Corn oil (Zea mays, Gramineae), peroxidised

Endpoint summary

Additional information

The ability of peroxidised corn oil to induce genetic damage was assessed in three studies in vitro. All these studies performed according to OECD guidelines and in compliance with GLP, were scored as validity 1 or 2 according to Klimisch criteria and were thus considered as Key studies.

The Ames test, scored as validity 2 according to Klimisch criteria and then selected as Key study, was performed on the Sanyrene/Corpitol in order to evaluate the mutagenic potential of the test article. The study was conducted according to the requirements of the ISO 10993 standard: Biological evaluation of medical devices – Part 3: tests for genotoxicity, carcinogenicity and reproductive toxicity, and according to an adaptation of OECD Guideline n°471.

Extracts of the test article were prepared as follows:

- Extraction vehicles: 0.9% sodium chloride and 96% ethanol

- Duration: 72 +/- 2 hours with agitation

- Ratio test article/vehicle: 0.2 g/mL for the 0.9% NaCl extracts (study 1 & 2) and 96% ethanol extracts (study 1), 0.4 g/mL for the 96% ethanol extracts (study 2)

- Temperature: 37°C +/- 1°C

Suspensions of four strains of Salmonella typhimurium (TA98, TA100, TA1535, TA1537) and a strain of Escherichia coli WP2 uvrA were exposed to the test article extracted (up to 100%) in 0.9% NaCl and in 96% ethanol in the presence and in the absence of an exogenous metabolic activation system.

Under the conditions of this study, the test article extracted in 0.9% NaCl and 96% ethanol were not toxic and not mutagenic in the tested species. The extracts of the test article met the requirements of the test. The negative and positive controls performed as anticipated.

In a mammalian cell gene mutation assay (scored as validity 1 according to Klimisch criteria and then selected as Key study) at the hypoxanthineguanine phosphoribosyl transferase (hprt) locus, Chinese hamster lung V79 cells cultured in vitro were exposed to peroxidised corn oil in Tween 80 at concentrations of  0, 312.5, 625, 1250, 2500, 5000 µg/mL in the presence and absence of mammalian metabolic activation. 

Negative, vehicle and positive control treatments were included in each Mutation Experiment in the absence and presence of S-9. Mutant frequencies in negative and vehicle control were consistent with the acceptable range and clear increases in mutant frequency were observed by the positive controls, ethyl methanesulphonate (without S-9) and 7,12-dimethylbenz(a)anthracene (with S-9). The assay system was therefore considered to be both sensitive and valid.

In Experiment 1 both, in the absence of S-9 and in the presence of S-9, no statistically significant increases in mean mutant frequency were observed following treatment with Peroxidised corn oil at any concentration tested. The cytotoxic effect of test article was not observed in the whole concentration range of 312.5-5000 μg/mL.

In Experiment 2 both, in the absence of S-9 and in the presence of S-9, no statistically significant increases in mean mutant frequency were observed following treatment with Peroxidised corn oil at any concentration tested. The cytotoxic effect of test article was not observed in the whole concentration range of 312.5-5000 μg/mL.

It is concluded Peroxidised corn oil did not induce mutation at the hprt locus of V79 Chinese Hamster lung cells when tested under the conditions employed in this study.

In a mammalian cell cytogenetics assay (Chromosome aberration) according to OECD TG 473 and GLP (scored as validity 1 according to Klimisch criteria and then selected as Key study), V79 cell cultures were exposed to peroxidised corn oil in Tween 80 at concentrations of 0, 156.25, 312.5, 625, 1250, 2500, 5000 µg/mLwith and/or without metabolic activation.

 

Peroxidised corn oil was tested up to limit concentration and did not induce a statistically significant increase in the percentage of cells with aberrations (aberrant metaphases) both with and without metabolic activation when compared to the solvent controls, at the concentration tested. Positive controls induced the appropriate response. 

Therefore, under the conditions of the test and according to the criteria of evaluation, peroxidised corn oil was negative both with and without metabolic activation in the V79 chromosome aberration test.

 

No data is available on the genetic toxicity in vivo endpoint. As peroxidised corn oil was tested negative in vitro tests (Ames test, mammalian chromosome aberration test and mammalian gene mutation test), therefore no in vivo genetic toxicity assay should be performed in accordance with column 2 adaptation of REACH regulation Annex VIII, section 8.4.

Short description of key information:
No indication of genetic toxicity based on in vitro test results: Ames test, mammalian chromosome aberration test, and gene mutation assay in mammalian cells.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Based on the classification criteria of Annex VI Directive 67/548/CEE or UN/EU GHS, and considering the negative results in the three in vitro genetic toxicity tests using peroxidised corn oil, no classification for mutagenicity is required.