Sodium long chain alkyl salicylate

Endpoint summary

Additional information

In vitro

Three key studies are available to address the in vitro genetic toxicity of the test material. All were awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

The mutagenic activity of the test material was evaluated in a bacterial reverse mutation assay conducted in accordance with the standardised guidelines OECD 471 and EU Method B.13/14 under GLP conditions.

The test material was tested with four histidine-requiring strains of Salmonella typhimurium (TA1535, TA1537, TA98 and TA100) and with a tryptophan-requiring strain of Escherichia coli (WP2uvrA). The test was performed in two independent experiments in the presence and absence of S9-mix (rat liver S9-mix induced by Aroclor 1254).

In the dose range finding test, the test material was tested up to concentrations of 5000 µg/plate in the absence and presence of S9-mix in the strains TA100 and WP2uvrA. The test material did not precipitate on the plates at this dose level. In the tester strain TA100, toxicity was observed at dose levels of 512 µg/plate and above in the absence of S9-mix and at 5000 µg/plate in the presence of S9-mix. In the tester strain WP2uvrA, no toxicity was observed at any of the dose levels tested.

Based on the results of the dose range finding test, the test material was tested in the first mutation assay at a concentration range of 5.4 to 1600 µg/plate in the absence of S9-mix and at 52 to 5000 µg/plate in the presence of 5 % (v/v) S9-mix in tester strains TA1535, TA1537 and TA98. Toxicity was observed in all three tester strains.

In the second mutation assay, the test material was tested up to concentrations of 1600 µg/plate in the absence of S9-mix in tester strains TA1535, TA1537, TA98 and TA100 and up to 3330 µg/plate (TA1537) and 5000 µg/plate (TA1535, TA98, TA100) in the presence of 10 % (v/v) S9-mix. The test material was tested up to concentrations of 5000 µg/plate in the absence and presence of S9-mix in the tester strain WP2uvrA. Toxicity was observed in all tester strains, except in the tester strain WP2uvrA in both the absence and presence of S9-mix and in the tester strain TA1535 in the presence of S9-mix.

The test material did not induce a significant dose-related increase in the number of revertant (His+) colonies in each of the four Salmonella tester strains and in the number of revertant (Trp+) colonies in the Escherichia tester strain both in the absence and presence of S9-metabolic activation. These results were confirmed in a follow-up experiment.

In this study, the negative and strain-specific positive control values were within the laboratory historical control data ranges indicating that the test conditions were adequate and that the metabolic activation system functioned properly.

Under the conditions of this study, the test material was determined to be non-mutagenic in both the presence and absence of metabolic activation.

The ability of the test material to induce chromosome aberrations in cultured peripheral human lymphocytes was evaluated in a study conducted in accordance with the standardised guidelines OECD 473 and EU Method B.10 under GLP conditions.

The study investigates the effect of the test material on the number of chromosome aberrations in cultured peripheral human lymphocytes in the presence and absence of a metabolic activation system (phenobarbital and ß-naphthoflavone induced rat liver S9-mix). The possible clastogenicity of the test material was tested in two independent experiments.

Experiments were carried out in duplicate and concurrent solvent (ethanol) and positive controls took place.

In the first cytogenetic assay, the test material was tested up to 200 µg/mL for a 3 hour exposure time with a 24 hour fixation time in the absence and presence of 1.8 % (v/v) S9-fraction. Appropriate toxicity was reached at this dose level.

In the second cytogenetic assay, the test material was tested up to 45 µg/mL for a 24 hour continuous exposure time with a 24 hour fixation time and up to 40 µg/mL for a 48 hour continuous exposure time with a 48 hour fixation time in the absence of S9-mix. Appropriate toxicity was reached at these dose levels.

The number of cells with chromosome aberrations found in the solvent control cultures was within the laboratory historical control data range. The positive controls produced a statistically significant increase in the incidence of cells with chromosome aberrations, indicating that the test conditions were adequate and that the metabolic activation system (S9-mix) functioned properly.

The test material did not induce any statistically significant or biologically relevant increase in the number of cells with chromosome aberrations in the absence and presence of S9-mix, in either of the two independently performed experiments. It was concluded that the test was valid.

No effects of the test material on the number of cells with endoreduplicated chromosomes were observed both in the absence and presence of S9-mix. Therefore it can be concluded that the test material does not disturb cell cycle progression under these experimental conditions.

However, it was noted that the test material increased the number of polyploid cells both in the absence and presence of S9-mix at the 3 hour exposure at the highest concentration tested. This may indicate that the test material has the potential to disturb mitotic processes.

Under the conditions of this study the test material is not clastogenic in human lymphocytes with and without metabolic activation. The test material may have the potential to disturb mitotic processes although the significance is not clear.

The mutagenic activity of the test material was evaluated in an in vitro mammalian cell gene mutation test with L5178Y mouse lymphoma cells. The study was conducted in accordance with the standardised guidelines OECD 476 and EU Method B.17 under GLP conditions.

The study investigated the effects of the test material on the induction of forward mutations at the thymidine-kinase locus (TK-locus) in L5178Y mouse lymphoma cells. The test was performed in the absence of S9-mix with 3- and 24-hour treatment periods and in the presence of S9-mix with a 3 hour treatment period (rat liver S9-mix induced by a combination of phenobarbital and ß-naphthoflavone). Concurrent solvent (ethanol) and positive controls took place.

In the first experiment, the test material was tested up to concentrations of 35 and 60 µg/mL in the absence and presence S9-mix, respectively. The incubation time was 3 hours. Relative total growth (RTG) was reduced to 45 and 21 % in the absence and presence of S9-mix, respectively.

In the second experiment, the test material was tested up to a concentration of 30 µg/mL in the absence of S9-mix. The incubation time was 24 hours. The RTG was reduced to 13 %.

The spontaneous mutation frequencies in the solvent-treated control cultures were within the historical control data range and fulfilled the acceptability criteria of this assay.

Mutation frequencies in cultures treated with positive control chemicals were increased by 14- and 9.1-fold for methyl methanesulfonate in the absence of S9-mix, and by 12-fold for cyclophosphamide in the presence of S9-mix. In addition the observed mutation frequencies of the positive control materials fulfilled the acceptability criteria of this assay. It was therefore concluded that the test conditions, both in the absence and presence of S9-mix, were appropriate and that the metabolic activation system (S9-mix) functioned properly.

Under the conditions of this study the test material is not mutagenic in the presence and absence of metabolic activation.

Justification for selection of genetic toxicity endpoint
No single key study was selected on the basis that the available studies all address different aspects of genetic toxicity and the data should be considered as a whole. All three studies were conducted in accordance with standardised guidelines under GLP conditions.

Short description of key information:
IN VITRO
- Non mutagenic with and without metabolic activation (Ames test); OECD 471 and EU Method B.13/14
- Non clastogenic with and without metabolic activation (chromosome aberration test); OECD 473 and EU Method B.10
- Non mutagenic with and without metabolic activation (mouse lymphoma assay); OECD 476 and EU Method B.17

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

In accordance with the criteria for classification as defined in Annex I, Regulation (EC) No. 1272/2008, the substance does not require classification with respect to genetic toxicity.