Bis(isopropyl) thioperoxydicarbonate

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:

The experiments were carried out between 10 December 1985 and 20 December 1985.

Reliability:

1 (reliable without restriction)

Justification for type of information:

AS DIXD is a known hydrolysis degradant of AS100, an AS100 study is being used as read-across for this shorter chain sulphide structural analogue.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1986

Report date:

1986

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Di-isopropyl xanthogen polysulphide

IUPAC Name:

Di-isopropyl xanthogen polysulphide

Test material form:

other: liquid batch

Details on test material:

Sponsor's identification : Robac AS100
Description : liquid
Batch number : 246041130005
Sample dated 12th February 2013

Method

Target gene:

Histidine for Salmonella.

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):

Not applicable

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 1538

Details on mammalian cell type (if applicable):

Not applicable.

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254 induced rat liver, S9 mix

Vehicle / solvent:

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

Controls

Controls 1

Untreated negative controls:

yes

Remarks:

Spontaneous mutation rates

Negative solvent / vehicle controls:

yes

Remarks:

hexane

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene (AA)

Controls 2

Untreated negative controls:

yes

Remarks:

Spntaneous mutation rates

Negative solvent / vehicle controls:

yes

Remarks:

hexane

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-nitrofluorene (NF), 9-aminoacridine (9-AC), N--ethyl-N''-nitro-Nnitrosoguanidine (ENNG)

Remarks:

Used without S9 mix

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION

- Exposure duration: 72 hrs

NUMBER OF REPLICATIONS: Triplicate plating.

DETERMINATION OF CYTOTOXICITY
- Method: Any toxic effects of the test substance are detected by a substantial reduction in revertant colony counts or by the absence of a complete background bacterial lawn.

Evaluation criteria:

The mean number of revertant colonies for all treatment groups is compared with those obtained for negative and positive control groups. The effect of metabolic activation is assessed by comparing the results obtained both in the presence and absence of the liver microsomal fraction for each treatment group.

Results and discussion

Test results

Test results 1

Species / strain:

other: 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 nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

The revertant colony counts for DIXT obtained in the dose range finding test are shown in Table 1 (see attached background material). DIXT was not toxic towards the tester strains. Therefore 5000 µg/plate was chosen as the top dose level in the mutation tests.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

See attached background material for:

Table 1: Dose range finding test on DIXT - revertant colony numbers obtained with bacterial strains TA 1535, TA 1537, TA 1538, TA 98 and TA100

Table 2: Test 1; DIXT - revertant colony counts obtained per plate using bacterial strains TA 1535, TA 1537, TA 1538, TA 98 and TA100

Table 3: Test 1; Mutability and sterility tests with bacterial strains TA 1535, TA 1537, TA 1538, TA 98 and TA100

Table 4: Test 2; DIXT - revertant colony counts obtained per plate using bacterial strains TA 1535, TA 1537, TA 1538, TA 98 and TA100

Table 5: Test 2; Mutability and sterility tests with bacterial strains TA 1535, TA 1537, TA 1538, TA 98 and TA100

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative with metabolic activation
negative without metabolic activation

It is concluded that no evidence of mutagenic potential of DIXT was obtained in this bacterial test system at the dose levels used.

Executive summary:

Introduction.

The object of the study was to assess the mutagenic potential of the test material in a bacterial system, following a test method based on OECD Guideline No. 471: Genetic Toxicology: Salmonella typhiumurium, Reverse Mutation Assay.

Methods.

Salmonella typhimuriumstrains TA 1535, TA 1537, TA 1538, TA 98 and TA 100 were used in the study.

The dose levels used were 5000, 500, 50 and 5 µg/plate in a dose range finding test, and 5000, 1500, 500, 150 and 50 µg/plate in the subsequent mutation tests.

Each dose level was tested in triplicate, both with and without metabolic activation (S9 mix).

Results.

In the dose range finding test, DIXT was not toxic towards the tester strains. Therefore 5000 µg/plate was chosen as the top dose level in the mutation tests.

No substantial increases in revertant colony numbers of any of the five tester strains were observed following treatment with DIXT at any dose level, either in the presence or absence of metabolic activation (S9 mix).

Conclusion.

It is concluded that no evidence of mutagenic potential of DIXT was obtained in this bacterial test system at th dose levels used.