1,8-Naphthalenediol, 1,8-dibenzoate

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

No increase in bacterial reverse mutants was observed with or without metabolic activation.

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline and GLP study

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Qualifier:

according to guideline

Guideline:

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

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.5100 - Bacterial Reverse Mutation Test (August 1998)

GLP compliance:

yes (incl. QA statement)

Remarks:

testing lab.

Type of assay:

bacterial reverse mutation assay

Target gene:

Salmonella typhimurium: histidine
Escherichia coli WP2 uvrA: tryptophan

Species / strain / cell type:

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

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

phenobarbital/b-naphtoflavone

Test concentrations with justification for top dose:

Standard plate test and Preincubation test: 0; 33; 100; 333; 1 000; 2500 and 5000 μg/plate

Vehicle / solvent:

The test substance was dissolved in DMSO. To achieve a clear solution of the test substance in the vehicle, the test substance preparation was treated with ultrasonic waves and shaken thoroughly. The further concentrations were diluted according to the planned doses. All test substance formulations were prepared immediately before administration.

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

9-aminoacridine

N-ethyl-N-nitro-N-nitrosoguanidine

other: 2-aminoanthracene (with S9 mix), 4-nitro-o-phenylenediamine (without S9 mix)

Remarks:

with S9 mix: 2-AA (all strains); without S9 mix: MNNG (TA 1535, TA100), NOPD (TA 98), AAC (TA 1537), 4-NQO (E. coli)

Details on test system and experimental conditions:

1st Experiment
Strains: TA 1535, TA 100, TA 1537, TA 98, E. coli WP2 uvrA
Doses: 0; 33; 100; 333; 1 000; 2 500 and 5 000 μg/plate
Type of test: Standard plate test with and without S9 mix
Number of plates: 3 test plates per dose or per control

2nd Experiment
Strains: TA 1535, TA 100, TA 1537, TA 98, E. coli WP2 uvrA
Doses: 0; 33; 100; 333; 1 000; 2 500 and 5 000 μg/plate
Type of test: Preincubation test with and without S9 mix
Number of plates: 3 test plates per dose or per control
Reason: No mutagenicity was observed in the standard plate test.

3rd Experiment
Strains: TA 98
Doses: 0; 33; 100; 333; 1 000; 2 500 and 5 000 μg/plate
Type of test: Preincubation test with and without S9 mix
Number of plates: 3 test plates per dose or per control
Reason: Due to contaminations observed in the Preincubation test with TA 98 an evaluation of this tester strain was not possible. The 2nd Experiment with TA 98 was not reported.

Evaluation criteria:

Individual plate counts, the mean number of revertant colonies per plate and the standard deviations were given for all dose groups as well as for the positive and negative (vehicle) controls in all experiments. In general, six doses of the test substance were tested with a maximum of 5 mg/plate, and triplicate plating was used for all test groups at least in the 1st Experiment. The titer was generally determined only in the experimental parts with S9 mix both for the negative controls (vehicle only) and for the two highest doses in all experiments. Toxicity detected by a decrease in the number of revertants, clearing or diminution of the background lawn, or reduction in the titer. Toxicity was recorded for all test groups both with and without S9 mix in all experiments. Precipitation of the test material was recorded and as long as it did not interfere with the colony scoring, 5 mg/plate was generally selected and analyzed as the maximum dose to detect possible mutagenic impurities.

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:

starting at 1000 ug/plate (standard plate test) or 2500 µg/plate (in preincubation test)

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

starting at 1000 ug/plate (standard plate test) or 2500 µg/plate (in preincubation test)

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

No increase in bacterial reverse mutants was observed with Thane 003-6, either in the standard plate test or the preincubation test. Precipitation of the test substance was found starting at 333 ug/plate with and without S9 mix.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Additional information from genetic toxicity in vitro:

An Ames test according to OECD 471 was performed with Salmonella TA 1535, TA 100, TA 1537, TA 98, and E. coli WP2 uvrA (BASF, 2014). The test substance was used at up to 5 mg/plate, 3 test plates per dose/control. In a first experiment, a standard plate test with and without metabolic activation was performed; no increase of bacterial revertant colonies was detected after 48 -72 hours. Therefore, the 2nd and 3rd experiment were performed as preincubation assays, also testing up to 5 mg test substance/plate with and without metabolic activation. Also under these conditions, no increase of bacterial colonies was observed. Therefore, test substance did not facilitate or enhance baterial mutagenicity in both standard plate and preincubation assay in doses up to 5 mg/plate with and without metabolic activation.

Precipitates were found at concentrations of 333 µg/plate and higher, and bacterial toxicity started at 1000 µg/plate in the standard plate assay and 2500 µg/plate in the preincubation assay.

Justification for selection of genetic toxicity endpoint
GLP and guideline study

Justification for classification or non-classification

According to Regulation EC 1272/2008 (CLP), Thane 003-6 does not require classification for genetic toxicity.