N,N'-hexane-1,6-diylbis[3-(3,5-di-tert-butyl-4-hydroxyphenylpropionamide]

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Study period:

1973

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: This study was performed by a CRO known for falsifying data and the quality of this study cannot be judged. Since acute toxicity data by inhalation is not required according to Annex VIII of regulation (EC) 1907/2006, this IBT study is disregarded.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1973

Report date:

1973

Materials and methods

Principles of method if other than guideline:

The test material powder was passed through a high-velocity stream of clean dry air (-40°C dewpoint). The resulting air and dust mixture was then introduced into fhe exposure chamber at the top center, dispersed by a baffle plate, and exhausted at the bottom of the chamber. Animals were exposed for four hours in in a specially constructed Plexiglas inhalation chamber having a capacity of 70 liters. The chamber was designed so that the animals could be introduced to the test atmosphere after the maximum dust concentration was established. Each animal was caged separately during exposure to minimize filtration of inspired air by animal fur.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

N,N'-hexane-1,6-diylbis[3-(3,5-di-tert-butyl-4-hydroxyphenylpropionamide]

EC Number:

245-442-7

EC Name:

N,N'-hexane-1,6-diylbis[3-(3,5-di-tert-butyl-4-hydroxyphenylpropionamide]

Cas Number:

23128-74-7

Molecular formula:

C40H64N2O4

IUPAC Name:

N,N'-hexane-1,6-diylbis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanamide]

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: ARS/Sprague-Dawley Breeding Laboratories, Madison, Wisconsin
- Weight at study initiation: 277 grams
- Housing: individually in stock cages
- Diet: Purina Rat Chow, Ralston Purina Company, ad libitum
- Water: ad libitum except during inhalation exposure
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
not specified

Administration / exposure

Route of administration:

inhalation: dust

Type of inhalation exposure:

whole body

Details on inhalation exposure:

GENERATION OF ATMOSPHERE
The test material powder was passed through a high-velocity stream of clean dry air (-40°C dewpoint). The resulting air and dust mixture was then introduced into fhe exposure chamber at the top center, dispersed by a baffle plate, and exhausted at the bottom of the chamber. Air flow rate through the system (6.5 L/min at 29. 92 inches Hg and 25°C) was measured with a rotameter connected upstream of the dust feeder. The rotameter was calibrated -with a wet-test meter after the exposure was completed. The temperature of the test atmosphere was 27 °C and the pressure was 29.94 inches Hg.

EXPOSURE
Test animals were exposed in a specially constructed Plexiglas inhalation chamber having a capacity of 70 liters. The chamber was designed so that the animals could be introduced to the test atmosphere after the maximum dust concentration was established. Each animal was caged separately during exposure to minimize filtration of inspired air by animal fur.

DETERMINATION OF CONCENTRATION
The concentration of test material dust present in the exposure chamber was determined by sampling the test atmosphere in the breathing zone of the animals being exposed. The total weight of dust collected on a glass fiber filter was divided by the total volume of air drawn through the filter during the sampling period. Air flow rate for sampling was regulated by a calibrated limiting orifice. The average analytical concentration of airborne dust was obtained by repeated air sampling.

Analytical verification of test atmosphere concentrations:

no

Duration of exposure:

4 h

No. of animals per sex per dose:

5

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of weighing: before exposure and at the end of observation period.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 3.9 mg/m³ air

Based on:

test mat.

Remarks on result:

other: Maximum attainable concentration at conditions stated.

Mortality:

No mortality occurred.

Clinical signs:

other: No untoward behavioral reactions were observed during the four-hour inhalation period or the 14-day observation period.

Body weight:

The average 2-week body weight gains were within the normal limits.

Gross pathology:

Necropsy revealed slight focal discoloration of the lungs in two rats and minimal to slight petite discoloration of the lungs in six rats. This gross pathologic change is not uncommon in laboratory rats , and cannot definitely be attributed to inhalation of test material. All other tissues and organs examined did not reveal any gross pathologic alterations.