Methanesulfonamide, 1,1,1-trifluoro-N-[(trifluoromethyl)sulfonyl]-

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:

from 30 March 2007 to 22 May 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study, OECD 471 compliant.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

02 sept 2006

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

435-300-4

EC Name:

-

Cas Number:

82113-65-3

Molecular formula:

C2HNO4F6S2

IUPAC Name:

1,1,1-trifluoro-N-trifluoromethanesulfonylmethanesulfonamide

Test material form:

other: aqueous solution

Method

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:

S9 mix from rat liver cells

Test concentrations with justification for top dose:

3; 10; 33; 100; 333; 1000; 2500; and 5000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: deionised water
- Justification for choice of solvent/vehicle: usually recommended by the guideline.

Controls

Untreated negative controls:

yes

Remarks:

solvent served as negative controls

Negative solvent / vehicle controls:

yes

Remarks:

Deionised water

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

methylmethanesulfonate

other: 2-aminoanthracene; 4-nitro-o-phenylene-diamine

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation) and pre-incubation method.

DURATION
- Preincubation period: In the pre-incubation assay 100 µL test solution, 500 µL S9 mix / S9 mix substitution buffer and 100 µL bacterial suspension were mixed in a test tube and shaken at 37°C for 60 minutes. After pre-incubation 2.0 ml overlay agar (45° C) was added to each tube. The mixture was poured on selective agar plates.
- Exposure duration: 48 hours

NUMBER OF REPLICATES: 3

NUMBER OF CELLS EVALUATED: The colonies were counted using the Petri Viewer Mk2 (Perceptive Instruments Ltd, Suffolk CB 7BN, UK) with the software program Ames Study Manager. The counter was connected to an IBM AT compatible PC with printer to print out the individual values and the means from the plates for each concentration together with standard deviations and enhancement factors as compared to the spontaneous reversion rates.

POSITIVE CONTROLS:
Without metabolic activation
Strains: TA 1535, TA 100
Name: sodium azide, NaN3
Concentration: 10 µg/plate

Strains: TA 1537, TA 98
Name: 4-nitro-o-phenylene-diamine, 4-NOPD
Concentration: 1 0 IJg/plate in TA 98, 50 IJg/plate in TA 1537

Strain: WP2 uvrA
Name: methyl methane sultanate, MMS
Concentration: 3 µL/plate

With metabolic activation
Strains: TA1535, TA 1537, TA 98, TA 100, WP2 uvrA
Name: 2-aminoanthracene, 2-AA
Concentration: 2.5 µg/plate {TA 1535, TA 1537, TA 98, TA 100), 1 0 µg/plate (WP2 uvrA)

Evaluation criteria:

A test item is considered as a mutagen if a biologically relevant increase in the number of revertants exceeding the threshold of twice (strains TA 98, TA 100, and WP2 uvrA) or thrice (strains TA 1535 and TA 1537) the colony count of the corresponding solvent control is observed (3).
A dose dependent increase is considered biologically relevant if the threshold is exceeded at more than one concentration (2).
An increase exceeding the threshold at only one concentration is judged as biologically relevant if reproduced in an independent second experiment.
A dose dependent increase in the number of revertant colonies below the threshold is regarded as an indication of a mutagenic potential if reproduced in an independent second experiment. However, whenever the colony counts remain within the historical range of negative and solvent controls such an increase is not considered biologically relevant.

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:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

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

Results for plate incorporation (mean of 3 replicates):

	TA 98		TA 100		TA 1535		TA 1537		WP2 uvrA
Conc.	without S9 mix	with S9 mix	without S9 mix	with S9 mix	without S9 mix	with S9 mix	without S9 mix	with S9 mix	without S9 mix	with S9 mix
µg/plate
0	36,3	42,7	105,3	111	18,3	19	14	17,3	32,3	46
3	41,7	52	118	101,3	15	19	12,7	15,7	33,7	42,7
10	36,7	43,7	109	96,7	13,7	18	10,3	15	43	44
33	33,3	38	108	101,3	15	16,7	12,3	16,7	35,3	38,7
100	38	43,3	116,7	108	22,7	17	11,7	14,3	35,3	38
333	43	45,7	118	89	17,3	22,7	10,3	14	32,3	42,7
1000	34,7	41	99,3	93,3	13,3	17	10	15,7	31,3	44,3
2500	36,7	42,7	105,7	107,3	12,3	17,3	8,7	16	37	40,7
5000	34,7	46,7	108,3	110	12,3	21	12,7	16,7	28,7	46,7
Untreated controls	41,3	40	149	111	12,7	20	14	20,3	37,3	46,3
Positive control	527	1008,7	1924,3	725,3	1862	190,3	89	178,3	632,7	248,3

Results with pre-incubation method (mean of 3 replicates):

	TA 98		TA 100		TA 1535		TA 1537		WP2 uvrA
Conc.	without S9 mix	with S9 mix	without S9 mix	with S9 mix	without S9 mix	with S9 mix	without S9 mix	with S9 mix	without S9 mix	with S9 mix
µg/plate
0	37	44,7	131	126,3	18,3	18	11,3	15	38,7	43,3
3	33,7	49,7	112,3	111	14,3	17,3	12	16,7	39,3	51
10	40	47	135,3	125,3	13,3	19,3	13	14,7	43,3	44,7
33	36,7	50,3	139	149	15,3	19,7	13	15,7	40,3	45,7
100	41,3	44,3	137	135,7	15	15,3	9,3	13,7	33,7	45,7
333	34,7	54,3	135,3	123,7	15,3	19,7	11,3	18,3	41,3	51,3
1000	38,7	48,3	143,3	135,3	10,3	20,7	13	14,3	26	51
2500	43,3	49	131,7	130,3	15,7	15,7	10,7	13,7	27,3	54
5000	34,3	45,3	139,7	137,7	8	16,7	10,3	15,3	31,7	44,7
Untreated controls	39,7	53,3	120,7	126	17,7	15,3	10,3	16,3	37	48,7
Positive control	549	922,3	2344	1105,3	2064	278,3	115,7	121,3	456,3	322,7

Applicant's summary and conclusion

Conclusions:

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

The test item did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used.

Executive summary:

The test item TFSIH was assessed for its potential to induce gene mutations in the plate incorporation test (experiment I) and the pre-incubation test (experiment 11) using Salmonella typhimurium strains TA 1535, TA 1537, TA 98, and TA 100, and the Escherichia coli strain WP2 uvrA. The assay was performed in two independent experiments both with and without liver microsomal activation. Each concentration and the controls were tested in triplicate. The test item was tested at the following concentrations (active ingredient): 3; 10; 33; 100; 333; 1000; 2500; and 5000 µg/plate.

The plates incubated with the test item showed normal background growth up to 5000 µg/plate with and without S9 mix in both experiments. No toxic effects, evident as a reduction in the number of revertants, occurred in the test groups with and without metabolic activation. No substantial increase in revertant colony numbers of any of the five tester strains was observed following treatment with TFSIH at any dose level, neither in the presence nor absence of metabolic activation (S9 mix). There was also no tendency of higher mutation rates with increasing concentrations in the range below the generally acknowledged border of biological relevance. Appropriate reference mutagens were used as positive controls. They showed a distinct increase of induced revertant colonies. In conclusion, it can be stated that during the described mutagenicity test and under the experimental conditions reported, the test item did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used.