Estr-5(10)-en-17-one, 3,3-dimethoxy-

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Feb 2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Version / remarks:

17 December 2001

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

3,3-Dimethoxyestr-5(10)-en-17-one

EC Number:

606-278-5

Cas Number:

19257-34-2

Molecular formula:

C20 H30 O3

IUPAC Name:

3,3-Dimethoxyestr-5(10)-en-17-one

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Tierzucht Schönwalde GmbH, Germany
- Weight at study initiation: males : 110-118 g; females : 101-107 g
- Fasting period before study: 18 - 18.5 hours
- Housing: individually, cage conditions: conventional
- Diet (e.g. ad libitum): pell. Altromin ®R ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21-22
- Humidity (%): 42-56
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: 0.9 % NaCl + 0.085 % Myrj 53 in bidist. water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 mg/mL
- Amount of vehicle (if gavage): 10mL/kg

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg

CLASS METHOD
- Rationale for the selection of the starting dose: Limit test

Doses:

2000 mg/kg

No. of animals per sex per dose:

3

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Clinical observations: All animals were checked three times on administration day and once daily on the following days; body weight: Body weight was determined at the start (day 1), on day 7 and at the end (day 14) of the study.
- Necropsy of survivors performed: yes
- Clinical signs including body weight: All alterations of the baseline condition of the animals were recorded.

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

Not observed

Clinical signs:

other: Only observed in one animal one hour after dosing , all other animals showed no clinical signs.

Gross pathology:

No findings

Any other information on results incl. tables

No animal died in the course of the study. After single oral application of 2000 mg/kg one male animal showed slight apathy and reddened rhinorrhea only one hour after administration. All other animals were without clinical findings over the whole observation period. The body weight gain on days 7 and 14 was within the normal range for rats of this age and strain, which are routinely used in the laboratory. Autopsy revealed no compound-related findings.

Applicant's summary and conclusion

Conclusions:

A single oral administration of the test substance by gavage to male and female rats at the limit-dose 2000 mg/kg was tolerated without mortalities, effects on body weight gain and gross pathological findings. At 2000 mg/kg slight apathy and reddened rhinorrhea were observed in one male animal only one hour after administration. According to OECD TG 423 the oral LD50 of the test item is therefore > 2000 mg/kg body weight

Executive summary:

In an acute oral toxicity study according to OECD TG 423 (adopted 17 December 2001), groups of fasted, Wistar rats, female and male weighing, (3/sex) were given a single oral dose of Dimethoxyketal in 0.9 % NaCl + 0.085 % Myrj 53 in bidist. water at a dose of 2000 mg/kg bw and observed for 14 days.

Oral LD50 Combined > 2000 mg/kg bw

Limit test
No mortality occurred during the test
After single oral application of 2000 mg/kg one male animal showed slight apathy and reddened rhinorrhea only one hour after administration. All other animals were without clinical findings over the whole observation period. There were no necropsy findings or changes in body weight.

The test item is of low Toxicity based on the LD50 in male and female Wistar rats.