(phenylethyl)benzene

Genetic toxicity: in vitro

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

Study period:

26Feb 1990 - 16Mar 1990

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

This study has been performed according to OECD and/or EC guidelines and according to GLP principles. Deviation: Only Salmonella typhimurium strains were tested, no E coli-strain was included. In repeat experiment only 3 instead of 5 analysable concentrations were tested.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

No E.coli-strain was included. In repeat experiment only 3 instead of 5 analysable concentrations were tested.

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

Annex V of EEC Commission Directive 84/449/EEC

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Nisseki-SAS-40

IUPAC Name:

Nisseki-SAS-40

Details on test material:

- Substance: colourless liquid
- Batch number: 3-2
- Storage conditions: in the dark
- Purity: not reported in this report

Method

Target gene:

Histidine gene

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Additional strain / cell type characteristics:

other: uvrB and rfa deficient

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 1538

Additional strain / cell type characteristics:

other: uvrB and rfa deficient

Metabolic activation:

with and without

Metabolic activation system:

S9-mix (Aroclor 1254 induced)

Test concentrations with justification for top dose:

Preliminary test:
0; 312.5; 625; 1250; 2500; 5000 µg/ plate
Main study:
0; 8; 40; 200; 1000; 5000 µg/ plate (experiment 1)
0; 312.5; 625; 1250; 2500; 5000 µg/ plate (experiment 2)

Vehicle / solvent:

- DMSO
- Justification for choice of solvent/vehicle: DMSO control plates gave counts of revertant colonies within the normal range.

Controls

Controls 1

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

other: N-Methyl-N'-nitro-N-nitrosoguanidine at 2 µg/ plate for TA1535 and TA100; 9-Aminoacridine at 50 µg/ plate for TA1537; 4-Nitro-O-phenylenediamine at 10 µg/ plate for TA1538 and TA98

Remarks:

without S9

Controls 2

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

other: 2-Aminoanthracene at 2.5µg/ plate

Remarks:

with S9

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation);

CYTOTOXICITY: Growth of background lawn

NUMBER OF REPLICATIONS: 2 (preliminary) or 3 (main study)

Evaluation criteria:

- A substance is considered positive if a dose-related and statistically significant increase in mutation rate in one or more strains of bacteria in the presence and/or absence of S9-mix in both experiments at sub-toxic dose levels is found.
- A substance is considered negative if the number of induced revertants compared to spontaneous revertants is less than twofold at each dose level employed, the intervals of which should be between 2 and 5 fold and extend to the limits imposed by toxicity, solubility or up to 5000 µg/ plate.

Statistics:

All data are statistically analysed using the methods recommended by UKEMS (Kirkland (Ed.): Statistical Evaluation of Mutagenecity Test Data", UKEMS Sub-committee on guidelines for Mutagenicity Testing. Report - Part III (1989)- Cambridge university Press).

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:

≥ 1250 µg/ plate

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

≥ 1250 µg/ plate

Vehicle controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

In an AMES test according to OECD/EC guidelines under GLP circumstances using 5 different Salmonella typhimurium strains with two independent repeats, Nisseki-SAS-40 was found not to be mutagenic with or without metabolic activation.

Executive summary:

SAS-40 was tested in the Salmonella typhimurium reverse mutation assay according to OECD/EC guidelines with five histidine-requiring strains of Salmonella typhimurium (TA1535, TA1537, TA1538, TA98 and TA100) with and without metabolic activation (S9 -mix). The test was performed in two independent experiments. The test substance did not induce a significant dose-related increase in the number of revertant (His+) kolonies in any of the strains. Both the solvent control and positive controls gave results within expected ranges. Cytotoxicity was observed at ≥ 1250 µg/ plate. Based on the results of this study it can be concluded that SAS-40 is not mutagenic in the Salmonella typhimurium reverse mutation assay.