Aluminium sulphate

Repeated dose toxicity: inhalation

Administrative data

Endpoint:

chronic toxicity: inhalation

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Reliable without restrictions. Well-presented study, with relevant measurement of chemical concentrations

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1973

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 452 (Chronic Toxicity Studies)

GLP compliance:

not specified

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Aluminium

EC Number:

231-072-3

EC Name:

Aluminium

Cas Number:

7429-90-5

IUPAC Name:

aluminum

Test material form:

aerosol dispenser: not specified

Remarks:

migrated information: aerosol

Details on test material:

- Name of test material-other- very fine metallic aluminium powder , Aluminium

- Name of test material : Aluminium
- CAS №: 7429-90-5
- EC №: 231-072-3
- Molecular formula : Al
- Molecular weight (if other than submission substance): 26,98 g•mol−1
- Structural formula attached as image file (if other than submission substance): see Fig.1
- Substance type: metal
- Physical state: solid
- Density : 2.70 g•cm−3
- Melting point: 660.32 ° ,C,
- Boiling point: 2519 ° C,
-Solubilities: Soluble in HCl, H2SO4, hot water, and alkalies, Insoluble in water.
-Vapor Pressure: 1 mm Hg at 1284 deg C
-Odor: Odorless
- Color/Form: Silver white ductile metal, cubic

Test animals

Species:

other: rats, hamsters, guinea pigs

Strain:

not specified

Sex:

male/female

Administration / exposure

Route of administration:

inhalation

Type of inhalation exposure:

whole body

Vehicle:

air

Details on inhalation exposure:

Aluminium oxide dust was used as a negative control. Two chambers, containing 30 rats and 30 hamsters each, were held at dust concentrations of 100 mg/m3of the pyro powder and the atomized metal powder respectively, two additional chambers were held 50 mg/m3of the respective powders. Six chambers, each containing 30 rats and 15 guinea pigs, were maintained at dust concentrations of 15 and 30 mg/m3respectively, for each of the three types of metallic aluminium powders. The animals were exposed for 6 hr daily, 5 days each week, for 6 months for the 50 and 100 mg/m3groups, and for 12 months for all other animals. An additional group of 30 rats and 30 hamsters was exposed to aluminium oxide dust at an average concentration of 75 mg/m3 for 6 months, and 30 rats and 12 guinea pigs were exposed to aluminium oxide at a concentration of 30 mg/m3 for one year.
Intratracheal injection of the aluminium powders at different dose levels was also conducted.

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

6 months; some animals were exposed for 1 year.

Frequency of treatment:

Animals were exposed for 6 hr/day, 5 days/week, for 6
months; some animals were exposed for 1 year.

Doses / concentrations

Remarks:

Doses / Concentrations:
15, 30, 50 , 75 , 100 mg/m3,
Basis:
nominal conc.

No. of animals per sex per dose:

Two chambers, containing 30 rats and 30 hamsters each, Six chambers, each containing 30 rats and 15 guinea pigs, group of 30 rats and 30 hamsters , and group of 30 rats and 12 guinea pigs .

Control animals:

yes

Details on study design:

Rats, guinea pigs, and hamsters were exposed to 3 different types of aluminium powder (British pyro powderflake like particles, American powder with flake like particles, and powder comprised of atomized spherical particles) in inhalation chambers at varying concentrations.
Animals were exposed for 6 hr/day, 5 days/week, for 6 months; some animals were exposed for 1 year

Examinations

Observations and examinations performed and frequency:

Histological examination of the lungs
All three species of animals developed alveolar proteinosis, the severity and extent of which were not consistently or clearly related either to the type of aluminium powder or to the severity of the dust exposure. The alveolar proteinosis resolved spontaneously and the accumulated dust deposits cleared rapidly from the lungs after cessation of exposure. Intratracheal injection of large doses of aluminium powders into rats produced focal pulmonary fibrosis; no fibrosis occurred in the lungs of hamsters following intratracheal injection.

