Zeolite, cuboidal, crystalline, synthetic, non-fibrous

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:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1974

Report date:

1974

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Federal Hazardous Substances Labeling Act

Version / remarks:

CFR, Part 191, Chapter I. Title 21

Deviations:

not specified

GLP compliance:

not specified

Test type:

fixed concentration procedure

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Zeolite, cuboidal, crystalline, synthetic, non-fibrous

EC Number:

930-915-9

Cas Number:

1318-02-1

Molecular formula:

M2/nO • Al2O3 • ySiO2 • wH2O (n is the valency of the cation M, predominantly Na, y can range from 0.64 to 8.8, and w is the number of water molecules (general formula) Na: 1.34 - 24.02%, Al: 2.20 - 39.51%, Si: 15.52 - 68.64% (general composition); additionally, depending on the water quality: Ca, Mg and K might be present below 6%

IUPAC Name:

Zeolite, cuboidal, crystalline, synthetic, non-fibrous

Test material form:

solid: particulate/powder

Remarks:

no surface treatment

Specific details on test material used for the study:

Crystalline Aluminosilicate, very fine white powder, coded CH-216-110-1

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male

Details on test animals or test system and environmental conditions:

Twenty (20) Sprague-Dawley derived rats weighing between 200 and 225 grams were obtained from Charles River Breeding Laboratories. The animals were caged in groups of ten (10) and given Charles River Cubed Diet and tap water ad libitum. The animals were allowed at least five (5) days to accomodate to the laboratory conditions prior to being assigned to the study.

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

whole body

Vehicle:

clean air

Details on inhalation exposure:

The system operated as follows: The glass flask, auger assembly and dust ejector assembly were mounted on a vibrating platform. Vibration was produced by an electrical vibrator attached to the platform. Vibration from the platform maintained a flow of powder from the flask to the auger assemble. Rotational speed of the auger controlled the rate of compound feed to the dust ejector assembly. Dry, filtered, compressed air applied to the jet in the dust ejector created a negative pressure in the funnel which pulled the powder down into a high velocity air stream. This dust laden air was then led to the 56-liter all-glass exposure chamber. By observing the rate at which powder dropped into the funnel it was possible to insure that the system was operating correctly throughout the exposure periods.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

ca. 1 h

Remarks on duration:

s. "Details on study design" 2nd paragraph

Concentrations:

Mean actual concentrations of three measurements:
18.3 mg/l (group I)
2.4 mg/l (group II)

No. of animals per sex per dose:

10 (males only)

Control animals:

no

Details on study design:

Prior to the actual exposures, the generator's powder output was calibrated in terms of the.auger speed. This was accomplished by collecting, for a known time, the powder as it dropped from the tip of the auger and then weighing the collected powder. This was repeated a number of times at various auger speeds. From the resulting calibration curve (mg/min. vs rpm), the air pressure applied to the dust ejector was selected such that the resulting air flow would yield the nominal dust concentration in the exposure chamber.
Since the selected chamber air flow rate of 13 L/min used for Group II resulted in a significant equilibration time for a 56-liter chamber, the actual duration of exposure for Group II was extended to seventy-four (74) minutes so that the CT (concentration X time) would be equivalent to a sixty (60) minute exposure to a constant concentration.

In addition to calculating the nominal exposure concentrations, the actual exposure concentrations were determined during each exposure. This was accomplished by drawing a known volume of chamber air through pre-weighed glass fiber filters which were then reweighed. Three (3) such samples were taken during each one-hour exposure.

Results and discussion

Effect levels

Key result

Sex:

male

Dose descriptor:

LC0

Effect level:

>= 18.3 mg/L air (analytical)

Exp. duration:

60 min

Mortality:

no mortality

Body weight:

Body weights recorded prior to exposure and seven (7) and fourteen (14) days post-exposure did not reveal any effects related to the experimental compound.

Gross pathology:

All animals were necropsied following the fourteen (14) day observation period, and all organs were observed for gross abnormalities. There were no gross abnormalities which could be related to the exposure conditions.

Any other information on results incl. tables

There were no signs of toxicity in either exposure group during the exposure or the fourteen (14) day observation period.

Applicant's summary and conclusion

Conclusions:

There were no signs of toxicity in either exposure group during the exposure or the fourteen (14) day observation period. Therefore, the substance would be classified as non-toxic according to the definitions of Part 191, Chapter 1, Title 21 of the CFR, when administered via the inhalation route as an aerosol.

Executive summary:

The purpose of this study was to evaluate the acute inhalation toxicity of Crystalline Aluminosilicate according to requirements of the Federal Hazardous Substances Labeling Act, CFR, Part 191, Chapter I. Title 21. Two groups of ten (10) male rats were exposed for approximately one hour to actual mean concentrations of 2.4 and 18.3 mg/l. No signs of toxicity were observed.