Zinc bis(dibenzyldithiocarbamate)

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OTS 798.5265 (The Salmonella typhimurium Bacterial Reverse Mutation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Zinc bis(dibenzyldithiocarbamate)

EC Number:

238-778-0

EC Name:

Zinc bis(dibenzyldithiocarbamate)

Cas Number:

14726-36-4

Molecular formula:

C30H28N2S4Zn

IUPAC Name:

zinc bis(dibenzyldithiocarbamate)

Details on test material:

- Physical state: fine white powder
- Purity: 99.19% pure
- Storage condition of test material: Stored in the original container at room temperature and protected from light.

Method

Target gene:

DNA base pairs

Species / strain

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

S-9 mix

Test concentrations with justification for top dose:

50, 158, 500, 1580 and 5000 µg per plate.

Vehicle / solvent:

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

Controls

Controls 1

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Controls 2

Positive controls:

yes

Positive control substance:

benzo(a)pyrene

Controls 3

Positive controls:

yes

Positive control substance:

2-nitrofluorene

Controls 4

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Controls 5

Positive controls:

yes

Positive control substance:

9-aminoacridine

Controls 6

Positive controls:

yes

Positive control substance:

sodium azide

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Preincubation period: 2 days at 37°C

NUMBER OF REPLICATIONS: triplicate

DETERMINATION OF CYTOTOXICITY
- Method: examination for the presence of a background lawn of non-revertant colonies

Results and discussion

Test results

Key result

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

Positive controls validity:

valid

Additional information on results:

RANGE-FINDING/SCREENING STUDIES:
Preliminary toxicity test performed with a series of eight different concentrations of test material from 2.5 ug to 5 mg per plate, inoculated with an overnight culture of strain TA 98.
No visible thinning of the background lawn of non-revertant cells was obtained following exposure to ZDBzC. A top exposure level of 5 mg per plate was therefore selected for use in the main assays.

CYTOTOXICITY:
Inhibition of growth, observed as reduction in revertant colony numbers, occurred in all strains on at least one occasion of testing following exposure to ZDBzC at 5000 ug per plate, and in strain TA 100 only with ZDBzC at 1580 ug per plate.

Remarks on result:

other: all strains/cell types tested

Any other information on results incl. tables

Summary of the revertant colony means:

Plate N°		Addition (µg)	S-9mix: + present; - absent	Revertant colony means
				TA98(Test 1)	TA98(Test 2)	TA100(Test 1)	TA100(Test 2)	TA1535(Test 1)	TA1535(Test 2)	TA1537(Test 1)	TA1537(Test 2)
1	None; sterility check		+	0	0	0	0	0	0	0	0
2	ZDBzC sterility check	5000	-	0	0	0	0	0	0	0	0
3	ZDBzC	5000	+	22	30	42	20	7	10	3	4
4	ZDBzC	1580	+	36	31	73	50	13	12	6	7
5	ZDBzC	500	+	35	33	108	113	13	13	6	7
6	ZDBzC	158	+	34	34	112	112	14	13	8	6
7	ZDBzC	50	+	35	32	111	110	14	15	6	8
8	DMSO		+	37	32	110	110	13	13	8	7
9	ZDBzC	5000	-	19	14	34	20	14	8	2	2
10	ZDBzC	1580	-	30	29	64	39	14	14	6	6
11	ZDBzC	500	-	32	33	109	91	13	17	6	7
12	ZDBzC	158	-	35	34	110	109	14	15	7	7
13	ZDBzC	50	-	32	33	106	112	13	16	7	6
14	DMSO		-	36	31	110	111	14	16	8	8
15	Benzo(a)pyrene		-	31	26	104	102	12	16	6	6
16	Benzo(a)pyrene		+	260	393	590	470	846	494	218	171
17	2-Nitrofluorene		-	440	909	531	673	644	416	167	146
18	None; 10E-6 dilution of bacterial culture only		-	115	113	115	113	114	116	114	113