Reaction products of fatty acids, C18 (unsaturated) alkyl with sulfur trioxide, potassium salts

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in mammalian cells

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

May-July 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline conformant study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)

GLP compliance:

yes (incl. QA statement)

Type of assay:

mammalian cell gene mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Reaction products of fatty acids, C18 (unsaturated) alkyl with sulfur trioxide, potassium salts

EC Number:

701-179-4

Molecular formula:

(C18H33)nO7K2S, n= 1-2

IUPAC Name:

Reaction products of fatty acids, C18 (unsaturated) alkyl with sulfur trioxide, potassium salts

Specific details on test material used for the study:

Name of test substance: Octadecanoic acid, sulfo-, potassium salt
CAS No.: 67968-63-2
Test substance No.: 14/0449-1
Batch identification: 0012127444
Purity: 51.92% (project No. 14L00285)
Homogeneity: given (visually)
Date of production: 23 Jun 2014
Storage conditions: room temperature

Method

Target gene:

hypoxanthine-guanine phosphoribosyl transferase (HGPRT)

Species / strain

Species / strain / cell type:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Metabolic activation system:

rat liver S9 mix induced by phnobarbital i.p. and b-naphthoflavone orally

Test concentrations with justification for top dose:

1st experiment with and without S9 mix: 10.9 (only with S9), 21.9, 43.8, 87.5, 175.0, 350.0, 700.0 (only without S9) ug/mL
2nd experiment with and without S9 mix: 12.5 (only with S9), 25.0, 50.0, 100.0, 200.0, 400.0, 800.0 (only without S9) ug/mL

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: Ham´s F12
- Justification for choice of solvent/vehicle: Due to the good solubility of the test substance in water, the aqueous culture medium (Ham's
F12) was selected as vehicle, which has been demonstrated to be suitable in the CHO/HPRT assay and for which historical control data are available.

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Remarks:

without metabolic activation: EMS; with metabolic activation: DMBA

Positive control substance:

7,12-dimethylbenzanthracene

ethylmethanesulphonate

Evaluation criteria:

relative and absolute cloning efficiency, mutant frequency

Results and discussion

Test results

Species / strain:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

1st experiment (without S9 mix):

Test groups (ug/mL)	Mutant frequency (per 10^6cells)
	Uncorrected	Corrected
Vehicle control	2.50	3.16
21.9	n.c.
43.8	0.28	0.30
87.5	5.00	5.66
175.0	1.11	1.33
350.0	1.39	1.82
700.0	n.c.
EMS	85.56	119.59

 

1st experiment (with S9 mix):

Test groups (ug/mL)	Mutant frequency (per 10^6cells)
	Uncorrected	Corrected
Vehicle control	0.28	0.30
10.9	n.c.
21.9	1.11	1.40
43.8	2.50	3.15
87.5	0.28	0.36
175.0	0.00	0.00
350.0	n.c.
DMBA	203.89	334.53

 

2nd experiment (without S9 mix):

Test groups (ug/mL)	Mutant frequency (per 10^6cells)
	Uncorrected	Corrected
Vehicle control	5.28	5.97
25	2.50 2.76
50	3.89	4.75
100	4.72	5.81
200	1.67	2.32
400	nc	nc
EMS	82.22	102.64

 

2nd experiment (with S9 mix):

Test groups (ug/mL)	Mutant frequency (per 10^6cells)
	Uncorrected	Corrected
Vehicle control	3.33	3.49
12.5	n.c.
25	0.28	0.29
50	3.33	4.00
100	2.50	3.04
200	0.56	0.64
DMBA	86.39	107.87

 

n.c. = culture was not continued since a minimum of only four analyzable concentrations is required

Applicant's summary and conclusion

Conclusions:

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

The substance Octadecanoic acid, sulfo-, potassium salt was assessed for its potential to induce gene mutations at the hypoxanthine-guanine phosphoribosyl transferase (HPRT) locus in Chinese hamster ovary (CHO) cells in vitro. Two independent experiments were carried out, both with and without the addition of liver S9 mix from phenobarbital- and β-naphthoflavone induced rats (exogenous metabolic activation).

Based on the results of the present study, the test substance did not cause any dosedependent increase in the mutant frequencies both without S9 mix and after the addition of a metabolizing system in two experiments performed independently of each other. Thus, under the experimental conditions of this study, the test substance Octadecanoic acid, sulfo-, potassium salt is not mutagenic in the HPRT locus assay under in vitro conditions in CHO cells in the absence and the presence of metabolic activation.