Sodium 5-N-butylbenzotriazole

Genetic toxicity: in vitro

Administrative data

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:

23.08.1988 - 12.09.1988

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Sodium 5-N-butylbenzotriazole

EC Number:

404-450-2

EC Name:

Sodium 5-N-butylbenzotriazole

Cas Number:

118685-34-0

Molecular formula:

CCCCc1ccc2c(c1)nnn2[Na]

IUPAC Name:

sodium 5-butyl-1H-1,2,3-benzotriazol-1-ide

Details on test material:

Name of test material: Butyl benzotriazole-sodium salt (referred to in the study as Butyl BZT)
Physical state: brown liquid
Purity: 37% aqueous solution
Strage condition: stored at room temperature

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1538

Additional strain / cell type characteristics:

other: Defective in DNA repair capacity (Δ uvrB), defective lipopolysaccharide barrier on the cell wall (rfa)

Species / strain 2

Species / strain / cell type:

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

Additional strain / cell type characteristics:

other: Defective in DNA repair capacity (Δ uvrB), defective lipopolysaccharide barrier on the cell wall (rfa). Strains TA 98 and TA 100 also contain a resistance transfer factor (plasmid pKM 101)

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254 induced rat liver homogenate S-9

Test concentrations with justification for top dose:

Dose range finding test:
100, 10, 1, 0.1% Butyl benzotriazole-sodium salt 37% solution
Equivalent to 37000, 3700, 370, 37 µg/plate of Butyl benzotriazole-sodium salt

Mutation tests:
1, 0.3, 0.1, 0.03, 0.01% Butyl benzotriazole-sodium salt 37% solution
Equivalent to 370, 111, 37, 11.1, 3.7 µg/plate of Butyl benzotriazole-sodium salt

Vehicle / solvent:

Solvent: Water

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Remarks:

With S-9 mix, at 2 µg/plate for strains TA 1535 and TA 1537, at 0.5 µg/plate for strains TA 1538 and TA 98, at 1 µg/plate for strain TA 100

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

N-ethyl-N-nitro-N-nitrosoguanidine

Remarks:

Without S-9 mix, at 5 µg/plate for strain TA 1535, at 3 µg/plate for strain TA 100

Controls 3

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

Without S-9 mix, at 80 µg/plate for strain TA 1537

Controls 4

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

2-nitrofluorene

Remarks:

Without S-9 mix, at 2 µg/plate for strain TA 1538, at 1 µg/plate for strain TA98

Results and discussion

Test results

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:

(A 1% stock solution was chosen as the top dose level in the mutation tests)

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

No substantial increases in revertant colony numbers of any of the five tester strains were observed following treatment with Butyl benzotriazole-sodium salt at any dose level, either in the presence or absence of metabolic activation (S-9 mix).

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 with metabolic activation
negative without metabolic activation

The revertant colony counts for Butyl benzotriazole-sodium salt obtained in the dose range finding test are shown in Table 1 of attached study report. Butyl benzotriazole-sodium salt was toxic towards the tester strains at the higher dose Ievels. Therefore a 1% stock solution was chosen as the top dose level in the mutation tests.

The mean number of revertant colonies, together with the individual plate counts for Butyl benzotriazole-sodium salt obtained in the flrst mutation test with tester strains TA 1535, TA 1537, TA 1538, TA 98 and TA 100 are shown in Table 2 of study report. Positive control mutability checks are shown in Table 3 of study report.

The mean number of revertant colonies, together with the individual plate counts for Butyl benzotriazole-sodium salt obtained in the second mutation test with tester strains TA 1535, TA 1537, TA 1538, TA 98 and TA 100 are shown in Table 4 of study report. Positive control mutabÍIity checks are shown in Table 5 of study report.

No substantial increases in revertant colony numbers of any of the five tester strains were observed following treatment with Butyl benzotriazole-sodium salt at any dose level, either in the presence or absence of metabolic activation (S-9 mix).

It is'concluded that no evidence of mutagenic potential of Butyl benzotriazole-sodium salt was obtained in this bacterial test system at the dose levels used.

Executive summary:

In this in vitro assessment of the mutagenic potential of Butyl benzotriazole-sodium salt, Slamonella typhimurium (strains TA 1535, TA1537, TA1538, TA 98 and TA 100) were exposed to the test substance, diluted in water whixh was also used as negatice control.

Tests were performed, in presence and abscence of metabolic activation system (Aroclor 1254 induced rat liver homogenate S-9). In the preliminary toxicity test, toxicity was observed at dose levels upper than 370 µg/plate of Butyl benzotriazole-sodium salt (1% of Butyl benzotriazole-sodium salt 37% solution). A top dose level of 370 µg/plate of Butyl benzotriazole-sodium salt was chosen for the mutation study. Other dose levels used in the mutation assays were 111, 37, 11.1 and 3.7 µg/plate of Butyl benzotriazole-sodium salt (respectively 0.3, 0.1, 0.03 and 0.01% of Butyl benzotriazole-sodium salt 37% solution)

No evidence of mutagenic activity was seen at any dose level of Butyl benzotriazole-sodium salt ineither mutation test.

The concurrent positive control compounds demonstrated the sensitivity of the assay and the the metabolising activity of the liver preparation.

It is'concluded that no evidence of mutagenic potential of Butyl benzotriazole-sodium salt was obtained in this bacterial test system at the dose levels used.