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

not examined

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

effects observed, treatment-related

Haematological findings:

effects observed, treatment-related

Clinical biochemistry findings:

effects observed, treatment-related

Urinalysis findings:

effects observed, treatment-related

Behaviour (functional findings):

effects observed, treatment-related

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

effects observed, treatment-related

Details on results:

Pulmonary fibrosis was not apparent following inhalation of the aluminium powders in hamsters and guinea pigs; however scattered small scars resulted from foci of lipid pneumonitis in rats.
All three species of animals developed alveolar proteinosis, the severity and extent of which were not consistently or clearly related either to the type of aluminium powder or to the severity of the dust exposure. The alveolar proteinosis resolved spontaneously and the accumulated dust deposits cleared rapidly from the lungs after cessation of exposure. Intratracheal injection of large doses of aluminium powders into rats produced focal pulmonary fibrosis; no fibrosis occurred in the lungs of hamsters following intratracheal injection.

Effect levels

1

Dose descriptor:

NOAEC

Effect level:

15 mg/m³ air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: see 'Remark'

2

Dose descriptor:

NOAEC

Effect level:

30 mg/m³ air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: see 'Remark'

3

Dose descriptor:

NOAEC

Effect level:

50 mg/m³ air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: see 'Remark'

4

Dose descriptor:

NOAEC

Effect level:

75 mg/m³ air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: overall effects Pulmonary fibrosis was not apparent following inhalation of the aluminium powders in hamsters and guinea pigs; however scattered small scars resulted from foci of lipid pneumonitis in rats.

5

Dose descriptor:

NOAEC

Effect level:

100 mg/m³ air

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: overall effects Pulmonary fibrosis was not apparent following inhalation of the aluminium powders in hamsters and guinea pigs; however scattered small scars resulted from foci of lipid pneumonitis in rats.

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

The results of this experiment indicate that inhalation of fine metallic aluminium powders does not produce fibrogenic effects, and that intratracheal injection of these powders is likely an artefact of the injection itself.

Executive summary:

The fibrogenic potential of very fine metallic aluminium powder was investigated byGross et al. (1973). Three different types of aluminium powder were tested. Pyro powder and flaked powder were composed of flake-like particles, and the atomized powder consisted of atomized spherical particles.

Aluminium oxide dust was used as a negative control. Two chambers, containing 30 rats and 30 hamsters each, were held at dust concentrations of 100 mg/m³of the pyro powder and the atomized metal powder respectively, two additional chambers were held 50 mg/m³of the respective powders. Six chambers, each containing 30 rats and 15 guinea pigs, were maintained at dust concentrations of 15 and 30 mg/m³respectively, for each of the three types of metallic aluminium powders. The animals were exposed for 6 hr daily, 5 days each week, for 6 months for the 50 and 100 mg/m³groups, and for 12 months for all other animals. An additional group of 30 rats and 30 hamsters was exposed to aluminium oxide dust at an average concentration of 75 mg/m³for 6 months, and 30 rats and 12 guinea pigs were exposed to aluminium oxide at a concentration of 30 mg/m³for one year.

Intratracheal injection of the aluminium powders at different dose levels was also conducted.

 

Pulmonary fibrosis was not apparent following inhalation of the aluminium powders in hamsters and guinea pigs; however scattered small scars resulted from foci of lipid pneumonitis in rats.

All three species of animals developed alveolar proteinosis, the severity and extent of which were not consistently or clearly related either to the type of aluminium powder or to the severity of the dust exposure. The alveolar proteinosis resolved spontaneously and the accumulated dust deposits cleared rapidly from the lungs after cessation of exposure. Intratracheal injection of large doses of aluminium powders into rats produced focal pulmonary fibrosis; no fibrosis occurred in the lungs of hamsters following intratracheal injection.

The results of this experiment indicate that inhalation of fine metallic aluminium powders does not produce fibrogenic effects, and that intratracheal injection of these powders is likely an artefact of the injection itself.