2-Oxetanone, 3-C12-16-alkyl-4-C13-17-alkylidene derivs., (4E)-

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Ames test (OECDTG471): not mutagenic
Chromosome aberration test(OECDTG473): not clastogenic
Mouse lymphoma test (OECDTG490): not mutagenic

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Description of key information

Mammalian Erythrocyte Micronucleus Test (OECD Guideline 474): not clastogenic

Additional information

Conclusions of the studies performed with the source substance solid AKD:

In an Ames test the substance was tested for induction of gene mutations in S. typhimurium; TA98, TA100, TA1535, and TA1537, and E. coli strain WP₂uvrA in the presence or absence of an exogenous mammalian metabolic activation system (S9). Incidental cytotoxicity was observed characterized as a reduction of the number of revertants below the historical control range. Precipitation was observed at concentrations between 52 and 512 µg/plate. In two independent tests (test 1 plate incorporation; test 2 pre-incubation) no increase of the number of revertants compared to the vehicle (hexane) controls was observed at any of the concentrations evaluated. Therefore it is concluded that the substance is not mutagenic in bacteria.

 

The study wasperformed according to internationally accepted guidelines and under GLP. Aquapel^® 364 was evaluated for its clastogenic potential in an in vitro cytogenetic assay using human lymphocytes in two separate experiments treated in the presence and absence of a rat liver-derived metabolic activation system (S9-mix). In Experiment 1 cultures were treated for a period of 3 hours both in the presence and absence of S9-mix. In Experiment 2 cultures were treated for a period of 3 hours in the presence of S9 -mix and 20 hours in the absence of S9-mix. Cultures were harvested 68 hours after culture initiation. Cultures treated with Aquapel^® 364 at the following concentrations were selected for chromosomal aberration analysis along with the appropriate solvent and positive control cultures: 1000, 500, 100 µg/ml.

The highest concentration selected for chromosomal aberration analysis was limited by the solubility of the test substance in the culture medium. Concentrations above 1000 µg/ml were considered not to be suitable for analysis due to precipitated test substance present on the slides obscuring the metaphases or too few metaphases for analysis. No statistically or biologically significant increases in the percentage of aberrant cells, compared to the solvent control values, were recorded in cultures from either experiment treated in either the presence or absence of S9-mix. The sensitivity of the test system, and the metabolic activity of the S9-mix employed, were clearly demonstrated by the increases in the percentage of aberrant cells induced by the positive control agents, mitomycin C and cyclophosphamide.

It is concluded that, under the conditions of this assay, Aquapel^® 364 is not clastogenic to cultured human lymphocytes treated in vitro in either the presence or absence of S9-mix.

 

The substance was tested for its ability to induce forward mutations at the thymidine kinase (TK) locus in L5178Y mouse lymphoma cells, either in the absence or presence of a metabolic system (S9-mix) according to the procedures as described in OECD 490.

In the first experiment, the test item was tested up to concentrations of 35 µg/mL in the absence and presence S9-mix. The incubation time was 3 hours. No toxicity was observed at this dose level in the absence and presence of S9-mix.

The test item precipitated in the culture medium at this dose level.

In the second experiment, the test item was tested up to concentrations of 8 µg/mL in the absence of S9-mix. The incubation time was 24 hours. No toxicity was observed at this dose level. The test item precipitated in the culture medium at this dose level.

The mutation frequency found in the solvent control cultures was within the acceptability criteria of this assay and within the 95% control limits of the distribution of the historical negative control database.

In the absence of S9-mix, the test item did not induce a biologically relevant increase in the mutation frequency in the first experiment. This result was confirmed in an independent experiment with modification in the duration of treatment.

In the presence of S9-mix, the test item did not induce a biologically relevant increase in the mutation frequency.

In conclusion, the substance is not mutagenic in the mouse lymphoma L5178Y test system.

 

 

This study was designed to assess the potential induction of micronuclei by P-2290 in bone marrow cells of mice. Mice were treated with a single intraperitoneal administration of the test substance at dose levels of 500, 1000 and 2000 mg/kg bodyweight. A preliminary toxicity test had previously

shown that a dose of 2000 mg/kg was expected to be approximately the maximum tolerated and standard limit; this level was therefore selected as an appropriate maximum for use in the micronucleus test.

The test substance and negative control were administered by intraperitoneal injection. The negative control group received the vehicle, corn oil. A positive control group was dosed orally, by intragastric gavage, with mitomycin C at 12 mg/kg bodyweight. Bone marrow smears were obtained from five male and five female animals in the negative control, each of the test substance groups and the positive control group 24 hours after dosing. In addition bone marrow smears were obtained from five male and five female animals in the negative control and high level treatment groups 48 hours after dosing. One smear from each animal was examined for the presence of micronuclei in 2000 immature erythrocytes. The proportion of immature

erythrocytes was assessed by examination of at least 1000 erythrocytes from each animal. A record of the incidence of micronucleated mature erythrocytes was also kept. Mice treated with the test substance did not show any significant increase in the frequency of micronucleated immature erythrocytes at either sampling time. There was no significant decrease in the proportion of immature erythrocytes after treatment of the animals with the test substance. No statistically significant increases in the frequency of micronucleated immature erythrocytes or any substantial decrease in the proportion of immature erythrocytes were observed in mice treated with P-2290 and killed 24 or 48 hours later, compared to vehicle control values (p>0.01 in each case). The positive control compound, mitomycin C, produced large, highly significant increases in the frequency of micronucleated immature erythrocytes and a highly significant decrease in the proportion of immature erythrocytes (p<0.001 in each case). It is concluded that P-2290 did not show any evidence of causing chromosome damage or bone marrow cell toxicity when administered by intraperitoneal injection in this in vivo test procedure.

 

Executive summaries of the studies performed with the source substance behenic AKD:

 

It is concluded that, under the conditions of this assay, PMC D-532 gave a negative, i.e. non-mutagenic, response in S. typhimurium strains TA1535, TA1537, TA98 and TA100 and E coli strain WP2 uvrA (pKM101) in both the presence and absence of S9-mix.

 

It is concluded that, under the conditions of this assay, PMC D-532 is not clastogenic to cultured human lymphocytes treated in vitro in either the presence or absence of S9-mix.

 

 

The test material did not induce significant or dose-related increases in mutant frequency per survivor in either the presence of absence of metabolic activation in either of the two experiments. The test material was therefore considered to be non-mutagenic to CHO cells at the HPRT locus uder the conditions of this test.

 

Under the conditions of test, PMC D-532 is not clastogenic in the mouse bone marrow micronucleus test.

Justification for classification or non-classification

Based on the results of in vitro studies and in vivo studies with the source substances, the substance does not have to be classified for genotoxicity in accordance with Regulation (EC) No 1272/2008 and its amendments.