Tetrakis(tritolyl phosphite )nickel

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:

From 30 AUG 2010 to 9 SEP 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

(minor deviations, not affecting the study results)

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

(minor deviations, not affecting the study results)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Tetrakis(tritolyl phosphite )nickel

EC Number:

252-777-2

EC Name:

Tetrakis(tritolyl phosphite )nickel

Cas Number:

35884-66-3

Molecular formula:

C84H84NiO12P4

IUPAC Name:

tetrakis(tris(4-methylphenyl) phosphite) nickel

Details on test material:

- Name of test material (as cited in study report): Ni (TTP)4
- Description: Black liquid (determined at NOTOX)
- Storage condition of test material: At room temperature protected from light under nitrogen
- Stability under storage conditions: Stable

Method

Target gene:

His (Salmonella strains TA1537, TA98, TA1535, TA100)
Trp (E. coli strain WP2uvrA)

Species / strain

Species / strain 1

Species / strain / cell type:

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

Details on mammalian cell type (if applicable):

- Type and identity of media:
- Properly maintained: yes
- The Salmonella typhimurium strains were regularly checked to confirm their histidine requirement, crystal violet sensitivity, ampicillin resistance (TA98 and TA100), UV-sensitivity and the number of spontaneous revertants.

Additional strain / cell type characteristics:

other: Each strain contained the following additional mutations: rfa: deep rough (defective LPS cellcoat); gal: mutation in the galactose metabolism; chl: mutation in nitrate reductase; bio: defective biotin synthesis; uvrB: loss of the excision repair system

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Details on mammalian cell type (if applicable):

- Properly maintained: yes/no
The strain was regularly checked to confirm the tryptophan-requirement, UV-sensitivity and the number of spontaneous revertants.

Metabolic activation:

with and without

Metabolic activation system:

Rat liver S9 from phenobarbital/ß-naphthoflavone induced adult male Wistar rats

Test concentrations with justification for top dose:

Range finding experiment: 3, 10, 33, 100, 333, 1000, 3333 and 5000 µg/mL (TA100 and WP2 uvr A) with and without metabolic activation, in triplicates
Experiment 1: 3, 10, 33, 100, 333, 1000 µg/mL for all strains with and without metabolic activation, in triplicates
Experiment 2: 10, 33, 100, 333, 1000 µg/mL for all strains with and without metabolic activation, in triplicates

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

without metabolic activation

Migrated to IUCLID6: for TA 1535

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

without metabolic activation

Migrated to IUCLID6: for TA 1537

Controls 3

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

2-nitrofluorene

Remarks:

without metabolic activation

Migrated to IUCLID6: for TA 98

Controls 4

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

methylmethanesulfonate

Remarks:

without metabolic activation

Migrated to IUCLID6: for TA 100

Controls 5

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

Remarks:

without metabolic activation

Migrated to IUCLID6: for WP2 uvr A

Controls 6

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracen for all strains

Remarks:

with metabolic activation

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Preincubation period: no
- Exposure duration: 48 +/- 4 h

DETERMINATION OF CYTOTOXICITY
- Method: other: reduction of bacterial lawn, increase in the size of the microcolonies and reduction of the revertant colonies

Evaluation criteria:

Acceptability criteria:
The Salmonella typhimurium reverse mutation assay and/or Escherichia coli reverse mutation assay is considered acceptable if it meets the following criteria:
a) The negative control data (number of spontaneous revertants per plate) should be within the laboratory historical range for each tester strain.
b) The positive control chemicals should produce responses in all tester strains, which are within the laboratory historical range documented for each positive control substance. Furthermore, the mean plate count should be at least three times the concurrent vehicle control group mean.
c) The selected dose range should include a clearly toxic concentration or should exhibit limited solubility as demonstrated by the preliminary toxicity range-finding test or should extend to 5 mg/plate.


Evaluation criteria:
A test substance is considered negative (not mutagenic) in the test if:
a) The total number of revertants in tester strain TA100 is not greater than two (2) times the concurrent control, and the total number of revertants in tester strains TA1535, TA1537, TA98 or WP2uvrA is not greater than three (3) times the concurrent control.
b) The negative response should be reproducible in at least one independently repeated experiment.

A test substance is considered positive (mutagenic) in the test if:
a) The total number of revertants in tester strain TA100 is greater than two (2) times the concurrent control, or the total number of revertants in tester strains TA1535, TA1537, TA98 or WP2uvrA is greater than three (3) times the concurrent control.
b) In case a repeat experiment is performed when a positive response is observed in one of the tester strains, the positive response should be reproducible in at least one independently repeated experiment.
The preceding criteria were not absolute and other modifying factors might enter into the final evaluation decision.

Statistics:

No formal hypothesis testing was done.

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:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

All bacterial strains showed negative responses over the entire dose range, i.e. no significant dose-related increase in the number of revertants in two independently repeated experiments.
The negative and strain-specific positive control values were within the laboratory historical control data ranges indicating that the test conditions were adequate and that the metabolic activation system functioned properly.

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

Under the conditions of this study all bacterial strains showed negative responses over the entire dose range, i.e. no significant dose-related increase in the number of revertants.

Executive summary:

The test item was subject to the Salmonella typh. reverse mutation assay with four histidine­requiring strains of Salmonella typh. (TA1535, TA1537, TA98 and TA100) and the E. coli reverse mutation assay with the tryptophan-requiring strain WP2uvrA. The test item concentrations in the two independent main experiments were 10, 33, 100, 333 and 1000 µg/mL in the presence and absence of metabolic activation. The test item precipitated on the plates at the top dose of 1000 µg/plate. No cytotoxicity was observed at this concentration.

All bacterial strains showed negative responses over the entire dose range, i.e. no significant dose-related increase in the number of revertants in two independently repeated experiments. The negative and strain-specific positive control values were within the laboratory historical control data ranges indicating that the test conditions were adequate and that the metabolic activation system functioned properly.

Based on the results of this study it is concluded that the test item was not mutagenic in the Salmonella typhimurium reverse mutation assay and in the Escherichia coli reverse mutation assay.