N-nitro-N-(3-methyl-3,6-dihydro-2H-1,3,5-oxadiazin-4-yl)amine

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

August - October 1995

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

This study follows OECD 401 acute toxicity which is now deleted (in 2002). But the authors state that the original OECD protocol is followed and it is carried out to GLP standards. Only two doses were tested so no dose-response relationship is reported. The LD50 lies between 1000 and 2000 mg/l. Use of control organisms is unreported.

Cross-reference

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

use of control animals is unreported; only two doses

GLP compliance:

yes

Remarks:

This study was performed in compliance with Good Laboratory Practice (GLP) in Switzerland, Procedures and Principles, March 1986, issued by the Federal Department of the Interior and the Intercantonal Office for the Control of Medicaments, Switzerland.

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

431-060-1

EC Name:

-

Cas Number:

153719-38-1

Molecular formula:

C4H8N4O3

IUPAC Name:

3-methyl-N-nitro-3,6-dihydro-2H-1,3,5-oxadiazin-4-amine

Details on test material:

- Name of test material (as cited in study report): CA 2343 A (intermediate of CGA 293343)
- Physical state: fine, white powder
- Analytical purity: 96.7 %
- Batch No.: P. 503005
- Storage condition of test material: 0 - 5 °C
- Date of reanalysis: December 1996
- Test material received: August 16, 1995

Test animals

Species:

rat

Strain:

other: Tif: RAI f (SPF)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Ciba-Geigy Limited, Animal Production, Stein, Switzerland
- Age at study initiation: young adults
- Weight at study initiation: 174 - 217 g
- Fasting period before study: overnight
- Housing: Macrolon cages type 4, with standardized soft wood bediing (Societe Parisienne des Sciures, Pantin, Paris); animals were segregated by sex and group-housed (5 animals per cage)
- Animal identification: color code on the tail (dash-dot code, painted with a felt-tipped waterproof marker)
- Diet: ad libitum (NAFAG 890, NAFAG, Gossau/SG, Switzerland)
- Water: ad libitum
- Acclimation period: at least 5 days before administration


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 2 °C
- Humidity (%): 55 +/- 10 %
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12 / 12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: 0.5 % (w/v) carboxymethylcellulose in 0.1 % (w/v) aqueous polysorbate 80

Details on oral exposure:

VEHICLE
- Volume applied: 10 ml/kg body weight
- concentration of test substance in vehicle: 100mg/ml and 200mg/ml

Dose Levels, sex group:
- 1000 mg/kg body weight, males and females
- 2000 mg/kg body weight, males and females


- Rationale for dose selection: the dose level was selected according to OECD 401 and pretest results

Doses:

1000 and 2000 mg/kf body weight

No. of animals per sex per dose:

5 animals per sex per dose;
total number of animals: 20 (10 males/10 females)

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations (signs and symptoms): daily for 14 days
- Frequency of observations (mortality): daily; a.m. and p.m. on working days, a.m. on weekends
- Frequency of weighing: immediately before administration and on days 7 and 14
- Necropsy of survivors performed: yes

Statistics:

Mean and standard deviations of body weight changes

Results and discussion

Effect levels

Effect levels 1

Sex:

female

Dose descriptor:

LD50

Effect level:

> 1 000 - < 2 000 mg/kg bw

Effect levels 2

Sex:

male

Dose descriptor:

LD50

Effect level:

> 1 000 - < 2 000 mg/kg bw

Effect levels 3

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 1 000 - < 2 000 mg/kg bw

Mortality:

- 2000 mg/kg: 3 of 5 males and all females were found dead within 7 hours after administration of the test article
- 1000 mg/kg: all animals survived to the scheduled sacrifice

Clinical signs:

other: IN-LIFE OBSERVATIONS: - 2000 mg/kg, males and females: dyspnea, reduced locomotor activity, convulsions, hunched posture and piloerection - 2000 mg/kg, individual males: tremor, ataxia, diarrhea and vental recumbency; surviving males recovered within 3 da

