Tin difluoride

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Justification for type of information:

After dissolution and disociation in environmental (aqueous)/physiolological media the constituents of tin difluoride become bioavailable and the overall toxicity of the dissociated substance can be described by the toxicity of the individual constituents/ions. Since synergistic effects are not to be expected, the human health and environmental hazard assessment of the assessment entity tin difluoride consists of an individual assessment of the assessment entities tin cation and the fluoride anion. The tin cation and the fluoride anion are considered to represent the overall toxicity of tin difluoride in a manner proportionate to the fluoride and the metal (represented by one of its readily soluble salts). Based on the above information, unrestricted read-across is considered feasible and justified.

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Reference 2

Reference Type:

publication

Title:

Salmonella mutagenicity test results for 250 chemicals

Author:

Haworth, S. et al.

Year:

1983

Bibliographic source:

Environmental Mutagenesis, Supplement 1: 3 - 142.

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Ames Salmonella/mammalian microsome test

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Sodium fluoride

EC Number:

231-667-8

EC Name:

Sodium fluoride

Cas Number:

7681-49-4

IUPAC Name:

sodium fluoride

Details on test material:

- Name of test material (as cited in study report): sodium fluoride
- Analytical purity: 99%
- Lot/batch No.: DC 030887

Method

Species / strain

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254-induced male Sprague-Dawley rat or Syrian hamster liver S9

Test concentrations with justification for top dose:

0, 100, 333, 1000, 3333 and 10000 ug NaF/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: Dimethylsulfoxide

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Remarks:

dimethylsulfoxide (DMSO)

Positive controls:

yes

Positive control substance:

9-aminoacridine

sodium azide

other: 2-aminoanthracene and 4-nitro-o-phenylenediamine

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation); refer to Haworth (1983) for details

DURATION
- Preincubation period: 20 minutes at 37 °C
- Exposure duration: 48 hours

NUMBER OF REPLICATIONS: Two

Evaluation criteria:

A positive response was defined as a reproducible, dose-related increase in histidine-independent (revertant) colonies in any one strain/activation combination. An equivocal response was defined as an increase in revertants that was not dose-related, not reproducible, or of insufficient magnitude to support a determination of mutagenicity. A negative response was obtained when no increase in revertant colonies was observed following chemical treatment.

Statistics:

Revertants were presented as mean ± the SD from 3 plates.

Results and discussion

Test results

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

Sodium fluoride did not induce gene mutations in any of the strains of Salmonella typhimurium tested.
Definitive cytotoxicity was not observed in any Salmonella typhimurium strains at doses up to 10,000 ug/plate

Applicant's summary and conclusion

Conclusions:

Sodium fluoride did not induce gene mutations in Salmonella typhimurium strains TA100, TA1535, TA1537 and TA98 when tested with a preincubation protocol at doses of 100 to 10,000 ug/plate. All strians were tested with or without Aroclor 1254-induced male Sprague-Dawley or Syrian hamster liver S9.