3-(dimethylamino)-N,N-dimethylpropionamide

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1993

Report date:

1993

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: EPA (TSCA) Test Guidelines (Federal Register Vol. 50, No. 188) and 1987 OECD Guidelines for Testing of Chemicals (Section 4: Health Effects)

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

3-(dimethylamino)-N,N-dimethylpropionamide

EC Number:

241-304-5

EC Name:

3-(dimethylamino)-N,N-dimethylpropionamide

Cas Number:

17268-47-2

Molecular formula:

C7H16N2O

IUPAC Name:

3-(dimethylamino)-N,N-dimethylpropanamide

Test material form:

liquid

Test animals

Species:

mouse

Strain:

Swiss Webster

Sex:

male/female

Details on test animals or test system and environmental conditions:

Thirty-seven male and 37 female Swiss-Webster mice arrived on May 18, 1992, from Charles River Laboratories (Portage, MI). The male mice were designated by the supplier to be approximately 30 days old (the birth date was recorded as April 18, 1992) and 15 to 25 g upon arrival. Female mice were designated by the supplier to be approximately 27 days old (birth date recorded as April 21, 1992) and 10 to 20 g upon arrival. The females were nulliparous and nonpregnant.

Animals were housed in Room 155 upon arrival. On May 29, 1992, animals were moved into Room 164F [a Relocatable Containment Systema unit (Hazleton
Systems, Inc., Aberdeen, MD) in Room 1641 to termination of the study. All animals were assigned unique numbers and identified by cage cards. Animals
were also identified by an ear tagging procedure at 1 day following receipt.

The animals were separated by sex and group housed (up to 5/cage) in shoeboxtype plastic cages. ALPHA-drim bedding was placed in the cages and changed at 3 to 4-day intervals. An automatic timer was set to provide fluorescent lighting for a 12-hour photoperiod (approximately 0500 to 1700 hours for the light phase). Temperature and relative humidity were recorded continuously (Cole-Parmer Hygrothermograph@ Seven-Day Continuous Recorder, Model
No. 8368-00, Cole-Parmer Instrument Co., Chicago, IL). Temperature was routinely maintained at 65-77OF; relative humidity was routinely maintained at
40-708. Any minor exceptions to these specified ranges were noted in the raw data.

Tap water (Municipal Authority of Westmoreland County, Greensburg, PA) was available ad libitum except during dosing and was delivered by water bottles. Water analyses were provided by the supplier, the NUS Corporation, Materials Engineering and Testing Co., and Lancaster Laboratories, Inc. at regular intervals. EPA standards for maximum levels of contaminants were not exceeded. Pelleted, certified AGWAY@ PROLAB@ Animal Diet Rat, Mouse, Hamster 3000 (Agway Inc.) was available ad libitum except during dosing. Analyses for chemical composition and possible contaminants of each feed lot were performed by Agway Inc. and the results are included in BRRC files. Feed and water analyses reports were reviewed by the Study Director as they were available.

Administration / exposure

Route of administration:

other: intraperitoneal

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

Each dosing mixture was prepared prior to administration by diluting the appropriate amount of NIAX@ Catalyst DDPA with distilled water (prepared at
BRRC; CAS No. 7732-18-5). The resulting dilutions were mixed for approximately 15 min to 1.75 hours on a magnetic stirrer. The control substance (distilled water) was prepared at BRRC (standard methods). Doses were administered by intraperitoneal injection through a commercial 28 gauge (1/2-inch) needle attached to a disposable syringe. The exact amounts of test or control substance and mixture (where applicable) given to each mouse were recorded on the appropriate raw data form. Fresh dosing dilutions of the test substance were prepared for each day of administration.

Doses:

Males
500 mg/kg
354 mg/kg
250 mg/kg

Females
500 mg/kg
354 mg/kg
250 mg/kg

No. of animals per sex per dose:

5

Control animals:

yes

Details on study design:

Two mice (1 male and 1 female) were used for preliminary testing. Five male and 5 female mice were included on each of several dose levels in order to
obtain an LD50. An additional 5 male and 5 female mice were administered intraperitoneal doses of distilled water in order to serve as control animals
for the blood smear evaluations.

For individual animals, the dose volume was adjusted according to body weight (to give no more than 1.0 ml total volume). Dosed mice were observed
frequently for signs of toxicity on the first day of the test and twice a day thereafter (except on weekends or holidays when they were examined for death alone). Selected animals (4 males from 250 mg/kg and 3 females from 500 mg/kg) were subjected to blood smear collection approximately 48 hours after dosing. Blood smears were also obtained from all 10 control animals. Slides with the blood smears were fixed, stained, and subjected to polychromatophilic (PCE) to normochromatophilic (NCE) ratios (based on 1000 NCE). Mouse body weights were recorded on the day of dosing and at 7 and 14 days after dosing. After 14 days, all survivors were sacrificed by CO2 overdose. Necropsies were performed on all animals that were sacrificed or died (unless tissues were excessively autolyzed).

