4-bromoanisole

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

The mutagenic potential of para bromoanisole was tested in vitro in a bacterial reverse mutation assay. The test was performed similar to the OECD guideline 417 (Ames test), but a modification was used. 10 tester strains, including the ones recommended in the OECD 417 guideline, were tested. However, instead of definite concentrations, concentration ranges (0.1 - 1, 1 - 10, 10 - 100 and 100 - 1000 µg/ml) of the test substance were tested. Positive and negative controls were included and the test was performed with and without metabolic activation. About 854 chemicals next to para bromoanisole were tested in the same study. According to the authors of the study, p-Bromoanisole showed no mutagenic potential in the concentation range of 0.1 to 1000 µg/mL with and without metabolic activation. The study was considered to be reliable with restrictions.

Link to relevant study records

Reference

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:

1979

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

At the time of the study no GLP-rules had been established; therefore the study is a non-GLP study. A modification of Ames test was used and a detailled documentation of testing procedure is given. The testing procedure was similar to OECD guideline 471; positive and negative controls were included; 10 tester strains including the ones recommended by OECD 471, were used in the test; no definite exposure concentrations were tested, but a concentration-gradient; no data on analytical results of the test substance, no individual data and no data on the storage of the individual values are given. The reputation of the test laboratory allows to speculate that these data exist and have been stored.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Principles of method if other than guideline:

Screening is done using a concentration gradient of the test substance and 10 tester strains on one Agar plate, 8 Agar plates were prepared for each substance: with concentration gradients approx. 0.1-1, 1-10, 10-100 and 100 to 1000 µg/ml and with and without metabolic activation; hence, no definite concentrations were tested; as result the upper and lower concentrations tested or those with a positive result are reported.

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Target gene:

- Dependant on the strain tested; histidine in many cases

Species / strain / cell type:

E. coli, other: WP2 tryptophan

Species / strain / cell type:

E. coli WP2 uvr A

Species / strain / cell type:

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

Species / strain / cell type:

S. typhimurium, other: G46, C3076, D3052 and TA1538

Metabolic activation:

with and without

Metabolic activation system:

mixture of rat liver enzymes from animals treated with Aroclor

Test concentrations with justification for top dose:

- No distinct concentration tested, but testing of four concentration gradients: approx. 0.1-1, 1-10, 10-100 and 100 to 1000 µg/ml

Vehicle / solvent:

dimethyl sulfoxide, water or dimethoxyethane

Untreated negative controls:

yes

Negative solvent / vehicle controls:

not specified

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

2-acetylaminofluorene

other: streptozotocin

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION

Exposure duration:48 hr



DETERMINATION OF CYTOTOXICITY
yes

Evaluation criteria:

- The concentration range over which chemically induced mutant colonies are present is recorded

Statistics:

- Operator judgement
- Experienced personel

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

not specified

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

The single values of the testing results are missing. The result "negative" is only listed in a table(no. 6).

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Conclusions:

Interpretation of results (migrated information):
negative

According to the authors of the study, a negative result was obtained for p-Bromoanisole in the concentation range of 0.1 to 1000 µg/mL with and without metabolic activation.

Executive summary:

The mutagenic potential of para bromoanisole was tested in vitro in a bacterial reverse mutation assay. The test was performed similar to the OECD guideline 417 (Ames test), but a modification was used. 10 tester strains, including the ones recommended in the OECD 417 guideline, were tested. However, instead of definite concentrations, concentration ranges (0.1 - 1, 1 - 10, 10 - 100 and 100 - 1000 µg/ml) of the test substance were tested. Positive and negative controls were included and the test was performed with and without metabolic activation. About 854 chemicals next to para bromoanisole were tested in the same study. According to the authors of the study, p-Bromoanisole showed no mutagenic potential in the concentation range of 0.1 to 1000 µg/mL with and without metabolic activation. The study was considered to be reliable with restrictions.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Additional information from genetic toxicity in vitro:

Justification for selection of genetic toxicity endpoint
The study by McMahon et al 1979 was considered reliable with restrictions.