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:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Study period:
11 - 22 March 2010
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
GLP - Guideline study tested with the source substance CAS 10043-01-3. According to the ECHA guidance document “Practical guide 6: How to report read-across and categories (March 2010)”, the reliability was changed from RL1 to RL2 to reflect the fact that this study was conducted on a read-across substance

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010
Report date:
2010

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Type of assay:
bacterial reverse mutation assay

Test material

Constituent 1
Chemical structure
Reference substance name:
Aluminium sulphate
EC Number:
233-135-0
EC Name:
Aluminium sulphate
Cas Number:
10043-01-3
Molecular formula:
Al.3/2H2O4S
IUPAC Name:
Aluminium sulphate
Details on test material:
- Name of test material (as cited in study report): NOTOX Substance 202030/A
- Substance type: white granules
- Physical state: solid
- Stability under test conditions: stable
- Storage condition of test material: at room temperature in the dark

Method

Target gene:
his (for S.Typhimurium strains)
trp (for E.coli strains)
Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Species / strain / cell type:
E. coli WP2 uvr A
Metabolic activation:
with and without
Metabolic activation system:
Cofactor supplemented post-mitochondrial fraction (S9-mix induced), prepared from livers of rats treated with a combination of phenobarbital and ß-naphthoflavone
Test concentrations with justification for top dose:
Experiment 1:
Preliminary test (without and with S9) TA100 and WP2uvrA: 3, 10, 33, 100, 333, 1000, 3330 and 5000 µg/plate

Main study: TA1535, TA1537 and TA98:
Without and with S9-mix: 100, 333, 1000, 3330 and 5000 µg/plate

Experiment 2:
Without and with S9-mix: 33, 100, 333, 1000, 3330 and 5000 µg/plate
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: water
- Justification for choice of solvent/vehicle: test compound was soluble in water and water has been accepted and approved by authorities and international guidelines
Controlsopen allclose all
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
sodium azide
Remarks:
without S9

Migrated to IUCLID6: 5 µg/plate in saline for TA1535
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
9-aminoacridine
Remarks:
without S9

Migrated to IUCLID6: 60 µg/plate in water for TA1537
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
2-nitrofluorene
Remarks:
without S9

Migrated to IUCLID6: 10 µg/plate in DMSO for TA98
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
methylmethanesulfonate
Remarks:
without S9

Migrated to IUCLID6: 650 µg/plate in DMSO for TA100
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
4-nitroquinoline-N-oxide
Remarks:
without S9

Migrated to IUCLID6: 10 µg/plate in DMSO for WP2uvrA
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene in DMSO for all tester strains
Remarks:
with S9
Details on test system and experimental conditions:
METHOD OF APPLICATION: in agar (plate incorporation)
DURATION
- Exposure duration: 48 hour
NUMBER OF REPLICATIONS:
- Doses of the test substance were tested in triplicate in each strain. Two independent experiments were conducted.
NUMBER OF CELLS EVALUATED: 10E8 per plate
DETERMINATION OF CYTOTOXICITY
- Method: the reduction of the bacterial background lawn, the increase in the size of the microcolonies and the reduction of the revertant colonies.
OTHER EXAMINATIONS:
- The presence of precipitation of the test compound on the plates was determined.
Evaluation criteria:
A test substance is considered negative (not mutagenic) in the test if:
a) The total number of revertants in tester strain TA100 is not greater than two (2) times the concurrent control, and the total number of revertants in tester strains TA1535, TA1537, TA98 or WP2uvrA is not greater than three (3) times the concurrent control.
b) The negative response should be reproducible in at least one independently repeated experiment.
A test substance is considered positive if:
a) A two-fold (TA100) or more or a three-fold (TA1535, TA1537, TA98, WP2uvrA) or more increase above solvent control in the mean number of revertant colonies is observed in the test substance group.
b) In case a repeat experiment is performed when a positive response is observed in one of the tester strains, the positive response should be reproducible in at least one independently repeated experiment.

Results and discussion

Test resultsopen allclose all
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:
cytotoxicity
Vehicle controls validity:
valid
Positive controls validity:
valid
Species / strain:
E. coli WP2 uvr A
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Positive controls validity:
valid
Additional information on results:
TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: no precipitation was observed up to and including the top dose of 5000 µg/plate
RANGE-FINDING/SCREENING STUDIES:
- toxicity was observed at the dose levels of 5000 μg/plate and above in the absence of S9-mix in tester strain TA100.

COMPARISON WITH HISTORICAL CONTROL DATA:
- the negative and strain-specific positive control values were within our laboratory historical control data ranges indicating that the test conditions were adequate and that the metabolic activation system functioned properly.

ADDITIONAL INFORMATION ON CYTOTOXICITY:
TA1535: without S9: 3330 µg/plate and above and with S9: 3330 µg/plate and above
TA1537: without S9: 1000 µg/plate and above and with S9: 3330 µg/plate and above
TA98: without S9: 1000 µg/plate and above and with S9: 5000 µg/plate and above
TA100: without S9: 3330 µg/plate and above
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

All bacterial strains showed negative responses over the entire dose range, i.e. no significant dose-related increase in the number of revertants in two independently repeated experiments.