P 16513

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in mammalian cells

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2007

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)

Deviations:

no

GLP compliance:

yes

Type of assay:

mammalian cell gene mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Strontium 4-chloro-2-[2-hydroxy-6-sulfonatonaphthalen-1-yl)diazenyl]benzoate

Cas Number:

474814-88-5

Molecular formula:

C17H9ClN2O6SSr

IUPAC Name:

Strontium 4-chloro-2-[2-hydroxy-6-sulfonatonaphthalen-1-yl)diazenyl]benzoate

Test material form:

solid: nanoform, no surface treatment

Method

Target gene:

Thymidine Kinase Locus (TK+/-) in Mouse Lymphoma L5178Y Cells

Species / strain

Species / strain / cell type:

mouse lymphoma L5178Y cells

Metabolic activation:

with and without

Metabolic activation system:

rat liver S9

Test concentrations with justification for top dose:

Pre-Test: 2.3, 4.7, 9.4, 18.8, 37.5, 75, 150, 300µg/ml with and without S9 mix
Experiment I: 18.8, 37.5, 75, 150, 300, 600 µg/ml with and without S9 mix;
Experiment II: 18.8, 37.5, 75, 150, 300, 600 µg/ml with and without S9 mix;

Vehicle / solvent:

DMSO

Controls

Controls 1

Positive controls:

yes

Positive control substance:

cyclophosphamide

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Controls 3

Untreated negative controls:

yes

Negative solvent / vehicle controls:

other: medium

Controls 4

Positive controls:

yes

Positive control substance:

methylmethanesulfonate

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium;

DURATION
- Exposure duration: 4, and 24 h
- Expression time (cells in growth medium): 48 to 72 h;
- Selection time (if incubation with a selection agent): approximately 11 d

NUMBER OF REPLICATIONS: 2

NUMBER OF CELLS EVALUATED: approximately 4000

DETERMINATION OF CYTOTOXICITY
Relative Suspension Growth

OTHER EXAMINATIONS:
- Determination of mutant colony numbers
-small mutant colonies
-large mutant colonies

Evaluation criteria:

standard

Statistics:

A linear regression (least squares) was performed to assess a possible dose dependent increase of mutant frequencies using SYSTAT 11 software. The number of mutant colonies obtained for the groups treated with the test item was compared to the solvent control groups.

Results and discussion

Test results

Species / strain:

mouse lymphoma L5178Y cells

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:

Precipitation at max. dose (600 µg/ml) visible even by naked eye;
COMPARISON WITH HISTORICAL CONTROL DATA: y

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

the test item did not induce mutations in the mouse lymphoma thymidine kinase locus assay using the cell line L5178Y in the absence and in the presence of metabolic activation; No substantial and reproducible dose dependent increase in mutant colony numbers was observed. No relevant shift of the ratio of small versus large colonies occurred.
The substance is not subject of classification and labelling