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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in mammalian cells
Remarks:
Type of genotoxicity: gene mutation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
November 1992 - April 1993
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: GLP study from 1993, some deviations from current updated guidelines.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1993
Report Date:
1993

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)
Deviations:
yes
Remarks:
deviations according to updated guideline, such as number of cells; no purity indicated
GLP compliance:
yes
Type of assay:
mammalian cell gene mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Dianol 320
- Physical state: multiple-sized white lumps
- Analytical purity: not indicated

Method

Target gene:
HGPRT locus
Species / strain
Species / strain / cell type:
Chinese hamster lung fibroblasts (V79)
Metabolic activation:
with and without
Metabolic activation system:
S9-mix
Test concentrations with justification for top dose:
first assay: -S9: 0, 10, 25, 50, 75, 100, 150 µg/mL; +S9: 0, 10, 20, 40, 80, 100 µg/mL
second assay: -S9: 0, 25, 50, 75, 100, 125 µg/mL; +S9: 0, 25, 50, 75, 100, 125, 150 µg/mL
supplementary assay: -S9: 0, 130, 140, 150 µg/mL; +S9: 0, 160, 180, 200 µg/mL
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: DMSO
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
Positive controls:
yes
Positive control substance:
ethylmethanesulphonate
Remarks:
Migrated to IUCLID6: 7,12-dimethylbenzanthracene (DMBA)
Details on test system and experimental conditions:
DURATION
- Preincubation period: 24h
- Exposure duration: 3h
- Expression time (cells in growth medium): 7 days

NUMBER OF REPLICATIONS: 2

NUMBER OF CELLS EVALUATED: 100 cells/plate, 3 plates

DETERMINATION OF CYTOTOXICITY
- Method: cloning efficiency
Evaluation criteria:
Mutant frequency per 10E5 survivors = (no. of cells plated for PE/mean no. of PE colonies) x mean no. of 6-TG-r colonies. A comparison is made between the mutation frequency of the treated plaets and control plates. Statistical analysis is not applied.
The study is considered valid if:
solvent control data are acceptable and if positive control data are acceptable.
The test is considered positive if increases in mutation frequencies and/or mutatant colony numbers are consistently observed in each if the two assays. The significant elevantion of mutation frequency at only one concentration or in isolated single cultures at more than one concentration will be analysed on a case-by-case basis.
Statistics:
Statistical analysis is not applied.

Results and discussion

Test results
Key result
Species / strain:
Chinese hamster lung fibroblasts (V79)
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
from 130 µg/mL onwards -S9, from 160 µg/mL onwards +S9
Vehicle controls validity:
valid
Positive controls validity:
valid
Additional information on results:
TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: cloudiness was obserbed at 200 µg/mL


RANGE-FINDING/SCREENING STUDIES: included

Any other information on results incl. tables

In the first mutation assay no cytotoxicity was apparent at concentrations up to and including 100 µg/mL; total cell death was observed at 150 µg/mL (-S9). In the second test, no cytotoxicity was observed up to and including 150 µg/mL. In the supplementary assay, reduced plating efficiency was observed at and above 130 µg/mL (-S9); in the presense of S9 toxicity was observed at and above 160 µg/mL.

No increases in mutation frequencies (or mutant colony numbers) were observed in Dianol 320 treated culteres, both in the absence and presence of S9.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative

Under the test conditions, 4,4’-Isopropylidenediphenol, propoxylated (BPA+2PO) did not show mutagenic activity at the HGPRT gene locus, both in the absence and in the presence of metabolic activating system.
Executive summary:

4,4’-Isopropylidenediphenol, propoxylated (BPA+2PO) was examined for mutagenic potential by measuring its ability to induce mutation in Chinese hamster (V79) cells at the hypoxanthine-guanine-phosphoribosyl transferase (HGPRT) locus. Under the experimental conditions of the test, 4,4’-Isopropylidenediphenol, propoxylated (BPA+2PO) showed no evidence of mutagenic activity at the HGPRT gene locus, when cells were treated in the absence or presence of S-9 mix. The sensibility of the assay system was proven by the observed responses to known mutagens.