Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1999
Report date:
1999

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Deviations:
no
GLP compliance:
yes
Test type:
acute toxic class method
Limit test:
no

Test material

Constituent 1
Chemical structure
Reference substance name:
Thioacetic acid
EC Number:
208-063-8
EC Name:
Thioacetic acid
Cas Number:
507-09-5
Molecular formula:
C2H4OS
IUPAC Name:
ethanethioic S-acid
Test material form:
other: liquid
Details on test material:
- Name of test material (as cited in study report): Thioacetic acid
- batch AOGHJU,
- purity 99.58%.

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Iffa Crédo, 69210 L'Arbresle, France.
- Age at study initiation: approximately 6 weeks old
- Weight at study initiation: 176 ± 4 g for the males and 143 ± 6 g for the females
- Fasting period before study:
- Housing: in polycarbonate cages (48 cm x 27 cm x 20 cm). Each cage contained one to seven animals of the same sex during the acclimatization period and five rats of the same sex during the treatment period
- Diet/ A04 C pelleted diet ad libitum
- Water: Drinking water filtered by a FG Millipore membrane (0.22 micron) was provided ad libitum.
- Acclimation period: at !east 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 ± 2
- Humidity (%): 30 to 70
- Air changes (per hr): 12
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
corn oil
Details on oral exposure:
MAXIMUM DOSE VOLUME APPLIED: 10 ml/kg
Doses:
200, 350, 500 and 1000 mg/kg
No. of animals per sex per dose:
4 groups of five males or five females were used
Control animals:
no
Details on study design:
Clinical signs, mortality and body weight gain were checked for a period of up to 14 days following the single administration of the test substance. All animals were subjected to necropsy.
Statistics:
None

Results and discussion

Effect levels
Sex:
female
Dose descriptor:
LD50
Effect level:
200 - 350 mg/kg bw
Mortality:
At the 200 mg/kg dose-level, no mortality were recorded.
At the 350, 500 and 1000 mg/kg dose-levels, all animals died within 24  hours following treatment. 
Clinical signs:
At the 200 mg/kg dose-level, no clinical signs were recorded.
At the 350, 500 and 1000 mg/kg dose-levels, hypoactivity or sedation, piloerection, dyspnea, lateral recumbency, tonic-clonic convulsions and hypersalivation were the clinical signs observed prior to death.
Body weight:
The body weight gain of the surviving animals given 200 mg/kg was not affected by treatment with the test substance.
Gross pathology:
At necropsy, a whitish coloration of the stomach and intestines was noted in the animals given 1000 mg/kg. No apparent abnormalities were observed in the other animals.

Applicant's summary and conclusion

Interpretation of results:
Toxicity Category IV
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
The oral LD50 of the test substance THIOACETIC ACID is comprised between 200 and 350 mg/kg, in female rats.
Executive summary:

The acute oral toxicity of the THIOACETIC ACID was evaluated in rats according to OECD (No. 401, 24th February 1987) and EC (92/69/EEC, B.l, 31st July 1992) guidelines. The study was conducted  in compliance with the principles of Good  Laboratory Practice Regulations. The test substance was administered by oral route (gavage) to groups of five male or five female fasted Sprague-Dawley rats. The test substance was prepared in corn oil and administered to the animals under a volume of 10 ml/kg. The study design was as follows:

 

Dose

(mg/kg)

Vehicle

Volume (ml/kg)

Male

Female

200

corn oil

10

 

5

350

corn oil

10

 

5

500

corn oil

10

 

5

1000

corn oil

10

5

 

 

Clinical signs, mortality and body weight gain were checked for a period of up to 14 days following the single administration of the test substance. All animals were subjected to necropsy.

At the 200 mg/kg dose-level, no clinical signs and no mortality were recorded. At the 350, 500 and 1000 mg/kg dose-levels, all animals died within 24 hours following treatment. Hypoactivity or sedation, piloerection, dyspnea, lateral recumbency, tonic-clonic convulsions and hypersalivation were the clinical signs observed prior to death. The body weight gain of the surviving animals given 200 mg/kg was not affected by treatment with the test substance. At necropsy, a whitish coloration of the stomach and intestines was noted in the animals given 1000 mg/kg. No apparent abnormalities were observed in the other animals.

The oral LD50 of the test substance THIOACETIC ACID is comprised between 200 and 350 mg/kg, in female rats.