Registration Dossier

Diss Factsheets

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study described in sufficient detail.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1989
Report date:
1989

Materials and methods

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

Test material

Constituent 1
Reference substance name:
Potassium tert-butanolate
EC Number:
212-740-3
EC Name:
Potassium tert-butanolate
Cas Number:
865-47-4
IUPAC Name:
potassium 2-methylpropan-2-olate

Test animals

Species:
rat
Strain:
other: Bor:WISW(SPF Cpb)
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: F. Winkelmann, 4799 Borchen
- Weight at study initiation: 205 g male, 160 g female
- Fasting period before study: 16 h
- Housing: Makrolon Typ III
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 5-8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20°C +/-1°C
- Humidity (%):60% +/-5%
- Air changes (per hr):15 oer hr
- Photoperiod (hrs dark / hrs light): 12 hrs dark /12 hrs light

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
water
Details on oral exposure:
VEHICLE
- Concentration in vehicle: 5.1-7.94 %
- Amount of vehicle (if gavage): volume 10 cm3/kg
Doses:
510 mg/kg bw
631 mg/kg bw
794 mg/kg bw
No. of animals per sex per dose:
5 animals per sex per dose
Control animals:
no
Statistics:
For body weights mean values were calculated. LD50 were calculated according to Litchfield and Wilcoxon with 95% confidence intervals.

Results and discussion

Effect levelsopen allclose all
Sex:
male/female
Dose descriptor:
LD50
Effect level:
690 mg/kg bw
Based on:
test mat.
95% CL:
620 - 768
Sex:
male
Dose descriptor:
LD50
Effect level:
715 mg/kg bw
Based on:
test mat.
95% CL:
611 - 837
Sex:
female
Dose descriptor:
LD50
Effect level:
675 mg/kg bw
Based on:
test mat.
95% CL:
587 - 776
Mortality:
794 mg/kg: 7/10 animals died
631 mg/kg: 4/10 animals died
510 mg/kg: 0/10 animals died
Clinical signs:
Animals showed a hunked posture, closed eyes, gasping, oral and nasal bloody discharge, increased repsiratory rate, diarrhea and cachexia, lateral and prone position, sedation and ataxia.
Body weight:
Animals had a reduced body weight compared to the beginning of the study.
Gross pathology:
Dissection showed necrosis in mucosa of gastro-esophagaeal vestibule and in the stomach. Peritoneum had a blue-red colour, abdominal viscus sticked together and a hyperemia of the renal pelvis and of the intestinal mucosa were found. Atrophy was found in the stomach, spleen and mesentary. A thickening of the mucosa of gastro-esophagaeal vestibule and in the stomach was detected.

Applicant's summary and conclusion

Conclusions:
The pathological findings were based on the corrosive properties of the test substance and do not support a classification.