N,N-dimethylacrylamide

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented report which meets basic scientific principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Report date:

1998

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: US OSHA Regulation: 29 CFR 1910.1200

GLP compliance:

not specified

Test type:

other: Inhalation Hazard Test

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

N,N-dimethylacrylamide

EC Number:

220-237-5

EC Name:

N,N-dimethylacrylamide

Cas Number:

2680-03-7

Molecular formula:

C5H9NO

IUPAC Name:

N,N-dimethylacrylamide

Details on test material:

- Name of test material (as cited in study report): N,N-dimethylacrylamide
- Batch number: 7H147
- Physical state: clear colorless liquid
- Storage condition of test material: room temperature

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Sprague Dawley, Inc., Indianapolis, IN
- Age at study initiation: 4 weeks
- Weight at study initiation: 230-258 g (males), 175-213 g (females)
- Housing: one per suspended, wire bottom, stainless steel cage
- Diet: PMI Lab Diet Formula #5008, ad libitum except during the exposure period
- Water: Municipal water supply from automatic water systemn, ad libitum except during the exposure period
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22±3
- Humidity (%): 30-80
- Air changes (per hr): 10-12
- Photoperiod (hrs dark / hrs light): 12 / 12

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

nose only

Vehicle:

air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure chamber volume: 15.5 L
- Air flow: 5.66 L/min
- Method of holding animals in test chamber: polycarbonate tubes inserted in the body of the chamber
- Method of conditioning air: calibrated orifice plate at a rate of 21.9 air changes per hour
- Vapour generation: The vapor was generated by bubbling air through fritted tubes into 4 Erlenmeyer flasks, each containing 300 mL of the test substance. The air was heated prior to enrering tlasks by heating tape wrapped around the air tubes to approximately 35 °C. The vapor was pulled from the flasks through the exposure chamber.

TEST ATMOSPHERE
- Brief description of analytical method used: gas chromatography
- Samples taken from breathing zone: yes

Analytical verification of test atmosphere concentrations:

yes

Remarks:

gas chromatography

Duration of exposure:

1 h

Concentrations:

776 ppm (highest achievable vapour concentration at 35 ºC)

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: observations were made frequently on day of exposure and at least once daily thereafter, body weights were recorded just prior to inhalation exposure and on days 7 and 14.
- Necropsy of survivors performed: yes

Statistics:

In order to calculate a mean exposure, the Mean Value Theorem of Calculus was used to properly weigh the concentration, since the concentrations could not be measured continuously. This method weighs concentrations based on the time span of each concentration. A concentration can be calculated for each minute, which btter represents the exposure concentration received by each animal.

Results and discussion

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 776 ppm

Based on:

test mat.

Exp. duration:

1 h

Remarks on result:

other: original value, highest achievable vapour concentration at 35 ºC

Effect levels 2

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 3.16 mg/L air

Based on:

test mat.

Exp. duration:

1 h

Mortality:

There was no mortaIity during the study.

Clinical signs:

other: Fur coated with feces/urine was observed in all animals at 1 hour after exposure. For the remainder of the study, all animals appeared normal.

Body weight:

Body weight gain of surviving animals was unaffected by the administration of the test substance.

Gross pathology:

The gross necropsy conducted on each animal at termination of the study revealed no observable abnormalities, except for red lungs in three females.