Pentazinc chromate octahydroxide

Repeated dose toxicity: inhalation

Administrative data

Endpoint:

chronic toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: read-across from a slightly water soluble chromate

Cross-reference

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

publication

Title:

Morphogenesis of alveolar bronchiolization.

Author:

Nettesheim, P. and A. K. Szakal

Year:

1972

Bibliographic source:

Lab Invest.26(2): 210-9.

Materials and methods

Principles of method if other than guideline:

Chronic inhalation toxicity test: mice were exposed to test substance dust 5 and a half hour per day, 5 days per week, for 18 months.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Calcium chromate

EC Number:

237-366-8

EC Name:

Calcium chromate

Cas Number:

13765-19-0

IUPAC Name:

calcium dioxido(dioxo)chromium

Details on test material:

calcium chromate (CaCrO4) dust, ozonized gasoline fume

Test animals

Species:

mouse

Administration / exposure

Route of administration:

inhalation: dust

Type of inhalation exposure:

whole body

Duration of treatment / exposure:

18 months

Frequency of treatment:

5 and a half hours a day, 5 days a week

Doses / concentrations

Remarks:

Doses / Concentrations:
13 mg/m3 of calcium chromate
Basis:
nominal conc.

Examinations

Other examinations:

bacteriologic, virologic, and parasitologic testing

Results and discussion

Results of examinations

Clinical signs:

not examined

Mortality:

not examined

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:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

not specified

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

no effects observed

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

a concentration of 13 mg/m³of calcium chromate tested: non-carcinogenic morphological changes seen, no NOAEL identified

Applicant's summary and conclusion

Conclusions:

Non-cancerous morphological changes in the lower respiratory tract.

Executive summary:

Nettesheim et al. (1972) exposed mice (C57BL/6) to filtered air, ozonized gasoline fumes or calcium chromate dust (mean geometric diameter 0.2 μm) for five and a half hours/day, five days/week. The dust was dispensed into the inlet air at a concentration of 13 mg/m³. Eighteen months after the start of the exposure, 15 mice were removed from each chamber and used for bacteriologic, virologic, and parasitologic testing and for histopathology. Results showed necrosis and hyperplasia of the bronchial and alveolar epithelia, inflammation of the underlying bronchial and bronchiolar connective tissues, and hyperplasia or atrophy of surrounding lymph nodes.