Gross pathology:

- spontaneously dying animals were submitted to a gross necropsy as soon as possible
- at necropsy, no deviations from normal morphology were found in all animals

Other findings:

None

Any other information on results incl. tables

Body weight and necropsy findings:

 

1000 mg/kg, males

Animal Number	Body weights (g) Day 0        7         14			*	Gross Necropsy Findings
1 2 3 4 5   mean SD	195 198 194 195 211   199 7.1	231 247 228 231 248   237 9.7	295 293 289 279 302   292 8.5	TS TS TS TS TS	no observable abnormalities no observable abnormalities no observable abnormalities no observable abnormalities no observable abnormalities

 

1000 mg/kg, females

Animal Number	Body weights (g) Day 0        7         14			*	Gross Necropsy Findings
1 2 3 4 5   mean SD	184 191 174 180 190   184 7.1	202 196 199 192 204   199 4.8	215 204 218 216 215   214 5.5	TS TS TS TS TS	no observable abnormalities no observable abnormalities no observable abnormalities no observable abnormalities no observable abnormalities

* TS   terminal sacrifice

 

2000 mg/kg, males

Animal Number	Body weights (g) Day 0        7         14			*	Gross Necropsy Findings
1 2 3 4 5   mean SD	196 210 208 205 217   207 7.7	239 236       238 2.1	284 284       284 0.0	7h TS TS 2h 24h	no observable abnormalities no observable abnormalities no observable abnormalities no observable abnormalities no observable abnormalities

 

2000 mg/kg, females

Animal Number	Body weights (g) Day 0        7         14			*	Gross Necropsy Findings
1 2 3 4 5   mean SD	187 202 197 194 189   194 6.1			4h 5h 5h 5h 24h	no observable abnormalities no observable abnormalities no observable abnormalities no observable abnormalities no observable abnormalities

* TS   terminal sacrifice

* <>   found dead < > hours after administration

 

Applicant's summary and conclusion

Interpretation of results:

Toxicity Category IV

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

At 2000 mg/kg CA 2343 A (intermediate of CGA 293343) elicited evident signs of acute toxicity and mortality in male and female rats. Signs of acute toxicity, but no mortality, were seen after treatment with 1000 mg/kg. CA 2343 A is classified as Acute Tox. 4.

Executive summary:

In an acute oral toxicity study (OECD 401), groups of 10 fasted young adult albino rats (Tif: RAI f (SPF)) of both sexes (5 animals per group) were given (gastric intubation) a single oral dose of CA 2343 A (intermediate of CGS 293343) in 0.5 % (w/v) carboxymethylcellulose (in 0.1 % (w/v) aqueous polysorbate 80) in concentrations of 1000 mg/kg bw and2000 mg/kg bw. The animals were observed for a period of 14 days after administration of the test substance. The following LD50 was determined for CA 2343 A:

 Oral LD₅₀    Males > 1000 and < 2000  mg/kg bw

                      Females > 1000 and < 2000  mg/kg bw

                      Sexes combined > 1000 and < 2000  mg/kg bw

 

At 2000 mg/kg, 3 of 5 males and all females were found dead within 7 hours after administration. At 1000 mg/kg all animals survived to the scheduled sacrifice.

In-life observations indicating treatment related systemic effects such as dyspnea, reduced locomotor activity, convulsions, hunched posture and piloerection were recorded in both sexes at 2000 mg/kg. Tremor, ataxia, diarrhea and vental recumbency were limited to individual males. Surviving animals recovered within 3 days. At 1000 mg/kg, in-life observations such as reduced locomotor activity, hunched posture and piloerection were recorded in both sexes. All animals recovered within 6 days.

Body weights of surviving animals were unaffected by the treatment.

At necropsy, no deviations from normal morphology were found in all animals.

The LD50 was determined by linear interpolation to be 1500 mg/kg bw for females and 1830 mg/kg bw for males. Therefore, CA 2343 A is classified as Acute Tox. 4.