Flue dust, zinc-refining

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

not applicable

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well documented and scientifically good . Tests done according to standard protocol. Good quality and considered useful for setting the reference value for acute inhalation toxicity

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Flue dust, zinc-refining

EC Number:

273-760-6

EC Name:

Flue dust, zinc-refining

Cas Number:

69012-63-1

Molecular formula:

Not applicable - UVCB

IUPAC Name:

Zinc oxide enriched flue dust

Details on test material:

name of test substance: probe B (= Wälzoxid)
description: grey dust
batch number: feb '99
purity: unknown
aggregate state at room temp: solid
density (g/cm3 at 20°C): +/-5
solubility of the test item: considered to be stable under the conditions specified below
expiry date: dec 2000
storage conditions: in original , tightly sealed container, at room temp (20-25°C) protected from direct sunlight

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: RCC Ltd Biotechnology and Animal Breeding Division CH-4414 Füllinsdorf/Switserland
- Age at study initiation: 10 weeks for males and females
- Weight at study initiation (g): males: 211.1-228.6; females: 196.3-209.2
- Housing: in groups of 5 in Makrolon type-4 cages
- Diet: pelleted standard Kliba 3433, batch no 38/98, rat maintenance diet (Kliba Mühlen AG, CH-4303 Kaiseraugst ad libitum
- Water: community tap water from Füllinsdorf ad libitum
- Acclimation period: 1 week


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-21
- Humidity (%): 50-82
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

inhalation

Type of inhalation exposure:

nose only

Vehicle:

other: unchanged (no vehicle)

Details on inhalation exposure:

Inhalation exposure system:
The animals were confined separately in restraint tubes which were positioned radially around the flow-past, nose-only exposure chambers
The design of this chamber is based upon the fluid dynamic modelling of the test atmosphere flow. It ensures a uniform test item distribution, provides a constant stream of 'fresh' test item to each animal, and precluses re-breathing the exhaled air.

Test atmosphere generation:
The test item was generated using a rotating brush aerosol generator (CR3020, CR equipements, SA, CH-1295 Tannay, Switserland)connected to a micronising jet mill.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

ca. 4 h

Concentrations:

5.371 mg/l air

No. of animals per sex per dose:

10

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
mortality/viability: once daily during the acclimatisation phase, once before exposure on the day of exposure (test day1), once per hour during exposure, once after exposure on test day 1, and twice daily during the remainder of the observation period
body weights: recorded on test datys 1 (before exposure), 4, 8 and 15 (day of necroscopy) using a Mettler PM 4000 balance
clinical signs: once per hour during exposure (only grosly abnormal signs, as the animals were in restraint tubes), once after exposure on test day 1, and once daily thereafter

Statistics:

the LOGIT-Model was not used as only one group was exposed and there were no deaths

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 5.371 mg/L air

Exp. duration:

4 h

Mortality:

No spontaneous deaths occured

Clinical signs:

other: No clinical signs during the 15 day observation period

Body weight:

A slight, transient loss in mean body weights was evident in male and female animals from test days 1 to 4

Gross pathology:

Necroscopy of each animal did not reveal any macroscopical findings

Other findings:

none

Any other information on results incl. tables

A relationship of the slight, transient losses in mean body weight with the treatment with test item could not be fully rulled out, although the generated data did not permit any conclusion to what extent this finding was attributable to slight physical stress which may have occured during restraint in the exposure tubes and to what extent to the treatment with test item.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Tests done according to standard protocol. Good quality and considered useful for setting the reference value for acute inhalation toxicity

Executive summary:

The purpose of this study was to assess the acute inhalation toxicity of PROBE B Wälzoxid B.U.S. Zinkrecycling Freiberg GMBH when administered to rats for a single continuous 4 -hour period, followed by an observation period of 14 days.

This acute 4 -hour inhalation toxicity test according to OECD 403 with 5.371 mg/l air inhalation of Waelz zinc oxide demonstrated that the LC50 for rats was >5.371 mg/l air