LDso's were calculated for both male and female mice, based on mortality data from the first 3 days and from the entire 14-day observation period. They
were calculated by the moving average method (Thompson, 1947). Slope estimates were made by the formula developed by Weil (1983).

Results and discussion

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LD50

Effect level:

354 mg/kg bw

Based on:

test mat.

Effect levels 2

Sex:

female

Dose descriptor:

LD50

Effect level:

374 mg/kg bw

Based on:

test mat.

Mortality:

Males
Dose group 500 mg/kg:
4/5

Dose group 354 mg/kg:
3/5

Dose group 250 mg/kg:
0/5.

Females
Dose group 500 mg/kg:
3/5

Dose group 354 mg/kg:
3/5

Dose group 250 mg/kg:
0/5

Clinical signs:

other: Males Dose group 500 mg/kg: Sluggishness, laboured and slow breathing at 20 min. Dose group 354 mg/kg: Sluggishness, laboured and slow breathing at 20 min, in two animals laboured breathing at 3 hours. Dose group 250 mg/kg: Sluggishness at 30 min. Recov

Gross pathology:

Males
Dose group 500 mg/kg:
1. Lungs mottled dark red; intestines brown.
2. Lungs mottled dark red; intestines brown.
3. Outer edges of liver dark maroon; intestines with red and dark red areas; lining of peritoneal cavity dark red.
4. Outer edges of liver dark maroon; intestines with red and dark red areas; lining of peritoneal cavity dark red.
5. No gross lesions.

Dose group 354 mg/kg:
1. Outer edges of liver black; intestines brown.
2. Lungs mottled dark rod; outer edge of liver black; stomach (glandular portion), intestines brown; lining of peritoneal cavity brown.
3. Lungs mottled dark red; liver black; intestines brown; lining of peritoneal cavity brown to black.
4. Necropsy not performed (tissues excessively autolysed).
5. Necropsy not performed (tissues excessively autolysed).

Dose group 250 mg/kg:
1. – 5. No gross lesions

Females
Dose group 500 mg/kg:
1. Liver and intestines with brown to black areas (tissues autolysed).
2. Lungs dark red; liver brown with black (necrotic) areas; stomach, intestines brown.
3. Lungs light rod; outer edges of liver dark maroon; intestines dark red; lining of peritoneal cavity dark red.
4. Lungs light red; outer edges of liver dark maroon; intestines dark red (hemorrhaged) with brown (necrotic) areas.
5. No gross lesions

Dose group 354 mg/kg:
1. Lungs mottled dark red; outer edges of liver black; intestines with brown and dark brown areas; lining of peritoneal cavity brown.
2. Lungs red; outer edges of liver black; stomach dark brown; intestines dark brown to black lining of peritoneal cavity brown.
3. Lungs mottled dark red; stomach brown (glandular portion); intestines dark brown.
4. No gross lesions.
5. Lungs mottled dark red; liver mottled dark brown and dark maroon; stomach dark brown and black; intestines with dark brown to black areas.

Dose group 250 mg/kg:
1.– 5. No gross lesions.

Any other information on results incl. tables

In preliminary testing, 1 male mouse and 1 female mouse were dosed with 1000 mg/kg of test substance; both animals died. For the definitive test, the intraperitoneal LD50's for the test substance, expressed in terms of test substance as received, were 297 mg/kg b.w. for male mice and 324 mg/kg for female mice. Signs of toxicity observed included sluggishness, laboured and slow breathing, a marked unsteady gait (in 1) and prostration (in 1). Deaths occurred within 1 to 6 days. Most survivors recovered within 3 to 4 hours. Three female mice (dosed with 354 mg/kg) exhibited an apparent recovery within 3 hours, but then died at 3 to 4 days. Necropsy of mice that died revealed light to dark red lungs (some mottled), brown to black livers (necrotic in l), a mottled dark maroon to dark brown liver (in l), outer edges of livers dark maroon to black, brown to black stomachs, discoloured intestines (red, brown or black) and the intestines of 1 dark red (haemorrhaged) with brown (necrotic) areas. The lining of the peritoneal cavities were also dark red to brown (or black) in several animals. The tissues of 2 male mice (at dose 354 mg/kg) were excessively autolyzed and, therefore, no necropsy was performed on either animal. There were no gross lesions evident in survivors at necropsy.

 

Five of 5 male and 5 of 5 female mice survived after receiving intraperitoneal doses of 10.0 g/kg of the control substance (distilled water). There were no signs of toxicity apparent during the 14-day observation period and no gross lesions were evident at necropsy.

 

The blood smear evaluations were conducted on male mice receiving 250 mg/kg and female mice receiving 500 mg/kg of test substance - doses which produced significant signs of toxicity. The mean PCE/1000 NCE was 31.0 for males and 27.3 for females. The ratios for control mice (dosed with 10.0 g/kg of water) were 24.6 and 28.4 for males and females, respectively.

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

The test substance is moderately toxic to mice following intraperitoneal injection. There were no adverse effects noted in any animal receiving intraperitoneal control doses with distilled water. There was no evidence that the test substance either suppressed or stimulated proliferation of polychromatophilic erythrocytes.