Barium chromate

Repeated dose toxicity: inhalation

Administrative data

Endpoint:

sub-chronic toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well reported literature study, but non-standard design. Findings are consistent with those in other similar studies.

Data source

Reference

Reference Type:

publication

Title:

Effects of chromium compounds an the respiratory system.

Author:

Adachi, S., Yoshimura, H., Katayama, H., Takemoto, K.

Year:

1986

Bibliographic source:

Jpn J Ind Hlth 28, 283 – 287, 1986

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Respiratiry tract toxicity was investigated following repeated inhalation exposure to chromic acid mist for two 30 minute periods a week for 6-12 months.

GLP compliance:

no

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Chromium

EC Number:

231-157-5

EC Name:

Chromium

Cas Number:

7440-47-3

Molecular formula:

Cr

IUPAC Name:

chromium

Specific details on test material used for the study:

Mice were exposed to aqueous solutions of chromium trioxide (chromic acid (mist)). No further details are given.

Test animals

Species:

mouse

Strain:

ICR

Sex:

female

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

whole body

Vehicle:

other: water, chromic acid is aqueous chromium trioxide

Remarks on MMAD:

MMAD / GSD: 85% of the mist particles are reported to have been <5um diameter and 97% were <10 um diameter.

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

Mice were exposed for two periods of 30 minutes per week, for 6-12 months.

Frequency of treatment:

Mice were exposed for two periods of 30 minutes per week, for 6-12 months

Doses / concentrations

Dose / conc.:

3.63 mg/m³ air (analytical)

No. of animals per sex per dose:

Exposed animals were terminated at 6-9 months (15 mice), 10-14 months (14 mice) and all remaining animals at 15-18 months (19 mice). Control
animals (10) were terminated at 12 and 18 months.

Control animals:

yes, concurrent no treatment

Results and discussion

Effect levels

Dose descriptor:

LOAEC

Effect level:

3.63 mg/m³ air

Sex:

female

Basis for effect level:

other: Single exposure level: irritant and corrosive effects

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

Irritant and corrosive effects in the respiratory tract (perforated nasal septum, tracheal and bronchial epithelial hyperplasia, emphysema) occurred in treated animals.

Applicant's summary and conclusion

Conclusions:

Exposure to chromic acid mist at the exposure level equivalent to 3.63 mg Cr/m3 for 6-12 months was found to induce changes consisitent with irritation and corrosion in the respiratory tract of female mice.

Executive summary:

Female ICR mice were exposed to chromic acid mist at a concentration equivalent to 3.63 mg Cr/m3 for two 30 -minute periods a week for 6 -12 months. Exposure was found to induce changes consisitent with irritation and corrosion in the respiratory tract.