Potassium N,N-dimethylglycinate

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:

2015-04-15 to 2015-04-24

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline compliant study report.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

(1997)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Version / remarks:

(2008)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.5100 - Bacterial Reverse Mutation Test (August 1998)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

BASF SE Experimental Toxicology and Ecology, 67056 Ludwigshafen, Germany

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Potassium N,N-dimethylglycinate

EC Number:

241-629-2

EC Name:

Potassium N,N-dimethylglycinate

Cas Number:

17647-86-8

Molecular formula:

C4H8NO2.K

IUPAC Name:

potassium 2-(dimethylamino)acetate

Details on test material:

- Name of test material (as cited in study report): Potassium N,N-dimethylglycinate
- Substance type: organic salt
- Physical state: solid
- Analytical purity: 94 %
- Storage condition of test material: at room temperature; substance is highly hygroscopic

Method

Species / strain

Species / strain / cell type:

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

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

S9 mix (phenobarbital and β-naphthoflavone induced rat liver)

Test concentrations with justification for top dose:

1st experiment: 0; 33; 100; 333; 1000; 2650 and 5300 μg/plate with and without S9 mix (SPT)
2nd experiment: 0; 33; 100; 333; 1000; 2650 and 5300 μg/plate with and without S9 mix (PIT)

Vehicle / solvent:

- Vehicle used: water
- Justification for choice of solvent/vehicle: due to good solubility of the test substance.

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Remarks:

2-AA

Positive control substance:

other: 2-aminoanthracene

Remarks:

with S9 mix (TA 1535, TA 100, TA 1537, TA 98, E. coli WP2 uvrA)

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Remarks:

MNNG

Positive control substance:

other: N-methyl-N'-nitro-N-nitrosoguanidine

Remarks:

without S9 mix (TA 1535, TA 100)

Controls 3

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Remarks:

NOPD

Positive control substance:

other: 4-nitro-o-phenylenediamine

Remarks:

without S9 mix (TA 98)

Controls 4

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Remarks:

AAC

Positive control substance:

9-aminoacridine

Remarks:

without S9 mix (TA 1537)

Controls 5

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Remarks:

4-NQO

Positive control substance:

4-nitroquinoline-N-oxide

Remarks:

without S9 mix (E. coli WP2 uvrA)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation); preincubation

DURATION
- Preincubation period: 20 min
- Exposure duration: 48 to 72 hours

NUMBER OF REPLICATIONS: 3

DETERMINATION OF CYTOTOXICITY
- Method: relative total growth and clearing of background lawn

Evaluation criteria:

The test substance was considered positive in this assay if the following criteria were met:
- A dose-related and reproducible increase in the number of revertant colonies, i.e. at least doubling (bacteria strains with high spontaneous mutation rate, like TA 98, TA 100 and E.coli WP2 uvrA) or tripling (bacteria strains with low spontaneous mutation rate, like TA 1535 and TA 1537) of the spontaneous mutation rate in at least one tester strain either without S9 mix or after adding a metabolizing system.
A test substance was generally considered non-mutagenic in this test if:
- The number of revertants for all tester strains were within the historical negative control data range under all experimental conditions in at least two experiments carried out independently of each other.

Results and discussion

Test results

Species / strain:

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

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Please refer to "Additional information on results"

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
No test specific confounding factors were observed during the test.

COMPARISON WITH HISTORICAL CONTROL DATA:
The positive control substances both with and without S9 mix induced a distinct increase in the number of revertant colonies within the range of the historical positive control data or above.

ADDITIONAL INFORMATION ON CYTOTOXICITY:
No bacteriotoxic effect (reduced his- or trp- background growth, decrease in the number of his+ or trp+ revertants) was occasionally observed in the standard plate test. In the preincubation assay bacteriotoxicity (reduced his- or trp- background growth, decrease in the number of his+ or trp+ revertants) was occasionally observed depending on the strain and test conditions at 5300 μg/plate.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1: Results

Experiment 1 (SPT)
Dose (µg/plate)	Mean number of revertant colonies/3 replicate plates with different strains of Salmonella typhimurium and E. coli
	TA1535	TA1537	TA98	TA100	WP2 uvrA
	Results with S9
Spontaneous Reversion	12.3	7.3	26.7	94.7	21.3
Positive control	286.7	175.3	2167	2271	169
33	13	10.7	25.7	108	20.7
100	14	10.7	26	125.3	20
333	11.3	8	22.3	122.3	18.3
1000	14.7	7.3	24	104.3	26.3
2650	16	10.3	27.7	118.3	16.7
5300	16.3	6.3	19.7	106	27
	Results without S9
Spontaneous Reversion	16.7	8	19.7	109.3	24.7
Positive control	4892.3	1175.7	732.7	3674.7	1334
33	15.7	8.7	18.7	100.7	22.7
100	13.3	9	17	99.3	18.3
333	17.3	8.7	21.3	99.3	17.7
1000	15.7	8.7	25.7	90.7	18.3
2650	16	6.7	18.3	100.3	24
5300	23	9.3	16.3	110.7	18.3
Experiment 2 (PIT)
Dose (µg/plate)	Mean number of revertant colonies/3 replicate plates with different strains of Salmonella typhimurium and E. coli
	TA1535	TA1537	TA98	TA100	WP2 uvrA
	Results with S9
Spontaneous Reversion	8	7.3	26.7	101.7	24.7
Positive control	248.3	176.3	2048.3	2127.7	63
33	8	7.7	28.7	93.3	26.7
100	9.7	6.7	27.7	107	24
333	7	6.7	22.7	104	26
1000	7.7	6.3	23.3	89.7	23.7
2650	9	8.7	22.7	96	31.3
5300	9.3	4.3	19.3	93.7	23.3
	Results without S9
Spontaneous Reversion	11.7	6.3	15.7	102	24
Positive control	3956.3	635.3	356	2458.3	294.3
33	10.3	6	17	102.7	26.7
100	11.7	6.3	18.7	104.3	21
333	11.3	5.3	19.3	94.7	23.3
1000	9.3	4	13.7	87.7	23.7
2650	11.7	5.7	18	69	19
5300	2.7	0	0	67.7	2.7