dipropyl cyclohexane-1,2-dicarboxylate

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:

6th August 2015- 23rd September 2015

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

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:

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

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.5100 - Bacterial Reverse Mutation Test (August 1998)

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:

1,2-dipropyl cyclohexane-1,2-dicarboxylate

EC Number:

805-172-8

Cas Number:

65646-25-5

Molecular formula:

C14 H24 O4

IUPAC Name:

1,2-dipropyl cyclohexane-1,2-dicarboxylate

Test material form:

other: Liquid

Details on test material:

- Name of test material (as cited in study report): CHP
- Physical state: Colourless Liquid
- Analytical purity: 98.6%
- Lot/batch No.:ST111209
- Expiration date of the lot/batch:31 December 2016
- Storage condition of test material:Room temperature (ca. 20°C), in the dark, under gaseous nitrogen

Method

Species / strain

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2

Metabolic activation:

with and without

Metabolic activation system:

Sprague-Dawley-induced rat liver S9

Test concentrations with justification for top dose:

First main test with metabolic activation: 5-5000 micrograms/plate
First main test without metabolic activation: 5-5000 micrograms/plate
Second main test with metabolic activation: 50-5000 micrograms/plate
Second main test without metabolic activation: 50-5,000 micrograms/plate
Additonal main test with metabolic activation: 0.5-1500 micrograms/plate
Additonal main test without metabolic activation: 0.5-1500 micrograms/plate

Vehicle / solvent:

DMSO

Controls

Controls 1

Untreated negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

Controls 2

Positive controls:

yes

Positive control substance:

9-aminoacridine

Controls 3

Positive controls:

yes

Positive control substance:

other: 2-Nitrofluorene

Controls 4

Positive controls:

yes

Positive control substance:

other: 4-Nitroquinoline-1-oxide

Evaluation criteria:

For a test to be considered valid, the mean of the vehicle control revertant colony numbers for each strain should lie within or close to the current historical control range for the laboratory unless otherwise justified by the Study Director. The historical range is maintained as a rolling record over a maximum of five years. Also, the positive control compounds must induce an increase in mean revertant colony numbers of at least twice (three times in the case of strains TA1535 and TA1537, which have relatively low spontaneous reversion rates) that of the concurrent vehicle controls. Meanviable cell counts in the 10-hour bacterial cultures must be at least 109/mL.

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Toxicity (observed as thinning of the background lawn of non-revertant colonies, together with a reduction in revertant colony numbers) was seen in strain TA1537 following exposure to CHP at 5000 μg/plate in the presence of S9 mix.

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Positive controls validity:

valid

Test results 3

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks on result:

other: other: First Test

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

First test Toxicity (observed as thinning of the background lawn of non-revertant colonies, together with a reduction in revertant colony numbers) was seen in strain TA1537 following exposure to CHP at 5000 μg/plate in the presence of S9 mix. A maximum exposure concentration of 5000 μg/plate was, therefore, selected for use in the second test. No substantial increases in revertant colony numbers over control counts were obtained with any of the tester strains following exposure to CHP at any concentration up to and including 5000 μg/plate in either the presence or absence of S9 mix.

Second test Toxicity (observed as thinning of the background lawn of non-revertant colonies, together with a reduction in revertant colony numbers) was seen in strains TA100, TA1535 and TA1537 from 150 μg/plate in the absence of S9 mix. In strain WP2 uvrA (pKM101), toxicity (observed as a reduction in revertant colony numbers) was seen from 1500 μg/plate in the absence of S9 mix. In the presence of S9 mix, toxicity (observed as thinning of the background lawn of non-revertant colonies, together with a reduction in revertant colony numbers) was seen in strain TA1535 at 5000 μg/plate and in strain TA1537 at 500, 1500 and 5000 μg/plate. As an insufficient amount of non-toxic concentrations was obtained with strains TA100 and TA1535 without metabolic activation and with strain TA1537 with and without metabolic activation, an additional test was performed. A maximum exposure concentration of 1500 μg/plate was selected for use in the additional test. No substantial increases in revertant colony numbers over control counts were obtained with any of the tester strains following exposure to CHP at any concentration up to and including 5000 μg/plate in either the presence or absence of S9 mix.

Additional test Toxicity (observed as thinning of the background lawn of non-revertant colonies and/or a reduction in revertant colony numbers) was seen in strain TA1535 from 50 μg/plate and in strains TA100 and TA1537 from 150 μg/plate in the absence of S9 mix. In the presence of S9 mix, toxicity (observed as thinning of the background lawn of non-revertant colonies) was seen in strain TA1537 at 1500 μg/plate. No substantial increases in revertant colony numbers over control counts were obtained with any of the tester strains following exposure to CHP at any concentration up to and including 1500 μg/plate in either the presence or absence of S9 mix.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

It was concluded that CHP showed no evidence of mutagenic activity in this bacterial system under the test conditions employed.

Executive summary:

No evidence of mutagenic activity was seen at any concentration of CHP in either mutation test. The concurrent positive controls verified the sensitivity of the assay and the metabolising activity of the liver preparations. The mean revertant colony counts for the vehicle controls were within or close to the current historical control range for the laboratory. It was concluded that CHP showed no evidence of mutagenic activity in this bacterial system under the test conditions employed.