aluminium-magnesium-carbonate-hydroxide-perchlorate-hydrate

Genetic toxicity: in vitro

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:

March 31, 1995 - April, 13, 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

(1983)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: European Economic Community (EEC), Directive 92/69/EEC. Annex V of the EEC Directive 67/548/EEC, Part B: Methods for the Determination of Toxicity; B.14: "Other Effects-Mutagenicity: Salmonella typhimurium Reverse Mutation Assay". (1992)

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

422-150-1

EC Name:

-

Cas Number:

212455-49-7

Molecular formula:

Mg4 Al2 (OH)12 (CO3)0-0.75 (ClO4)0.5-2.0

IUPAC Name:

Aluminium Magnesium Hydroxide, Carbonate Perchlorate

Test material form:

solid: particulate/powder

Details on test material:

- Appearance: white powder
- Storage condition of test material: at room temperature in the dark

Method

Target gene:

- S. typhimurium: Histidine gene

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:

Rat liver S9-mix induced by Aroclor 1254 (500 mg/kg bw).

Test concentrations with justification for top dose:

Experiment 1
Preliminary test (without and with S9) TA100: 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: All 4 strains
Without and with S9-mix: 100, 333, 1000, 3330 and 5000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: Test compound was suspended or dissolved in DMSO and DMSO has been accepted and approved by authorities and international guidelines.

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

methylmethanesulfonate

Remarks:

without S9 Migrated to IUCLID6: 650 µg/plate in DMSO for TA100

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

other: daunomycine 4 µg/plate in saline for TA98

Remarks:

without S9

Controls 3

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

other: 9-aminoacridine 60 µg/plate in saline for TA1537

Remarks:

without S9

Controls 4

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

other: sodium azide 1 µg/plate in saline for TA1535

Remarks:

without S9

Controls 5

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene 5 µg/plate in DMSO for TA1535 and TA1537, and 0.5 µg/plate in DMSO for TA98 and TA100.

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 any tester strain at any concentration is not greater than two (2) times the concurrent control, with or without metabolic activation.
b) The negative response should be reproducible in at least one independently repeated experiment.

A test substance is considered positive if:
a) It induces at least a two-fold, dose related increase in the number of revertants with respect to the number induced by the solvent control in any of the tester strains, either with or without metabolic activation. However, any mean plate count of less than 20 is considered to be not significant. If in the first test the test substance showed only a positive response at one or two concentrations, the assay was repeated with doses just below and exceeding those showing positive effects in the first test.
b) The positive response should be reproducible in at least one independently repeated experiment.

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:

cytotoxicity

Remarks:

In both experiments a clear decrease in the number of revertants in strains TA100 and TA1537 in the absence of S9-mix was observed.

Vehicle controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: Precipitation was observed in the top agar at dose levels of 1000 µg/plate and upwards but precipitation was not observed at the end of the incubation period.

RANGE-FINDING/SCREENING STUDIES:
- No reduction of the bacterial background lawn was observed. A dose-related decrease was observed in the number of revertants.

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:
The bacterial background lawn was not reduced at all concentrations tested. In both experiments a clear decrease in the number of revertants in strains TA100 and TA1537 in the absence of S9-mix was observed.

Applicant's summary and conclusion

Conclusions:

Alcamizer 5 is not mutagenic in the Salmonella typhimurium reverse mutation assay, performed according to OECD 471 guideline and GLP principles with or without metabolic activation.

Executive summary:

The genetic toxicity of Alcamizer 5 was assessed using Salmonella typhimurium TA98, TA100, TA1535 and TA1537 strains, in accordance with OECD 471 guideline and GLP principles. No precipitation was observed at the end of the incubation period. The bacterial background lawn was not reduced at all concentrations tested. In both experiments a clear decrease in the number of revertants in strains TA100 and TA1537 in the absence of S9-mix was observed. All bacterial strains showed negative responses up to 5000 µg/plate, i.e. no biologically significant dose-related increase in the number of revertants with or without metabolic activation was seen in two independently repeated experiments. The negative and strain-specific positive control values were within the laboratory historical control data ranges indicating that the test conditions were adequate and that the metabolic activation system functioned properly. Based on the results of this study it is concluded that Alcamizer 5 is not mutagenic in the Salmonella typhimurium reverse mutation assay with or without metabolic activation.