L-Ascorbic acid, 2-(dihydrogen phosphate), sodium salt (1:3)

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 1997-07-03 to 1997-07-24

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

May 1983, revised Draft 1996

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 472 (Genetic Toxicology: Escherichia coli, Reverse Mutation Assay)

Version / remarks:

May 1983, revised Draft 1996

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

92/69/EEC

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

425-180-1

EC Name:

-

Cas Number:

66170-10-3

Molecular formula:

C6H6O9P.3Na

IUPAC Name:

trisodium (2R)-2-[(1S)-1,2-dihydroxyethyl]-5-oxo-4-(phosphonatooxy)-2,5-dihydrofuran-3-olate

Details on test material:

- Name of test material (as cited in study report): Sodium ascorbyl phosphate
- Physical state: Beige powder
- Analytical purity: 85.4%
- Date of manufacture: 1997-05-02
- Lot/batch No.: 28600/37-9
- Storage condition of test material: Room temperature

Method

Target gene:

The rate of induced back mutations of several bacteria mutants from histidine auxotrophy (his-) to histidine prototrophy (his+) is determined.

Escherichia coli WP2 uvrA which has an AT base pair at the primary reversion site is a derivative of E. coli WP2 with a deficient excision repair and is used to detect substances which induce base pair substitutions. The rate of induced back mutations from tryptophan auxotrophy (trp-) to tryptophan independence (trp+) is determined.

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 100

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

S9 fraction

Test concentrations with justification for top dose:

0; 24; 120; 600; 3,000 and 6,000 µ/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: water
- Justification for choice of solvent/vehicle: Due to the good solubility of the test substance in water, water was selected as the vehicle.

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Remarks:

for TA 135, TA 100, TA 1537, TA 98 with S-9 mix

Positive control substance:

other: 2-aminoanthracene

Controls 2

Positive controls:

yes

Remarks:

for TA 1535, TA 100 and E.coli WP2 uvrA without S9-mix

Positive control substance:

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

Controls 3

Positive controls:

yes

Remarks:

for TA 98 without S9-mix

Positive control substance:

other: 4-nitro-o-phenylendiamine

Controls 4

Positive controls:

yes

Remarks:

for TA 1537 without S9-mix

Positive control substance:

9-aminoacridine

Controls 5

Positive controls:

yes

Remarks:

for E.coli WP2 uvrA without S9-mix

Positive control substance:

N-ethyl-N-nitro-N-nitrosoguanidine

Details on test system and experimental conditions:

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

DURATION
- Preincubation period: 20 min
- Exposure duration: 48-72 hrs

NUMBER OF REPLICATIONS:
3

DETERMINATION OF CYTOTOXICITY
Method
- decrease in the number of revertants
- clearing or diminution of the background lawn (= reduced his- or trp- background growth)
- reduction in the titer

Evaluation criteria:

The test chemical is considered positive in this assay if the following criteria are met:
- A dose-related and reproducible increase in the number of revertant colonies, i.e. about doubling of the spontaneous mutation rate in at least one tester strain either without S-9 mix or after adding a metabolizing system.
A test substance is generally considered nonmutagenic in this test if:
The number of revertants for all tester strains were within the historical negative control range under all experimental conditions in two experiments carried out independently of each other.

Statistics:

Determination of Mean and standard deviation

Results and discussion

Test results

Test results 1

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:

A slight decrease in the number of revertants was occasionally observed depending an the strain and test conditions from about 3,000 µg/plate onward.

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

A slight decrease in the number of revertants was occasionally observed depending an the strain and test conditions from about 3,000 µg/plate onward.

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'. Remarks: S. typh. TA1535,TA1537, TA98, TA100, E.coli WP2uvrA

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Sodium ascorbyl phosphate is not mutagenic.