Nickel bis(dibutyldithiocarbamate)

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14 Jul 2017 to 20 Jul 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

21 July 1997

GLP compliance:

yes (incl. QA statement)

Remarks:

Testing laboratory: Triskelion B.V., Utrechtseweg 48, 3704 HE Zeist, The Netherlands

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Nickel bis(dibutyldithiocarbamate)

EC Number:

237-696-2

EC Name:

Nickel bis(dibutyldithiocarbamate)

Cas Number:

13927-77-0

Molecular formula:

C18-H36-N2-Ni-S4

IUPAC Name:

Nickel(II) Dibutyldithiocarbamate

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Name as mentioned in test report: Nickel dibutyldithiocarbamate
- Batch No. of test material: 70500102
- Expiration date of the lot/batch: 25 May 2019
- Purity test date: set to 100%
- Appearance: dark green powder

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: ambient temperature (15-25 ⁰C)

Method

Target gene:

- S. typhimurium: his
- E. coli: trp

Species / strain

Species / strain 1

Species / strain / cell type:

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

Additional strain / cell type characteristics:

not applicable

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

S9 mix from Aroclor 1254 induced rats livers

Test concentrations with justification for top dose:

MAIN EXPERIMENT
- Strains TA98, TA100, TA1535, TA1537 and WP2 uvrA, with and without S9-mix: 62, 185, 556, 1667, 5000 μg/plate

Vehicle / solvent:

- Vehicle used: DMSO
- Justification for choice of vehicle: the test substance appeared to be poorly soluble in the aqueous solvent phosphate buffered saline

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: See “Any other information on materials and methods inc. tables”

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48-72 hours at ca. 37 ⁰C

NUMBER OF REPLICATIONS:
3 plates/dose

Evaluation criteria:

see section "Any other information on materials and methods incl. tables"

Statistics:

No statistical analysis was performed.

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium, other: TA 1535, TA 100, TA 1537, TA 98

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 applicable

Positive controls validity:

valid

Test results 2

Key result

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 applicable

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: A dose related precipitation was observed after adding the test substance to the molten top agar and at the plates at all concentrations tested for all strains. At and above 556 μg/plate the precipitation could be observed by macroscopically. This precipitation was considered not to affect counting of the revertants. At and above 1667 μg/plate a slightly more dense background lawn of bacterial growth compared to the concomitant control plates was observed at all strains.

VALIDATION CRITERIA
The mean numbers of his+ and trp+ revertant colonies of the negative controls used were within the acceptable range in all strains and the positive controls gave the expected increase in the mean numbers of revertant colonies. Therefore, the test was considered valid.

ADDITIONAL INFORMATION ON CYTOTOXICITY:
No toxicity was observed in any strain, this was evidenced by an absence of a clearing of the background lawn of bacterial growth compared to the negative controls, no decrease in the mean number of revertants was observed and pinpoint colonies did not occur.