Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1985-05-22 to 1985-06-26
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: All scientific necessary information for evaluation is available. Only the translation of the study report is available. The study was performed according to OECD guideline 401.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1985
Report Date:
1985

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Version / remarks:
Not mentioned in report
Deviations:
not specified
GLP compliance:
not specified
Test type:
standard acute method
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
- Name of test material (as cited in study report): Praeparat EK, Acetic acid (2-benzothiazolylthione)
- Physical state: solid, powder
- Analytical purity: 100%
- Impurities (identity and concentrations): n.a.
- Lot/batch No.: n.a.

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
other: 0.5% Methylcellulose 400 cps
Doses:
First trial: 1500, 2000 and 2500 mg/kg bw and
Due to mortalities seen with the first three dose levels, additional three dose levels were tested : 1000, 3000, 500 mg/kg bw
No. of animals per sex per dose:
5
Control animals:
no
Details on study design:
The test started with three dose levels: 1500, 2000 and 2500 mg/kg bw
Due to mortalities seen with the first three dose levels, additional three dose levels were tested : 1000, 3000, 500 mg/kg bw. Gross pathology was investigated at all animals that died during the observation period as well as at all surviving animals at termination of observation period.
Statistics:
according to method published by J. Litchfield and F. Wicoxon (J. Parmacology, 1949, 95-99)

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
1 580 mg/kg bw
Based on:
test mat.
95% CL:
> 1 405 - < 1 776

Applicant's summary and conclusion

Interpretation of results:
Toxicity Category IV
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
Based on the results of above mentioned study the median lethal dose (LD50) of the test substance after single oral administration to male and female rats, observed over a period of 14 days is 1580 mg/kg bw.
Executive summary:

A study was performed to determine the acute oral median lethal dose (LD50) of the test material, administered per oral gavage as a solution in 0.5% methyl cellulose 400 cps in the Sprague-Dawley strain rat. The method used followed that described in the OECD Guidelines for Testing of Chemicals (1981) No. 401 "Acute Oral Toxicity" referenced as EU Method B.1 (Acute Toxicity (Oral)).

Ten fasted animals per dose group (five per sex) were given a single oral dose of test material at dose levels of 1500, 2000 and 2500 mg/kg bw. Mortality occurred between 2 hours and 6 days after treatment. Due to mortalities seen in each dose group additional three dose levels ( i.e. 500, 1000, 3000 mg/kg bw) were tested in rat groups of 5 females and 5 males per dose thereafter. At 3000 mg/kg bw dose level 5 females and 5 males died within 2 days after treatment. At 1000 mg/kg bw dose 2 females and one male died within 7 days. At the 500 mg/kg bw dose group no mortality occurred. Clinical signs observed at all treated animals during the first 24 hours after treatment were hypoactivity. Some of the rats that died between day 5 and 7 after application appeared cachectic. Necropsy of the animals that died during the study period revealed hyperemia and/or erosion and/or haemorrhagic ulceration of the mucosa of the stomach. No abnormalities were noted at all surviving animals that were killed at end of study period.

Based on the results of above mentioned study, the median lethal dose (LD50) of the test substance after single oral administration to male and female rats, observed over a period of 14 days is 1580 mg/kg bw.