3.
Clinical signs:
During observation period, immediately after removal from the exposure chamber: exaggerated respiratory movements and matted fur (all rats), wet fur around the snout and jaws (2 males) and clear discharge from the eyes (3 females), brown staining around the snout and jaws (1 female) were observed. All symptoms were reversible within 24 hours.
Body weight:
Slightly reduced body weight and food consumption on day 1, thereafter comparable to control. Water consumption not affected.
Gross pathology:
At necropsy there were no macroscopic abnormalities in the rats.
Other findings:
Lung to body weight ratio were comparable between test and control animals.

Applicant's summary and conclusion

Interpretation of results:
other: Not classified
Conclusions:
The acute inhalation toxicity dose (LC50) value was considered to be >7380 mg/m3, when 10 male and female Sprague-Dawley rats were treated with test chemical via inhalation route by aerosol to whole body exposure for 1 hour.
Executive summary:

Acute inhalation toxicity study of test chemical was conducted in 10 male and female Sprague-Dawley rats at the dose concentration of 7380 mg/m3 (7.38 mg/l). The exposure was given towhole body, respirable aerosol in clean dried air produced by aerosol generator (equilibration period 9 min), and exposure chamber 120 l with 10 separate animal compartments. The control animals received clean air only. Animals were observed for - clinical signs: continuously during exposure, twice daily during the observation period; body weights: daily; Food and water consumption per cage. Necropsy of survivors was performed. Macroscopic organ examination at necropsy and lung weights was done. No mortality was observed at 7380 mg/m3.During observation period, immediately after removal from the exposure chamber: exaggerated respiratory movements and matted fur (all rats), wet fur around the snout and jaws (2 males) and clear discharge from the eyes (3 females), brown staining around the snout and jaws (1 female) were observed. All symptoms were reversible within 24 hours. Slightly reduced body weight and food consumption on day 1, thereafter comparable to control. Water consumption not affected. At necropsy there were no macroscopic abnormalities in the rats. Lung to body weight ratio were comparable between test and control animals. Therefore, LC50 value was considered to be >7380 mg/m3, when 10 male and female Sprague-Dawley rats were treated with test chemical via inhalation route by aerosol to whole body exposure for 1 hour.