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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro cytogenicity / chromosome aberration study in mammalian cells
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Justification for type of information:
As with all metal salts, the significance for toxicity is the presence of specific ions that will form when in solution or when in biological systems.
In the case of Cr III salts, the counter ion will have an effect on solubility and this is itself dependant on the type of media being used and in particular the pH of that media. It is generally accepted that in the case of metal salts, testing with salts that are soluble in the respective test media will ensure maximum exposure of the metal ions. This will include chlorides and nitrates as being more soluble and will indeed have relevance when dissolved in acid media, such as if ingested.Read-across to other chromium III salts is therefore considered valid as long as the exposure in the test system is greater than would be expected for the substance under review for registration.

Data source

Reference
Reference Type:
publication
Title:
Cytotoxic, mutagenic and clastogenic effects of industrial chromium compounds
Author:
P.Venier, A.MontaJdi, F.Majone, V.Bianchi and A.G.Levis
Year:
1982
Bibliographic source:
Carsinogenesls Vol.3 No.ll pp.1331-1338, 1982

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)
Version / remarks:
Old study - not performed to most recent guidelines
Principles of method if other than guideline:
Chromosomal aberrations and SCEs were used as parameters of dastogenicity. CHO cell cultures were treated for two division cycles (30 h)with Cr compounds in the presence of 3 x 10"' M bromodeoxyuridine (BUdR, Sigma). Chromosomal preparations were obtained and scored
GLP compliance:
no
Type of assay:
other: Chromosome aberration

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid
Details on test material:
No further information; laboratory grade
Specific details on test material used for the study:
LAboratory grade. Merck

Method

Species / strain
Species / strain:
Chinese hamster Ovary (CHO)
Controls
Negative controls:
yes
Details on test system and conditions:
The cells were incubated in vitro for two generation cycles with 3 x 10-5 M BUdR and/or 50 ug/ml Cr (III), as 10-3 M CrCl3
Rationale for test conditions:
These conditions were known to lead to positive effects with Cr VI
Evaluation criteria:
Chromosomal aberrations in metaphases

Results and discussion

Test results
Key result
Species / strain:
Chinese hamster Ovary (CHO)
Metabolic activation:
not specified
Genotoxicity:
negative
Cytotoxicity:
no
Negative controls valid:
yes

Applicant's summary and conclusion

Conclusions:
Negative.
Executive summary:

This research was mainly to compare Cr VI with Cr III and also examined 'contaminated' Cr based materials from industrial uses. The results add to the weight of evdience that Cr III is not mutagenic or cytotoxic.