Tin dioxide

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1992

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Published data fulfilled basically scientific principles.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1992

Report date:

1991

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

The experimental procedures for the SOS chromtest were mainly based on what was established by Quillard and Hofnung (1985).
The SOS Chromotest is able to detect DNA damage by the measurement of induction of sfiA, which is a gene controlled by the general repressor of the SOS system in E.Coli.

GLP compliance:

no

Type of assay:

other: SOS Chromtest

Test material

Test material information

Constituent 1

Reference substance name:

Tin chloride

EC Number:

215-689-5

EC Name:

Tin chloride

Cas Number:

1344-13-4

IUPAC Name:

tin(4+) tetrachloride

Details on test material:

Test material as cited in the publication: inorganic tin (SnCl4) as analytical grade was supplied from Hayashi Pure Chemical Co.

Method

Species / strain

Species / strain / cell type:

E. coli, other: PQ37

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

without

Test concentrations with justification for top dose:

The experiment was performed at a concentration of chemical at which a decrease of the activity of alkaline phosphatase was observed.
The test item was used at a concentration ranging from 10 tp 1010^4 µg/plate.

Controls

Untreated negative controls:

yes

Remarks:

DMSO

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 1535

Remarks:

Not determinated

Metabolic activation:

not applicable

Genotoxicity:

not determined

Cytotoxicity / choice of top concentrations:

not determined

Vehicle controls validity:

not applicable

Untreated negative controls validity:

not applicable

True negative controls validity:

not applicable

Positive controls validity:

not applicable

Test results 2

Species / strain:

S. typhimurium TA 1537

Remarks:

Not determinated

Metabolic activation:

not applicable

Genotoxicity:

not determined

Cytotoxicity / choice of top concentrations:

not determined

Vehicle controls validity:

not applicable

Untreated negative controls validity:

not applicable

True negative controls validity:

not applicable

Positive controls validity:

not applicable

Test results 3

Species / strain:

S. typhimurium TA 98

Remarks:

Not determinated

Metabolic activation:

not applicable

Genotoxicity:

not determined

Cytotoxicity / choice of top concentrations:

not determined

Vehicle controls validity:

not applicable

Untreated negative controls validity:

not applicable

True negative controls validity:

not applicable

Positive controls validity:

not applicable

Test results 4

Species / strain:

S. typhimurium TA 100

Remarks:

Not determinated

Metabolic activation:

not applicable

Genotoxicity:

not determined

Cytotoxicity / choice of top concentrations:

not determined

Vehicle controls validity:

not applicable

Untreated negative controls validity:

not applicable

True negative controls validity:

not applicable

Positive controls validity:

not applicable

Test results 5

Species / strain:

E. coli WP2

Remarks:

Not determinated, PQ37 has been tested

Metabolic activation:

not applicable

Genotoxicity:

not determined

Cytotoxicity / choice of top concentrations:

not determined

Vehicle controls validity:

not applicable

Untreated negative controls validity:

not applicable

True negative controls validity:

not applicable

Positive controls validity:

not applicable

Test results 6

Key result

Species / strain:

E. coli, other:

Metabolic activation:

without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

The enzyme activities of alkaline phosphatase and ß-galactosidase were calculated with the following formula: Enzyme unit = 1000 x A420/t.

A420 is the optical density at 420 nm and it is the reaction time (90 min). Then the ratio ß-galactosidase units to alkaline phosphatase units (R(C)) was calculated and the induction factor (I(C)) was finally calculated thus: I(C) = R(C)/R(0). R(C) represents the value at concentration C, and R(0) is that at concentration 0. This induction factor (I(C)) expresses the SOS-inducing potency of the tested chemical.

When a significant increase in ß-galactosidase units of the tested chemical compared to that of the control was recognized by t-test (p < 0.05) and an enhancement of I(C) according to the increase of treated amount was shown, the chemical is considered as an SOS inducer.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative without metabolic activation