Zinc distearate

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Justification for type of information:

Data is from NTRL

Data source

Reference

Reference Type:

secondary source

Title:

MUTAGENICITY EVALUATION OF FDA 75-72 ZINC STEARATE USP(000557-05-1)

Author:

Brusick DJ

Year:

1977

Bibliographic source:

LITTON BIONETICS, INC. '5516 NICHOLSON LANE KENSINGTON, MARYLAND 20795 LBI PROJECT NO. 2672, NATIONAL TECHNICAL INFORMATION SERVICE ,SPRINGFIELD,VA,22161

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: As mention below

Principles of method if other than guideline:

The objective of this study was to evaluate-the test compaund) for genetic activity in microbial assays with and without the addition of mammalian metabolic activation preparations.

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Zinc distearate

EC Number:

209-151-9

EC Name:

Zinc distearate

Cas Number:

557-05-1

Molecular formula:

C18H36O2.1/2Zn

IUPAC Name:

zinc distearate

Details on test material:

- Name of test material: Zinc Distearate (ZDS)
- Molecular formula: C18H36O2.1/2Zn
- Molecular weight: 632.3476 g/mol
- Substance type: Organic
- Physical state: Solid (Free flowing white Powder)
- Impurities (identity and concentrations): 0.14 %

Method

Target gene:

Histidine

Species / strain

Species / strain / cell type:

S. typhimurium, other: TA 1535, TA 1537, TA 1538 ,TA 98 and TA 100

Details on mammalian cell type (if applicable):

Not specified

Additional strain / cell type characteristics:

not specified

Cytokinesis block (if used):

not specified

Metabolic activation:

with and without

Metabolic activation system:

The tissue homogenates and 9,000 x g supernatants were prepared from tissues of the following mammalian species: Mouse - ICR random bred adult males; at - Sprague-Dawley adult males; and monkey - Macaca mulatta adult males

Test concentrations with justification for top dose:

O. 115, 0.0575 and 0.02875%

Vehicle / solvent:

Vehicle
- Vehicle(s)/solvent(s) used: N, N-Dimethyl Formamide
- Justification for choice of solvent/vehicle: Test chemical was soluble in DMF

Controls

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

yes

Remarks:

N, N-Dimethyl Formamide

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

other: -S9;Methylnitrosoguanidine Ethylmethanesulfonate 2-Nitrofluorene Quinacrine mustard +S9; Dimethylnitrosamine 2-Acetylaminofluorene 8-Aminoquinoline 2-Aminoanthracene

Details on test system and experimental conditions:

Details on test system and conditions
METHOD OF APPLICATION;

Experiment I; Plate Tests(overlay method)
Experiment II; Suspension Tests

DURATION
Experiment I;
- Exposure duration:48 to 72 hours

Experiment II;
- Preincubation period: 1 hour
- Exposure duration:48 hours


DETERMINATION OF CYTOTOXICITY
- Method; relative total growth

Evaluation criteria:

Evaluation Criteria for Ames Assay
Because the procedures used to evaluate the mutagenicity of the test chemicalwere semi quantitative. the criteria used to determine positive effects are
inherently subjective and are based primarily on a historical data base. Most data sets are evaluated using the following criteria:
1. Strains TA-1535. TA-1537. and TA-1538
If the solvent control value is within the normal range. a chemical that produces a positive dose response over three concentrations with the lowest increase equal to twice the solvent control value is considered to be mutagenic.
2. Strains TA-98. TA-100. and 04
If the solvent control value is within the normal range. a chemical that produces a positive dose response over three concentrations with the highest increase equal to twice the solvent control value for TA-100 and two to three times the solvent control value for strains TA-98 and 04 is considered to be mutagenic. For these strains. the dose response increase should start at approximately the solvent control value.
3. Pattern
Because TA-1535 and TA-100 were both derived from the same parental strain (G46) and because TA-l~38 and TA-98 were both derived from the same parental strain (03052). There is a built-in redundancy in the microbial assay. In general the two strains of a set respond to the same mutagen and such a pattern is sought. It is also anticipated that if a given strain, e.g. TA1537,responds to a mutagen in nonactivation tests it will generally do so in activation tests. (The converse of this relationship is not expected.) While similar response patterns are not required for all mutagens. they can be used to enhance the reliability of an evaluation decision.

Statistics:

Yes

Results and discussion

Test results

Key result

Species / strain:

S. typhimurium, other: Salmonella typhimurium TA 1535, TA 1537, TA 1538 ,TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

not specified

Positive controls validity:

valid

Remarks on result:

other: No mutagenic effects were observed

Applicant's summary and conclusion

Conclusions:

Zinc Distearate was observed for its mutagenic potential in Salmonella typhimurium TA 1535, TA 1537, TA 1538 ,TA 98 and TA 100 by plate assay and suspension tests in the presence and absence of S9. The test result was considered to be non mutagenic in both the test.

Executive summary:

In genetic toxicity study Zinc Distearate was assessed for its possible mutagenic potential by In vitro bacterial gene mutation assay. The test was performed inSalmonella typhimurium TA 1535, TA 1537, TA 1538 ,TA 98 and TA 100 by plate assay and suspension tests in the presence and absence of S9 . The test substance was exposed at the concentration of O. 115, 0.0575 and 0.02875%.No mutagenic effects were observed in both the assayin the presence and absence of S9.Therefore test substance was considered to be non-mutagenic with and without metabolic activation inSalmonella typhimurium TA 1535, TA 1537, TA 1538 ,TA 98 and TA 100.Hence the substance cannot be classified as gene mutant in vitro.