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Administrative data

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information
Calcium Iodate was found to be non genotoxic.
Link to relevant study records
Reference
Endpoint:
in vitro DNA damage and/or repair study
Remarks:
Type of genotoxicity: DNA damage and/or repair
Type of information:
migrated information: read-across based on grouping of substances (category approach)
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Qualifier:
according to
Guideline:
other:
Principles of method if other than guideline:
Cells were exposed for 3 h to concentrations of the test compounds of 0.625, 1.25, 2.5, 5 and 10 mM. Tests compound was dissolved in the culture medium. Etoposide (0.5 µg/ ml) was dissolved in DMSO.
After cells exposure to the test compounds for 3 h, the culture medium was discarded and replaced by fresh medium. Cells were incubated for 0.5, 1 or 24 h and DNA damage was measured at each sampling time by the alkaline comet assay.
GLP compliance:
not specified
Type of assay:
comet assay
Target gene:
no data
Species / strain / cell type:
Chinese hamster Ovary (CHO)
Details on mammalian cell type (if applicable):
Chinese hamster ovary (CHO-K1) cells were purchased from Eurobio (France). They were routinely maintained from stocks stored in liquid nitrogen. CHO cells were grown at 37 C in a humidified atmosphere at 5% CO2 in air, in HAM’S F12 medium with l-glutamine supplemented with 10% fetal calf serum (FCS), penicillin (50 UI/ml) and streptomycine (50 µg/ml). Cells were subcultured 24 h before treatment.
Additional strain / cell type characteristics:
not specified
Metabolic activation:
not specified
Test concentrations with justification for top dose:
0.625, 1.25, 2.5, 5 and 10 mM
Vehicle / solvent:
culture medium
Untreated negative controls:
yes
Negative solvent / vehicle controls:
not specified
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: Etoposide (0.5 µg/ml)
Species / strain:
Chinese hamster Ovary (CHO)
Metabolic activation:
not specified
Genotoxicity:
negative
Remarks:
The results showed that the comet assay failed to detect the presence of DNA damage after a treatment of cells by potassium iodate for concentrations up to 10 mM.
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
valid
Positive controls validity:
valid
Remarks on result:
other: strain/cell type: Chinese hamster ovary (CHO-K1) cells
Remarks:
Migrated from field 'Test system'.
Conclusions:
Interpretation of results (migrated information):
negative

Potassium iodate did not induce DNA damage in CHO cells when tested at concentrations up to 10 mM in alkaline comet assay.
Executive summary:

Potassium iodate did not induce DNA damage in CHO cells when tested at concentrations up to 10 mM in alkaline comet assay.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (negative)

Additional information

Additional information from genetic toxicity in vitro:

Genetic toxicity :

Based on the various studies available with Klimish rating 4 for read across substances considering weight of evidence approach.

The results is summarized as follows

 

Sr. No

End point

Effect

Species

 

Remarks

1

 DNA damage and repair

 

negative

 

 Chinese hamster Ovary (CHO)

 

Data is from publication for CAS NO 7758-05-6

2

 chromosome aberration

 

 negative

 

 chinese hamster Ovary (CHO)

 

Data is from publication for CAS NO 7758-05-6

3

 Gene mutation

 

negative

 mouse lymphoma L5178Y cells

 

Mammalian cell line Balb/c 3T3 cells

 

Data is from publication for CAS NO 7681-11-0

4

 Radiation-sensitizing effects on DNA

negative

  Marbourg strains of Bacillus subtilis

Data is from publication for CAS NO 7681-11-0

 

By applying weight of evidence approach to the studies summarized in the above table it can be concluded that the substanceCalcium iodate is not likely to exhibit positive genetic toxicity effect. Thus calcium iodate is considered to be non-mutagenic substance as per the CLP criteria.

 

 


Justification for selection of genetic toxicity endpoint
Potassium iodate did not induce DNA damage in CHO cells when tested at concentrations up to 10 mM in alkaline comet assay.

Justification for classification or non-classification

From the results obtained for calcium iodate it can be concluded that the substance Calcium iodate is not likely to exhibit positive genetic toxicity effect