Registration Dossier

Administrative data

Endpoint:
sub-chronic toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
abstract

Data source

Reference
Reference Type:
publication
Title:
Toxic effects of chromium boride and carbide in rats.
Author:
Roshhina T.A.
Year:
1967
Bibliographic source:
Novye Dannye po Toksikologii Redkikh Metallov i Ikh Soedinenii, 166-71

Materials and methods

Principles of method if other than guideline:
Not specified. Only english abstract of russian article available.

Test material

Reference
Name:
Unnamed
Type:
Constituent
Specific details on test material used for the study:
Not specified. Only english abstract of russian article available.

Test animals

Species:
rat
Strain:
not specified
Sex:
not specified
Details on test animals and environmental conditions:
Not specified. Only english abstract of russian article available.

Administration / exposure

Route of administration:
inhalation: dust
Type of inhalation exposure:
whole body
Remarks:
Latushkina chamber
Details on inhalation exposure:
Inhalation contamination of rats by CrB2 dust was made in the Latushkina chamber (3 months every other day by 2 hrs.) at conentrations of 300-50 mg/m³
Analytical verification of doses or concentrations:
not specified
Duration of treatment / exposure:
3 months, 2 hours/day
Frequency of treatment:
3 months, 2 hours/day
Doses / concentrations
Dose / conc.:
50 mg/m³ air
Remarks:
to 300 mg/m³
No. of animals per sex per dose:
not specified

Results and discussion

Results of examinations

Details on results:
The CrB2 and CrC had general toxic effect (decreases Hb content in blood), bronchitis, and cell prolifieration) with CrB2 acting more strongly. The intratracheal administering of CrC and CrB2 (50 mg) to rats caused changes in protein fractions of blood serum, and dust incapsulated foci, peribronchitis, perivascular and peribronchial sclerosis in lungs. The lung tissue reaction to the CrC and CrB2 was similar to that of chromite dust but was more strong. The CrC and CrB2 were less toxic than Cr anhydride and oxide.

Applicant's summary and conclusion

Conclusions:
The CrC and CrB2 were less toxic than Cr anhydride and oxide.
Executive summary:

Inhalation contamination of rats by CrB2 and CrC were made in the Latushkina chamber (exposure over 3 months on each day with 50-300 mg/m³). The CrB2 and CrC had general toxic effect (decreases Hb content in blood), bronchitis, and cell proliferation) with CrB2 acting more strongly. The intratracheal administering of CrC and CrB2 (50 mg) to rats caused changes in protein fractions of blood serum, and dust incapsulated foci, peribronchitis, perivascular and peribronchial sclerosis in lungs. The lung tissue reaction to the CrC and CrB2 was similar to that of chromite dust but was stronger. The CrC and CrB2 were less toxic than Cr anhydride and oxide.

Based on the lacking information on study design and study results the publication was assigned with a Klimisch score of 4 and will not be used for regulatory purposes.