Arctium lappa, ext.

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:

2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study, detailed documentation

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

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:

RCC

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Arctium lappa, ext.

EC Number:

281-658-8

EC Name:

Arctium lappa, ext.

Cas Number:

84012-13-5

IUPAC Name:

Arctium lappa, ext.

Details on test material:

- Name of test material (as cited in study report): Klettenfruchtextrakt (Sample ID: 14261)
- Physical state: honey-like, yellow liquid
- Expiration date of the lot/batch: 26-SEP-2007
- Storage condition of test material: room temperature, light protected

Method

Target gene:

TA 1537: his C 3076
TA98: his D 3052
TA1535: his G 46
WP2 uvrA: trp
TA100: his G46

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535

Details on mammalian cell type (if applicable):

Positive control substance: sodium azide, 10 µg/plate (without metabolic activation)
Positive control substance: 2-aminoanthracene, 2.5 µg/plate (with metabolic activation)

Additional strain / cell type characteristics:

other: Strain is histidine-dependent

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 100

Details on mammalian cell type (if applicable):

Positive control substance: sodium azide, 10 µg/plate (without metabolic activation)
Positive control substance: 2-aminoanthracene, 2.5 µg/plate (with metabolic activation)

Additional strain / cell type characteristics:

other: Strain is histidine-dependent

Species / strain 3

Species / strain / cell type:

S. typhimurium TA 1537

Details on mammalian cell type (if applicable):

Positive control substance: 4-nitro-o-phenylene-diamine, 50 µg/plate (without metabolic activation)
Positive control substance: 2-aminoanthracene, 2.5 µg/plate (with metabolic activation)

Additional strain / cell type characteristics:

other: Strain is histidine-dependent

Species / strain 4

Species / strain / cell type:

S. typhimurium TA 98

Details on mammalian cell type (if applicable):

Positive control substance: 4-nitro-o-phenylene-diamine, 10 µg/plate (without metabolic activation)
Positive control substance: 2-aminoanthracene, 2.5 µg/plate (with metabolic activation)

Additional strain / cell type characteristics:

other: Strain is histidine-dependent

Species / strain 5

Species / strain / cell type:

E. coli WP2 uvr A

Details on mammalian cell type (if applicable):

Positive control substance: methyl methane sulfonate, 3 µL/plate (without metabolic activation)
Positive control substance: 2-aminoanthracene, 10 µg/plate (with metabolic activation)

Additional strain / cell type characteristics:

other: Strain carries defect on genes for tryptophan biosynthesis

Metabolic activation:

with and without

Metabolic activation system:

Phenobarbital/β-Naphthoflavone induced rat liver S9, prepared from 8-12 weeks old male Wistar Hanlbm rats

Test concentrations with justification for top dose:

Pre-experiment for toxicity was performed with TA 1535, TA 1537, TA 98, TA 100 and WP2 urvA. 8 concentrations (3 - 5000 µg/plate).
Main test: 33, 100, 333, 1000, 2500, 5000 µg/plate
Test item was dissolved in DMSO on the day of experiment.

Vehicle / solvent:

- Vehicle used: DMSO
- Justification for choice of solvent/vehicle: relative non-toxicity to the bacteria

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Details on test system and experimental conditions:

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

DURATION
- Exposure duration: at least 48 hours at 37°C in the dark

Evaluation criteria:

Test item considered to be mutagen if increase in number of revertants exceeding treshold of twice (TA 98, TA 100, WP2 uvrA) or thrice (TA 1535, TA 1537) the colony count of corresponding solvent control.
A dose dependent increase is considered biologically relevant if the treshold is exceeded at more than one concentration.
An increase exceeding he treshold at only one concentration is judged as biologically relevant if reproduced in an independent second experiment.

Statistics:

Not mandatory according to Guideline

Results and discussion

Test results

Key result

Remarks on result:

other: No substantial increase in revertant colony numbers of any of the five strains was observed at any dose level, neither in presence nor absence of metabolic activation.

Remarks:

No tendency of higher mutation rates with increasing concentrations.

Any other information on results incl. tables

No substantial increase in revertant colony numbers of any of the five strains was observed at any dose level, neither in presence nor absence of metabolic activation. No tendency of higher mutation rates with increasing concentrations.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Klettenfruchtextrakt is considered to be non-mutagenic in the bacterial gene mutation test system.

Executive summary:

According to OECD 471 Klettenfruchtextrakt was dissolved in DMSO and tested with the 4 strains of Salmonella typhimurium (TA100, TA98, TA1535 and TA1537) and Escherichia coli WP2 uvr A.

Neither with nor without metabolic activation with S-9 induction of mutagenic activity was observed. Adequate positive and negative control substances were included in the test system.

Up to and including concentrations of 5000 µg/plate Klettenfruchtextrakt did not increase the mutation frequency of the 5 tested strains and is therefore considered to be non-mutagenic.