Registration Dossier

Toxicological information

Genetic toxicity: in vitro

Currently viewing:

Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Remarks:
Type of genotoxicity: gene mutation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2006
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study was conducted according to GLP and valid methods, therefore it is considered adequate, reliable and relevant for classification.
Cross-reference
Reason / purpose:
reference to same study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2006
Report Date:
2006

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)
Deviations:
no
Principles of method if other than guideline:
Not applicable.
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
- Name of test material (as cited in study report): Chloramin B; sodium N-chlorobenzenesulphonamide trihydrate
- Substance type: Biocide
- Physical state: White to light yellow powder
- Analytical purity: 98%
- Impurities (identity and concentrations): 0.6% NaOH.
- Composition of test material, percentage of components: 77% CAS 127-52-6 (98% pure), 22.4% Water incl. trihydrate, 0.6% NaOH.
- Isomers composition: Not applicable
- Purity test date: No data
- Lot/batch No.: 54/MA/20/06.
- Expiration date of the lot/batch: 03/2011.
- Stability under test conditions: Stable, c.f. Chapter 4.18.
- Storage condition of test material: Stable, c.f. Chapter 4.18.

Method

Target gene:
Histidine; Tryptophan
Species / strainopen allclose all
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Details on mammalian cell lines (if applicable):
- Type and identity of media: Nutrient broth Merck; Agar-agar Fluka
- Properly maintained: yes

- Periodically "cleansed" against high spontaneous background: yes/no
Metabolic activation:
with and without
Metabolic activation system:
S9-mix
Species / strain:
E. coli WP2 uvr A
Metabolic activation:
with and without
Metabolic activation system:
S9-mix
Test concentrations with justification for top dose:
First toxicity test: 0, 10, 100, 500, 1000, 2500 and 5000µg/plate
Second toxicity test: 0, 1, 5, 10, 25, 50 and100 µg/plate
First mutagenicity test: 0, 1, 3, 10, 30 and 100 µg/plate
Second mutagenicity test: 0, 0.3, 1, 3, 10 and 30 µg/plate (due to the substance´s toxicity lower doses were chosen for the repeated test)
Vehicle:
- Vehicle(s)/solvent(s) used: demineralized water
- Justification for choice of solvent/vehicle:
Controlsopen allclose all
Negative controls:
yes
Remarks:
without solvent
Solvent controls:
yes
Remarks:
0.1mL demineralized water
Positive controls:
yes
Positive control substance:
sodium azide
Remarks:
1.5 µg/plate TA 100 and TA 1535
Negative controls:
yes
Remarks:
without solvent
Solvent controls:
yes
Remarks:
0.1mL demineralized water
Positive controls:
yes
Positive control substance:
other: 4-nitro-o-phenylenediamine
Remarks:
20 µg/plate TA 98
Negative controls:
yes
Remarks:
without solvent
Solvent controls:
yes
Remarks:
0.1mL demineralized water
Positive controls:
yes
Positive control substance:
other: 9-aminoacridine hydrochloride monohydrate
Remarks:
100 µg/plate TA 1537
Negative controls:
yes
Remarks:
without solvent
Solvent controls:
yes
Remarks:
0.1mL demineralized water
Positive controls:
yes
Positive control substance:
other: 2-aminofluorene
Remarks:
10µg/plate TA100 and TA98
Negative controls:
yes
Remarks:
without solvent
Solvent controls:
yes
Remarks:
0.1mL demineralized water
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene
Remarks:
1.0µg/plate –TA 1535, 2.5µg/plate –TA 1537, 25 µg/plate – E.coli
Negative controls:
yes
Remarks:
without solvent
Solvent controls:
yes
Remarks:
0.1mL demineralized water
Positive controls:
yes
Positive control substance:
other: N-methyl-N’-nitro-N-nitrosoguanidine
Remarks:
20µg/plate E. Coli
Details on test system and conditions:
METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48-72h (exposure time in selection medium)
- Selection time (if incubation with a selection agent): 48-72h

SELECTION AGENT (mutation assays): histidine; tryptophan

NUMBER OF REPLICATIONS: Triplicate

DETERMINATION OF CYTOTOXICITY
- Method: decrease in number of revertants, changes in background

Evaluation criteria:
The main criterion for the evaluation of results was the modified two-fold increase rule, its using is comparable with using of statistical methods. After this rule the result is positive, when reproducible dose-effect and/or doubling of ratio of number of revertants at tested dose to number of revertants in negative control (Rt/Rc ) is reached.

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:
yes
Vehicle controls valid:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.
Additional information on results:
Cytotoxicity at 100 µg/plate

Applicant's summary and conclusion

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

In the arrangement given above, the test substance Chloramin B trihydrate was nonmutagenic for all used bacterial strains with as well as without metabolic activation.
Executive summary:

The test Substance Chloramin B trihydrate was assayed for the mutagenicity by the Bacterial Reverse Mutation Test. The test was performed according to OECD Test Guideline 471 Bacterial Reverse Mutation Test which is analogous to the EU method B.13/14. Four indicator Salmonella typhimurium strains TA 98, TA 100, TA 1535 and TA 1537 and one indicator Escherichia coli WP2uvrA strain were used. The test substance was dissolved in demineralized water and assayed in doses of 0.3-100 µg which were applied to the plates in emulsion in amount of 0.05 mL. Two series of experiments were performed with each strain- without metabolic activation and with supernatant of rat liver and a mixture of cofactors. In the arrangement given above, the test substance Chloramin B trihydrate was nonmutagenic for all used bacterial strains with as well as without metabolic activation.