Cyclooctapentylose

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in mammalian cells

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:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)

Deviations:

no

GLP compliance:

yes

Type of assay:

mammalian cell gene mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Cycloheptapentylose

EC Number:

231-493-2

EC Name:

Cycloheptapentylose

Cas Number:

7585-39-9

Molecular formula:

C42H70O35

IUPAC Name:

5,10,15,20,25,30,35-heptakis(hydroxymethyl)-2,4,7,9,12,14,17,19,22,24,27,29,32,34-tetradecaoxaoctacyclo[31.2.2.2~3,6~.2~8,11~.2~13,16~.2~18,21~.2~23,26~.2~28,31~]nonatetracontane-36,37,38,39,40,41,42,43,44,45,46,47,48,49-tetradecol (non-preferred name)

Details on test material:

BETA-CYCLOOEXTRIN
BATCH 0152
Beta cyclodextrin % dry basis 100
Reducing power, as glucose % < 0. 1
Protein residue (N 6.25) mg/kg < 50
Residue on ignition % < 0. 1
Heavy metals mg/kg < 5
Trichloroethylene mg/kg < 0.1

Method

Target gene:

HPRT locus

Species / strain

Species / strain / cell type:

Chinese hamster lung fibroblasts (V79)

Details on mammalian cell type (if applicable):

- Type and identity of media:
- Properly maintained: yes

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

S9

Test concentrations with justification for top dose:

TOXICITY TEST
-Treatment time
With S9 mix: 3 hours
Without S9 mix: 3 hours
- Doses studied (µg/ml)
With S9 mix: 10 - 30 -100 - 300 - 1000
Without S9 mix: 10 - 30 -100 - 300 - 1000

MUTAGENICITY TEST
-Treatment time:
With S9 mix: 3 hours
Without S9 mix: 3 hours
- Doses studied (µg/ml)
With S9 mix: 30 -100 - 300 - 1000
Without S9 mix: 30 -100 - 300 - 1000

Vehicle / solvent:

H21 DMEM medium culture
Dulbecco H21 (Gibco) medium containing 7.5 % of foetal calf serum, glutamine (1 % of a 3 % solution) and antibiotics (Penicillin, Streptomycin,
Fungizone)

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

benzo(a)pyrene

Remarks:

with S9

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

methylmethanesulfonate

Remarks:

without S9

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium;

DURATION
- Exposure duration: 3 hr
-Expression time: T7
- Selection time (if incubation with a selection agent): 3 hr
- Fixation time (start of exposure up to fixation or harvest of cells):


SELECTION AGENT (mutation assays): 6-thioguanine (5 µg/Iml)
STAIN (for cytogenetic assays): Giemsa


NUMBER OF REPLICATIONS: 2


NUMBER OF CELLS EVALUATED:


DETERMINATION OF CYTOTOXICITY
- Method: mitotic index

Evaluation criteria:

A study is accepted if :
-the survival rate of the solvent control is 50 % higher than the number of the cells replated at TO and T7,
- the spontaneous mutation frequency of the negative control is tower than 2 x 10-5
- the mutation frequency of the positive control· is significantly increased compared with the solvent (higher 10 folds for EMS and higher 5 folds for B[a]P). The observed values must be close to those of historical positive controls.

Statistics:

not reported

Results and discussion

Test results

Species / strain:

Chinese hamster lung fibroblasts (V79)

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:

TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: not reported
- Effects of osmolality: not reported
- Evaporation from medium: not reported
- Water solubility: not reported
- Precipitation: not reported
- Other confounding effects: not reported


RANGE-FINDING/SCREENING STUDIES: yes


COMPARISON WITH HISTORICAL CONTROL DATA: yes

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Substance did not induce gene mutations in the HPRT-test

Executive summary:

For this endpoint the read-across approach based on grouping of substances (category approach) was used.

A study equivalent to OECD 476 was performed to investigate the potential of the read-across substance .beta.-Cyclodextrin to induce gene mutations at the HPRT locus in V79 cells of the Chinese hamster. The assay was performed in two independent experiments, using two parallel cultures each. Both main experiments were performed with and without liver microsomal activation (S9) and a treatment period of 3 hours.The highest concentration of the test item was 1000 µg/mL. The tested concentrations were 30 -100 -300 and 1000µg/mL for both experiments with and without metabolic activation. No substantial and reproducible dose dependent increase of the mutation frequency was observed in both main experiments. Appropriate reference mutagens, used as positive controls, induced a distinct increase in mutant colonies and thus, showed the sensitivity of the test item and the activity of the metabolic activation system. In conclusion it can be stated that under the experimental conditions reported the test item did not induce gene mutations at the HPRT locus in V79 cells.Therefore, .beta.-Cyclodextrin is considered to be non-mutagenic in the HPRT assay.