Fluorosulphuric acid

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:

July 1987

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1987

Report date:

1987

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

: only 4 strains, no strains with AT base pair at the primary reversion site, culture media used not reported

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Sodium fluoride

EC Number:

231-667-8

EC Name:

Sodium fluoride

Cas Number:

7681-49-4

Molecular formula:

NaF

IUPAC Name:

sodium fluoride

Details on test material:

- Name of test material (as cited in study report): NaF
- Molecular formula (if other than submission substance): NaF
- Molecular weight (if other than submission substance): 42 g/mol
- Physical state: solid (white powder)
- Analytical purity: 99.4%
- Purity test date: May 5, 1987
- Lot/batch No.: 26061987 (internal)
- Stability under test conditions: aqueous suspensions of NaF are stable under the experimental conditions. According to the sponsor, the compound is stable for storage for at least the test period.
- Storage condition of test material: refrigerator

Method

Species / strain

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Additional strain / cell type characteristics:

other: partly deficient in lipopolysaccharide side chains of their cell walls, UV repair ability malfunctions

Metabolic activation:

with and without

Metabolic activation system:

S9 mix

Test concentrations with justification for top dose:

first test: 0, 20, 100, 500, 2500, 12500 µg per plate
repeat test: 0, 375, 750, 1500, 3000, 6000, 12000 µg per plate

Vehicle / solvent:

the solvent used for NaF was demineralized water, and for the positive controls DMSO

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: -S9: sodium azide (only TA 1535), nitrofurantoin (only TA 100), 4-nitro-1,2-phenylenediamine (TA 1537 + TA 98), +S9: 2-aminoanthracene

Remarks:

no

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)


DURATION
- Exposure duration: 48 h




NUMBER OF REPLICATIONS:
four plates per strain and dose, both with and without S-9 mix, were used for mutant count. Four plates per strain were also used for each positive control.




DETERMINATION OF CYTOTOXICITY
- other: background growth on the plates for the mutant determination; toxic effect assumed when mutant count per plate was clearly lower than the negative control count in dose correlation; determination of titer

Evaluation criteria:

A reproducible and dose-related increase (ie. at least twice the negative control count) in mutant counts for at least one strain was considered positive.
In the case of no reproducible and dose-related increase in mutant counts in at least one strain, the result was evaluated as negative.
In the case of questionable results, the investigations continued, probably by the use of modifications, until a final evaluation was possible.

Results and discussion

Test results

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

: Doses up to and including 6000 µg per plate did not cause any bacteriotoxic effects. At higher doses, the substance had only a weak bacteriotoxic effect in TA 1535 and TA 100, so that this range could nevertheless be used for evaluation purposes.

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Remarks on result:

other: strain/cell type: S. typhimurium TA1535, TA100, TA1537, TA98

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

None of the four strains used showed a dose-related and biologically relevant increase in mutant counts over those of the negative controls. This applied both to the tests with and without S-9 mix and was confirmed by the results of the repeat tests.

 

Table 1. Summary of the results of the Ames test on NaF without S-9 mix

	TA 1535			TA 100			TA 1537			TA 98
Test/doses µg/plate	Means revertantsper plate	Titer per ml 10^8	Quotient	Means revertantsper plate	Titer per ml 10^8	Quotient	Means revertantsper plate	Titer per ml 10^8	Quotient	Means revertantsper plate	Titer per ml 10^8	Quotient
1^sttest
0	11	30.8	1.0	61	6.4	1.0	7	37.6	1.0	16	56.0	1.0
20	11	24.4	1.0	72	7.7	1.2	7	33.7	1.0	16	58.0	1.0
100	9	27.7	0.8	74	7.9	1.2	6	35.1	0.9	23	64.6	1.4
500	10	35.3	0.9	71	12.9	1.2	5	34.1	0.6	16	53.0	1.0
2500	9	35.1	0.8	67	12.6	1.1	6	35.3	0.8	19	54.3	1.2
12500	9	17.9**	0.8	69	7.2	1.1	5	32.9	0.7	17	66.8	1.0
Na-Azide	601	36.4	55.9*
NF				217	9.1	3.6*
4-NPDA							48	34.8	6.6*	93	59.6	5.7*
2-AA (+S9)		38.7			11.9			34.6			49.4
2^ndtest
0	14	48.6	1.0	64	20.9	1.0	7	50.8	1.0	17	62.0	1.0
375	15	45.7	1.1	57	11.3	0.9	6	47.8	0.9	14	65.2	0.9
750	13	49.2	0.9	62	9.9	1.0	5	39.2	0.7	19	63.9	1.1
1500	12	48.2	0.9	56	10.4	0.9	8	48.5	1.3	18	67.6	1.1
3000	16	46.1	1.1	66	10.0	1.0	8	47.6	1.2	20	69.2	1.2
6000	14	51.3	1.0	67	10.1	1.0	5	49.4	0.8	15	73.8	0.9
12000	15	26.1**	1.1	77	7.4	1.2	5	45.7	0.8	15	80.0	0.9
Na-Azide	922	49.9	67.0*
NF				257	13.2	4.0*
4-NPDA							68	57.8	10.4*	130	53.5	7.7*
2-AA (+S9)		54.8			13.3			58.1			58.3

 

Na-Azide: Sodium azide, 10 µg/plate

NF: Nitrofurantoin, 0.2 µg/plate

4-NPDA: 4-nitro-1,2-phenylenediamine, 0.5 µg/plate

2-AA: 2-aminoanthracene, 3 µg/plate

 

* = mutagenic effect

** =bacteriotoxic effect

 

 

Table 2. Summary of the results of the Ames test on NaF with S-9 mix

	TA 1535		TA 100		TA 1537		TA 98
Test/doses µg/plate	Means revertantsper plate	Quotient	Means revertantsper plate	Quotient	Means revertantsper plate	Quotient	Means revertantsper plate	Quotient
1^sttest
0	15	1.0	132	1.0	8	1.0	44	1.0
20	17	1.1	122	0.9	8	1.0	35	0.8
100	16	1.1	107	0.8	8	1.0	33	0.7
500	19	1.3	128	1.0	9	1.1	29	0.7
2500	19	1.3	85	0.6	6	0.8	45	1.0
12500	18	1.2	48**	0.4	4	0.5	35	0.8
2-AA	143	9.7*	395	3.0*	27	3.5*	373	8.6*
2^ndtest
0	23	1.0	104	1.0	9	1.0	49	1.0
375	28	1.2	105	1.0	10	1.1	43	0.9
750	25	1.1	128	1.2	11	1.3	36	0.7
1500	19	0.8	108	1.0	7	0.8	42	0.9
3000	24	1.0	133	1.3	7	0.8	53	1.1
6000	20	0.9	132	1.3	8	0.9	36	0.7
12000	20	0.8	102	1.0	6	0.7	32	0.7
2-AA	235	10.1*	540	5.2*	43	5.0*	634	13.1*

 

2-AA: 2-aminoanthracene,3 µg/plate

 

* = mutagenic effect

** =bacteriotoxic effect

 

Applicant's summary and conclusion

Conclusions:

Interpretation of results:
negative without metabolic activation
negative with metabolic activation

Executive summary:

Herbold BA (1987)

NaF (as a surrogate for fluorosulphuric acid) was investigated in a Salmonella / microsome test for point-mutagenic effects in doses up to 12500 µg per plate on four Salmonella typhimurium LT2 mutants with and without metabolic activation. Test was performed similar to the OECD guideline 471 with restrictions (Only four strains, no strains with AT base pair as primary reversion site. Different positive control substances used in comparison with OECD guideline. Culture media used: not reported).

For the test the histidine-auxotrophic strains TA 1535, TA 100, TA 1537 and TA 98 were used.

Doses up to and including 6000 µg per plate did not cause any bacteriotoxic effects. The total bacteria counts remained unchanged. No inhibition of growth was observed.

At higher doses, the substance had only a bacteriotoxic effect in TA 1535 and TA 100, so that this range could nevertheless be used for evaluation purposes. Substance precipitation occurred from the dose 500 µg per plate.

Evidence of mutagenic activity for NaF was not found with and without metabolic activation. Neither a dose-related doubling of the mutant count nor a biologically relevant increase in the same, was observed in comparison with the negative controls.

The positive controls sodium azide (Na-azide) , nitrofurantoin (NF), 4-nitro-1,2-phenylene-diamine (4-NPDA),  and 2-aminoanthracene (2 -AA) had a marked mutagenic effect, as can be seen from the biologically relevant increase in mutant colonies, compared to the corresponding negative controls.