Reaction mass of cyclohexanol and cyclohexanone

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Negative results have been obtained with both constituents of the reaction mass.

Link to relevant study records

Reference

Reference 1

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Comparable to guideline study (OECD 471) with acceptable restrictions (limited documentation, no data on substance purity, prior to GLP, aminoanthracene was used as sole indicator of the efficacy of S9 mix, no E.coli or TA 102 and no TA 100 srains tested)

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

- limited description of test substance, no E. coli strain tested, TA 102, and TA 100 strain not tested, 2 Aminoanthracene was sole indicator used to provide information of the efficacy of S9)

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Target gene:

His Operon

Species / strain / cell type:

other: Salmonella typhimurium TA98, TA1535, TA1537, TA1538

Metabolic activation:

with and without

Metabolic activation system:

cofactor supplemented post-mitochondrial fraction (S9), prepared from the livers of rats

Test concentrations with justification for top dose:

500, 1000, 2500, 5000, 7500, 10000, 15000 ug/plate

Vehicle / solvent:

ethanol

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

other: WITH S9: 2 Aminoanthracene (2AA) (TA1538, TA98, TA1535 and 1537). WITHOUT S9: MNNG - H-Methyl-N'-nitro-H-nitrosoguanidine, (TA1535); 2-Nitrofluorene (TA1538 and TA 98); 9-aminoacridine (9AAD)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)


DURATION
- Exposure duration: 48h
- Temperature: 37°C

SELECTION AGENT (mutation assays): L-histidine

NUMBER OF DUPLICATES: 2

DETERMINATION OF CYTOTOXICITY
Prior to testing for mutagenicity, the compound was tested for toxicity to the tester strains
- Method: no data

POSITIVE CONTROLS
WITH S9: 2 Aminoanthracene (2AA); 10µg/plate (TA1538 and TA98), 100µg/plate (TA1535 and 1537)
WITHOUT S9: MNNG - H-Methyl-N'-nitro-H-nitrosoguanidine, 2µg/plate (TA1535); 2-Nitrofluorene 25 µg/plate (TA1538 and TA 98); 9-aminoacridine (9AAD) 50 µg/plate (TA1537)

Species / strain:

other: Salmonella typhimurium TA98, TA1535, TA1537, TA1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Additional information on results:

ADDITIONAL INFORMATION ON CYTOTOXICITY:
with S9: >= 7500 µg/plate in TA1537 and >= 10000µg/plate for TA98;
without S9: >= 7500 µg/plate in TA1537 and TA 98 >= 10000µg/plate for TA1538

Remarks on result:

other: other: Salmonella typhimurium TA98, TA1535, TA1537, TA1538

Remarks:

Migrated from field 'Test system'.

Table of Revertant Factors

Strain	Metabolic activation system	Duplicates	revertant factor range	revertant factor Positive control	dose dependency	Cytotoxicity	Assessment
TA 1535	no	2	0.81-1.4	93.8	no	no	negative
	yes	2	0.6-1.2	25.4	no	no	negative
TA 1537	no	2	1.1-1.4	36.2		> = 7500 µg/plate	negative
	yes		0.8-1.2	26	no	> = 7500 µg/plate	negative
TA 1538	no	2	0.7-1.0	131.6		no	negative
	yes		0.8-1.1	93.8	no	no	negative
TA 98	no	2	0.92-1.0	108	no	> = 7500 µg/plate	negative
	yes	2	0.95-1.3	90.9	no	> = 10000 µg/plate	negative

Assessment using OECD 471 guideline criteria

Reference 2

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes (incl. QA statement)

Remarks:

testing lab.

Type of assay:

bacterial reverse mutation assay

Target gene:

S. typhimurium strains and E. coli

Species / strain / cell type:

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

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

rat liver S-9 mix

Test concentrations with justification for top dose:

10 - 5000 ug/plate (Standard Plate Test); 10 - 1000 ug/plate (PreIncubation Test)

Vehicle / solvent:

water

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

other: with S-9 mix: 2-aminoanthracene; without S-9 mix: N-methyl-N'-nitro-N-nitrosoguanidine, 4-nitro-o-phenylendiamine, 9-aminoacridine and 4-nitroquinoline-N-oxide

Details on test system and experimental conditions:

Bacterial test strains were used, both in the standard plate test and in the preincubation test, both in the presence and absence of metabolic activation (+S9, -S9, respectively). DMSO was used as solvent. Three test plates per dose or per control were run in each of the 3 experiments.

Evaluation criteria:

The test chemical is considered positive in this assay if the following criteria are met:
• A dose-related and reproducible increase in the number of revertant colonies, i.e. about doubling of the spontaneous mutation rate in at least one tester strain either without S-9 mix or after adding a metabolizing system.
A test substance is generally considered nonmutagenic in this test if:
• The number of revertants for all tester strains were within the historical negative control range under all experimental conditions in two experiments carried out independently of each other.

Statistics:

-

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

Untreated negative controls validity:

valid

Positive controls validity:

valid

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

SOLUBILITY: No precipitation of the test substance was found.
TOXICITY: A bacteriotoxic effect was observed depending on the strain and test conditions from about 100 ug - 2,500 ug/plate onward.
MUTAGENICITY: An increase in the number of his+ or trp+ revertants was not observed in the standard plate test or in the preincubation test either without S-9 mix or after the addition of a metabolizing system.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Conclusions:

Interpretation of results (migrated information):
negative

According to the results of the present study, the test substance 2-Cyclohexenone pure calc. 100% is not mutagenic in the Salmonella typhimurium/Escherichia coli reverse mutation assay under the experimental conditions chosen here.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

A bacterial reverse gene mutation assay (DuPont 1976, equivalent to OECD guideline 471 with the limitation that no E.coli or TA102 strain was tested) is available. Bacteria strains of S. typhimurium TA 98, TA 1535, TA 1537, TA 1538 were exposed to cyclohexanol (no data on analytical purity) in ethanol at concentrations of 0, 500, 1000, 2500, 5000, 7500, 10000, 15000 μg/plate in the presence and absence of mammalian metabolic activation using the plate incorporation method. Cyclohexanol was tested up to the limit concentration of 5000 μg/plate and beyond. Cytotoxicity was seen at concentrations ≥7500 μg/plate. The positive controls induced the appropriate responses in the corresponding strains. There was no evidence of induced mutant colonies over background.

Justification for classification or non-classification

Classification, Labelling, and Packaging Regulation (EC) No. 1272/2008

The available experimental test data are reliable and suitable for classification purposes under Regulation 1272/2008. As a result the substance is not considered to be classified for mutagenicity under Regulation (EC) No. 1272/2008.