Dipotassium dodecenylsuccinate

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:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Dipotassium dodecenylsuccinate

EC Number:

260-612-0

EC Name:

Dipotassium dodecenylsuccinate

Cas Number:

57195-28-5

Molecular formula:

C16H26K2O4*H2O

IUPAC Name:

Dipotassium dodecenylsuccinate

Test material form:

liquid

Details on test material:

30 % aqueous solution
pure substance is solid (bulk/powder), but is only used as aqueous solution and blends it into mixture
Substance dissolves in water at 40wt%, then becomes gel and becomes solid, if mixed 61wt% with water

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 170727
- Expiration date of the lot/batch: 2019/7/27
- Purity test date: 100%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature
- Stability under test conditions: stable
- Solubility and stability of the test substance in the solvent/vehicle: soluble in water

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Final dilution of a dissolved solid, stock liquid or gel: Based on the information provided by sponsor, the test item was dissolved in water. The test substances were prepared by dissolving the test item in water at different concentrations.

Method

Target gene:

His (Salmonella)
Trp (E.coli)

Species / strain

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2

Metabolic activation:

with and without

Metabolic activation system:

A co-factor supplemented post-mitochondrial fraction (S9) from the liver of Aroclor 1254 induced Sprague-Dawley rats was used as metabolic activation system.

Test concentrations with justification for top dose:

- Preliminary Test: 1) 5.0 mg / plate, 2) 1.5 mg / plate, 3) 0.46 mg / plate, 4) 0.14 mg / plate, 5) 0.04 mg / plate, 6) 0.01 mg / plate
- Main Test: 1) 5.0 mg / plate, 2) 2.5 mg / plate, 3) 1.25 mg/ plate, 4) 0.63 mg / plate, 5) 0.31 mg / plate

Vehicle / solvent:

water

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

2-nitrofluorene

sodium azide

benzo(a)pyrene

other: (1) 2-Aminoanthracene; (2) ICR 191

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar - minimal glucose agar base (1.5% agar, Vogel-Bonner E Medium with 2% glucose) was used for each plate.

0.1 ml of a fresh over-night culture of the test strain, 0.1 ml of the test substance at 6 concentrations / negative control / positive control, 0.2 ml Biotin/Histidine (For Salmonella typhimurium TA98, TA100, TA1535, TA1537 strains) or 0.2 ml Biotin/Tryptophan (For E.coli WP2 uvrA) and 0.5 ml of 0.2 M PBS (or 0.5 ml of cold S9 mixture) were then dispensed to each agar tube. The concentration of S9 fraction in S9 mixture used in each plate was 10%.

DURATION
- Exposure duration: 48 h

SELECTION AGENT (mutation assays): 0.2 ml Biotin/Histidine (For Salmonella typhimurium TA98, TA100, TA1535, TA1537 strains) or 0.2 ml Biotin/Tryptophan (For E.coli WP2 uvrA)

NUMBER OF REPLICATIONS: Triplicate plates were used for each of 5 concentrations of test substances, negative control and positive control respectively.



DETERMINATION OF CYTOTOXICITY : In preliminary Dose Range Finding (DRF) study, six concentrations were used to detect cytotoxicity of the test substances.

Rationale for test conditions:

No decrease of revertant colonies number, smaller colonies or thin background lawn were observed in all the concentrations of the test solution with and without S9 activation, which indicated that cytotoxic effect was not observed at a starting concentration of 5 mg / plate. Therefore, based on the preliminary study, the dose levels for test substances with and without S9 activation in the main study were selected as follows: 5.0 mg / plate, 2.5 mg / plate, 1.25 mg / plate, 0.63 mg / plate, 0.31 mg / plate, dose interval was 2.

Statistics:

Student’s t-test was used to assess whether there was any statistically significant difference between the number of revertant colonies of the test extract and its corresponding negative control.

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

Under the condition of this study, the above results show that, using water as vehicle, the test item – Dipotassium dodecenylsuccinate (aq. solution), Lot No: 170727 is non-mutagenic to the following bacteria strains: TA 1535, TA 1537, TA 98, TA 100, Escherichia coli WP2 uvrA.