Registration Dossier

Diss Factsheets

Toxicological information

Acute Toxicity: oral

Currently viewing:

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1979
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study conducted before GLP and guidelines but giving enough valuable details to draw a conclusion on substance toxicity by oral route and classification.
Cross-referenceopen allclose all
Reason / purpose for cross-reference:
reference to same study
Reason / purpose for cross-reference:
reference to other study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1979
Report date:
1979

Materials and methods

Test guideline
Qualifier:
no guideline available
Principles of method if other than guideline:
Groups of Sprague Dawley rats (5/sex/dose) were given a single oral dose of undiluted test substance at 2000, 3000, 3500, 4000 and 5000 mg/kg bw. Animals were then observed for mortality, clinical signs and bodyweights for 14 days and were all macroscopically necropsied after death or sacrifice.
GLP compliance:
not specified
Test type:
standard acute method
Limit test:
no

Test material

Constituent 1
Chemical structure
Reference substance name:
2-hydroxy-4-(methylthio)butyric acid
EC Number:
209-523-0
EC Name:
2-hydroxy-4-(methylthio)butyric acid
Cas Number:
583-91-5
Molecular formula:
C5H10O3S
IUPAC Name:
2-hydroxy-4-(methylthio)butanoic acid
Details on test material:
- Name of test material (as cited in study report): LMA-88%

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS

- Weight at study initiation: see table 1

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
unchanged (no vehicle)
Details on oral exposure:
No data
Doses:
2000, 3000, 3500, 4000 and 5000 mg/kg bw
No. of animals per sex per dose:
5
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: observations: daily; weighing: at days 0, 7 and 14 after dosing
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs and body weight
Statistics:
None

Results and discussion

Preliminary study:
No data
Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
3 170 mg/kg bw
Based on:
test mat.
95% CL:
>= 2 260 - <= 4 000
Mortality:
See table 1. Combined: 2/10 at 2000 mg/kg bw, 4/10 at 3000 mg/kg bw, 5/10 at 3500 mg/kg bw, 9/10 at 4000 mg/kg bw and 7/10 at 5000 mg/kg bw
Clinical signs:
Hypoactivity, ataxia, ptosis, salivation and lacrimation were observed in some animals after intubation. Chromodacryorrhea was seen in one animal at the highest dose.
Body weight:
See table 1
Gross pathology:
Hemorrhages were observed in the lungs and gastrointestinal tracts of some decedents. Viscera appeared unremarkable in all survivors at terminal sacrifice.
Other findings:
No data

Any other information on results incl. tables

Table 1: summary results

Dosage

(mg/kg bw)

Body weight (g)

Mortalities

Time of mortality (day:number of deaths)

Day 0

Male/female

Day 7

Male/female

Day 14

Male/female

Male

Female

Combined

2000

206/146

278/189

324/206

0/5

0/5

2/10

Day 2:1, day 4:1

3000

201/146

258/195

304/212

2/5

2/5

4/10

Day 1:3, day 2:1

3500

207/150

275/204

316/228

2/5

3/5

5/10

Day 1:5

4000

208/146

- /174

- /205

5/5

4/5

9/10

Day 1:5, day 2:2, day 6:2

5000

206/152

253/ -

319/ -

2/5

5/5

7/10

Day 1:6, day 2:1

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
The oral LD50 for LMA-88% is 3170 mg/kg in rats. As it is higher than 2000 mg/kg bw, it is not classified according to the Annex VI to the Directive 67/548/EEC and the CLP Regulation (EC) N° (1272-2008).
Executive summary:

In an acute oral toxicity study, groups of Sprague Dawley rats (5/sex/dose) were given a single oral dose of LMA-88% undiluted at 2000, 3000, 3500, 4000 and 5000 mg/kg bw. Animals were then observed for mortality, clinical signs and bodyweights for 14 days and were all macroscopically necropsied after death or sacrifice. Mortality occurred at all doses. Signs of toxicity observed were hypoactivity, ataxia, ptosis, salivation and lacrimation in some animals after intubation. Chromodacryorrhea was seen in one animal at the highest dose. Abnormalities noted at necropsy of animals that died during the study were hemorrhages in the lungs and gastrointestinal tracts. Viscera appeared unremarkable in all survivors at terminal sacrifice.

The combined oral LD50 was 3170 mg/kg with 95% confidence limits between 2260 and 4000 mg/kg bw.

The oral LD50 for LMA-88% is higher than 2000 mg/kg bw in rats therefore it is not classified according to the Annex VI to the Directive 67/548/EEC and the CLP Regulation (EC) N° (1272-2008).