Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1973
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: The study was conducted in mice comparable to the method described in OECD guideline 401.
Cross-referenceopen allclose all
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1973
Report Date:
1973

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Deviations:
not applicable
Principles of method if other than guideline:
Mice were starved overight before exposure. Test substance was prepared as a 20% emulsion in Tween-80 (10% aqueous dilution) and administered at a maximum dose volume of 20 mL/kg bw. Observation period was 14 days.
GLP compliance:
not specified
Test type:
acute toxic class method
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): EP1, O,O-diethyl-ditbiophosphoric acid

Test animals

Species:
mouse
Strain:
CD-1
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Weight at study initiation: 16 - 22 g
- Fasting period before study: overnight

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
other: Tween-80 (10% aqueous dilution)
Details on oral exposure:
VEHICLE
- Concentration in vehicle: 20% v/v in Tween-80
- Amount of vehicle (if gavage): maximum dose of 20 mL/kg

MAXIMUM DOSE VOLUME APPLIED: 20 mL/kg

Doses:
0, 0.64, 1.0, 1.6, 2.5, 4.0 mL/kg bw
No. of animals per sex per dose:
5/sex/dose
Control animals:
yes
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: weekly
- Necropsy of survivors performed: yes
- Other examinations performed: body weight
Statistics:
Not applicable.

Results and discussion

Preliminary study:
Results of a preliminary range finding tests indicated that the median lethal oral dose was in the region of 1 - 1.6 mL/kg bw.
Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
1.2 mL/kg bw
Based on:
test mat.
95% CL:
1.1 - 1.4
Mortality:
Death occured between 2 and 92 hours of treatment.
Clinical signs:
Lethargy was observed in treated animals within a few hours of dosing.
Body weight:
Not applicable
Gross pathology:
Darkening of the liver. Animals treated at 4 mL/kg showed ulceration of the stomach wall and intestine together with bleaching of parts of the liver.
Other findings:
Not applicable

Any other information on results incl. tables

No other information.

Applicant's summary and conclusion

Interpretation of results:
harmful
Remarks:
Migrated information Criteria used for interpretation of results: OECD GHS
Conclusions:
The acute median lethal oral dose (LD50) and its 95% confidence limits to mice of EP1 were calculated to be: 1.2 (1.1 - 1.4) mL/kg bw., corresponding to 0.24 (0.22 - 0.28) g/kg bw .
Executive summary:

An acute oral toxicity study was performed in mice on EP1.

EP1 was prepared as a 20% v/v emulsion in Tween-80 (10% aqueous solution) and administered at a maximum dosage volume of 20 mL/kg. Mice treated at Tween-80 (10%) in water (20 mL/kg) served as control.

During the 14 -days observation period, record was kept of all mortalities and signs of toxicity. All mice were examined macroscopically to identify target organs.

Autopsy revealed darkening of the liver and animals treated at 4 mL/kg (0.8 g/kg bw) showed ulceration of the stomach wall and intestine togeher with bleaching of parts of the liver.

The acute median lethal oral dose (LD50) of EP1 were calculated to be 1.2 mL/kg bw (0.24 g/kg bw).