Borate(1-), tris(acetato-.kappa.O)hydro-, sodium, (T-4)-

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Genetic toxicity in bacteria: negative (OECD 471) Cytogenicity in mammalian cells: negative (OECD 473) Gene mutation in mammalian cells: negative (Boric acid, NTP protocal comp. OECD 476)

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:

2004-07-14 - 2004-11-17

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD guideline study according GLP

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Hessisches Ministerium für Umwelt, ländliche Raum und Umweltschutz, 2002

Type of assay:

bacterial reverse mutation assay

Target gene:

Salmonella typhiumurium: his
E. coli: trp

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:

S9 mix prepared form Phenobarbital/beta-Naphtoflavone induced rat liver

Test concentrations with justification for top dose:

Experiment I: 3, 10, 33, 100, 333, 1000, 2500 and 5000 µg/plate
Experiment II: 33, 100, 333, 1000, 2500 and 5000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: Based on its solubility properies and relative non-toxicity to bacteria.

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

sodium azide

methylmethanesulfonate

other: 4-nitro-o-phenylene-diamine; 2-aminoanthracene

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation); preincubation

DURATION
- Preincubation period: 60 min, 37°C
- Exposure duration: at least 48 h, 37°C

SELECTION AGENT (mutation assays): Ampicillin, 25 µg/mL

NUMBER OF REPLICATIONS: 3/concentration

DETERMINATION OF CYTOTOXICITY
- Method: relative total growth

Evaluation criteria:

A test item was considered as a mutagen if a biological relevant increase in the number of revertants exceeding the threshold of twice (TA 98, TA100, WPA2) uvrA) or three times (TA 1535 and TA1537) the colony number of the solvent control as observed.
A dose dependent increase was considered biological relevant if the threshold exceeded at more than one concentration.
An increase exceeding the threshold at only one concentration is judged as biological relevant if reproduced in an independent second experiment.
A dose dependent increase in the number of revertant colonies below the threshold was regarded as an indication of a mutagenic potential if reproduced in an independent second experiment. However, whenever the colony number remained within historical range of negative and solvent controls such an increase was not considered biologically relevant.

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:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Conclusions:

Interpretation of results (migrated information):
negative

Sodium triacetoxyborohydride did not induce an increase in the number of revertanst in Salmonella typhimurium and Escherichia coli upt o concentration of 5000 µg/plate. Thus it was found to be non mutagenic under conditions of this test.

Executive summary:

Genetic toxicity of Sodium triacetoxyborohydride was tested in a GLP study performed according OECD 471, where Salmonella typhimurium strains TA1535, TA1537, TA98 and TA98 and Escherichia coli WP2 uvrA were treated with substance concentration of 3, 10, 33, 100, 333, 1000, 2500 and 5000 µg/plate in experiment I and concentrations of 33, 100, 333, 1000, 2500 and 5000 µg/plate in experiment II with and without metabolic activation, respectively. As no increase in number of revertants was noted in all strains and at all concentrations, Sodium triacetoxyborohydride was found to be non mutagenic under conditions of this test.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Additional information from genetic toxicity in vitro:

Genetic toxicity of Sodium triacetoxyborohydride in bacteria was tested in a GLP study performed according OECD 471, where Salmonella typhimurium strains TA1535, TA1537, TA98 and TA98 and Escherichia coli WP2 uvrA were treated with substance concentration of 3, 10, 33, 100, 333, 1000, 2500 and 5000 µg/plate in experiment I and concentrations of 33, 100, 333, 1000, 2500 and 5000 µg/plate in experiment II with and without metabolic activation, respectively. As no increase in number of revertants was noted in all strains and at all concentrations, Sodium triacetoxyborohydride was found to be non mutagenic under conditions of this test.

Sodium triacetoxyborohydride was tested in a GLP study performed according to OECD 473, where V79 cells were treated with concentrations up to 2150 µg/mL dissolved in DMSO for 4, 18 and 28 h without metabolic activation and for 4 h with metabolic activation (S9 mix), respectively. Since no structural chromosome aberrations were induced in V79 cells when treated up to 2150 µg/mL with and without metabolic activation, while the positive controls EMS and CPA did, Sodium triacetoxyborohydride was found to be non-clastonic under conditions of this test.

Boric acid was tested for inducing gene mutation in mammalian cells in a GLP study performed according to NTP protocol which is comparable to OECD guideline. Well maintained mouse lymphoma L5178Y cells were treated with boric acid up concentration of 5000 µg/mL with and without metabolic activation by a S9 mix for 4 hours. Since no toxicity and no increase in frequency was observed, boric acid was regarded to be non-mutagenic in mammalian cells.

Justification for selection of genetic toxicity endpoint
Reliable OECD guideline study according GLP

Justification for classification or non-classification

The available data on genetic toxicity of the test substance do not meet the criteria for classification according to Regulation (EC) 1272/2008, and are therefore conclusive but not sufficient for classification.