Registration Dossier

Toxicological information

Genetic toxicity: in vitro

Currently viewing:

Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Remarks:
Type of genotoxicity: gene mutation
Type of information:
migrated information: read-across based on grouping of substances (category approach)
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
GLP guideline study tested with the source substance D-Glucopyranose, oligomers, hexyl glycosides. According to the ECHA guidance document “Practical guide 6: How to report read-across and categories (March 2010)”, the reliability was changed from RL1 to RL2 to reflect the fact that this study was conducted on a read-across substance.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1998
Report Date:
1998

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPP 84-2
Deviations:
no
Qualifier:
according to
Guideline:
JAPAN: Guidelines for Screening Mutagenicity Testing Of Chemicals
Deviations:
no
GLP compliance:
yes (incl. certificate)
Remarks:
THE DEPARTEMENT OF HEALTH OF THE GOVERNMENT OF THE UNITED KINGDOM
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in the study report): trade name
- Physical state: amber viscous liquid
- Analytical purity: 75%
- Lot/Batch number: P8030
- Storage conditions: room temperature in the dark

Method

Target gene:
his operon (S. typhimurium) and trp operon (E. coli)
Species / strain
Species / strain / cell type:
other: S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2uvrA
Details on mammalian cell type (if applicable):
- Type and identity of media: nutrient broth (Oxoid Limited)
- Properly maintained: yes
- Periodically checked for karyotype stability: yes
- Periodically "cleansed" against high spontaneous background: yes
Metabolic activation:
with and without
Metabolic activation system:
co-factor supplemented post-mitochondrial fraction (S9-mix), prepared from the livers of male Sprague Dawley rats induced with Aroclor 1254 (single i.p. injection of 500 mg/kg bw)
Test concentrations with justification for top dose:
Range finding study: 0, 0.1 5, 0.5, 1.5, 5, 15, 50, 150, 500, 1500 and 5000 µg/plate
Main study (Experiment I and II): 0, 50, 150, 500, 1500 and 5000 µg/plate
Vehicle / solvent:
- Vehicle/solvent used: DMSO
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
Remarks:
DMSO
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: ENNG (-S9; 2-5 µg/plate; TA100, TA1535, WP2 uvrA); 9-AA (-S9; 80 µg/plate; TA1537); 4-NQO (-S9; 0.2 µg/plate; TA 98); 2-AA (+S9; 1-10 µg/plate; TA 100, TA 1535, TA 1537, WP2 uvrA); BP (+S9; 5 µg/plate; TA 98)
Remarks:
N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG); 9-Aminoacridine (9AA); 4-Nitroquinoline-1-oxide (4NQO); 2 -Aminoanthracene (2AA); Benzo(a)pyrene (BP)
Details on test system and experimental conditions:
METHOD OF APPLICATION: plate incorporation

DURATION
- Exposure duration: 48 h

NUMBER OF REPLICATIONS: triplicate

NUMBER OF CELLS EVALUATED: not applicable; total frequency of revertant colonies assessed

DETERMINATION OF CYTOTOXICITY
- Method: relative total growth, reduction of the bacterial background lawn, other: frequency of revertant colonies assessed using a Domino colony counter
Evaluation criteria:
The test material was considered to be positive in this test system if the following criteria were met:
- the test was valid (see criteria below)
- test material induced a reproducible, dose-related and statistically (Dunnett's method of linear regression) significant increase in the revertant count in at least one strain of bacteria.
- a greater than 2-fold increase in revertant count was observed in two experiments.

Acceptance Criteria: the reverse mutation assay was considered valid if the following criteria were met:
- all tester strain cultures exhibited a characteristic number of spontaneous revertants per plate in the vehicle and untreated controls which was within the historical control range
- the appropriate characteristics for each tester strain were confirmed, e.g. rfa cell-wall mutation and pkM101 plasmid R-factor etc.
- all tester strain cultures were in the range of 1 to 9.9 x 10E+9 bacteria per mL
- each mean positive control value was at least two times the respective vehicle control value for each strain, thus demonstrating both the intrinsic sensitivity of the tester strains to mutagenic exposure and the integrity of the S9-mix.
- a minimum of 4 non-toxic dose levels was achieved and
- no evidence of excessive contamination was observed.
Statistics:
Mean values and standard deviation were calculated for the number of revertants of each group. Statistical analysis was performed using the Dunnett's method of linear regression.

Results and discussion

Test results
Species / strain:
other: S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2uvrA
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
Additional information on results:
RANGE-FINDING/SCREENING STUDIES:
The dose range of the test material used in the preliminary toxicity study was 0, 0.1 5, 0.5, 1.5, 5, 15, 50, 150, 500, 1500 and 5000 µg/plate. The test
material was non-toxic to the strains of bacteria used (TA100 and WP2uvrA).

COMPARISON WITH HISTORICAL CONTROL DATA:
Vehicle and positive control values were within historical control values.
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1. Maximum number of revertants (Mean ± SD)

Plate incorporation assay (Experiment I: 0, 50, 150, 500, 1500 and 5000 µg/plate)

 

-S9

+S9

Strain

Control

(DMSO)

Test compound (µg/plate)

Positive controls

Control

(DMSO)

Test compound (µg/plate)

Positive controls

TA 100

108 ± 8

116 ± 2 (5000)

785 ± 40

120 ± 7

133 ± 6 (150)

1117 ± 113

TA 1535

35 ± 2

34 ± 3 (5000)

247 ± 34

18 ± 6

24 ± 3 (1500)

258 ± 2

WP2 uvrA

28 ± 2

29 ± 2 (150)

781 ± 39

36 ± 5

32 ± 3 (150)

1203 ± 17

TA 98

38 ± 6

40 ± 4 (50)

130 ± 15

50 ± 4

51 ± 4 (1500)

540 ± 186

TA 1537

6 ± 2

9 ± 2 (1500)

1112 ± 98

13 ± 3

14 ± 1 (150)

286 ± 40

Plate incorporation assay (Experiment II: 0, 50, 150, 500, 1500 and 5000 µg/plate)

 

-S9

+S9

Strain

Control

(DMSO)

Test compound (µg/plate)

Positive controls

Control

(DMSO)

Test compound (µg/plate)

Positive controls

TA 100

142 ± 5

151 ± 8 (500)

530 ± 42

136 ± 13

148 ± 4 (5000)

986 ± 117

TA 1535

27 ± 2

30 ± 4 (150)

288 ± 49

22 ± 6

26 ± 4 (1500)

285 ± 52

WP2 uvrA

21 ± 6

27 ± 1 (5000)

751 ± 31

21 ± 5

22 ± 4 (500)

942 ± 64

TA 98

36 ± 6

38 ± 2 (150)

122 ± 7

41 ± 2

43 ± 4 (50)

606 ± 15

TA 1537

10 ± 2

12 ± 3 (1500)

938 ± 152

16 ± 1

17 ± 1 (150)

402 ± 21

                                                                                 

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative