Glycerides, C16-18

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Description of key information

In vitro

 

A study was conducted to determine the mutagenicity potential of ‘glycerides, C8 -18 and C18 -unsatd.’ (as coconut oil) according to an unspecified method. Under the study conditions, the substance was found to be non-mutagenic in Salmonella typhimurium reverse mutation assay at a concentration of 5,000 μg/plate (Biotech Index, 1970).

 

A study was conducted to determine the mutagenicity potential of ‘glycerides, C8 -18 and C18 -unsatd.’ (as coconut oil) in a bacterial reverse mutation assay using Salmonella typhimurium strains. The substance was tested at concentrations of 50, 150, 500, 1,500 and 5,000 μg/plate with Salmonella typhimurium TA 1535, TA 1537, TA 98 and TA 100. Under the study conditions, the substance was found to be non-mutagenic in the Salmonella typhimurium gene mutation assay (IUCLID DS, 2000).

 

A study was performed to investigate the potential mutagenicity of ‘glycerides, C16 and C18-unsatd. and C18-unsatd. hydroxy’ (as castor oil) through the reverse mutation assay using Salmonella typhimurium strains TA 1535, TA 97, TA 98 and TA 100, along with Aroclor-induced 10 and 30% liver fraction for metabolic activation (S9-mix). Salmonella strains were exposed to five different concentrations (0, 100, 333, 1,000, 3,333 and 10,000 μg/plate) of the substance and vehicle control (DMSO), in both absence and the presence of S9-mix. Three parallel plates were used for each dose. Concurrent positive controls, 2-aminoanthracene (for all strains, with metabolic activation), 4-nitro-ophenylenediamine (on TA 98, without metabolic activation), sodium azide (TA100 and TA1535) and 9-aminoacridine (TA97) were also included in the assays. In both absence and presence of the S9-mix, the substance did not cause a significant increase in the number of revertant colonies in comparison to the control. Both positive and vehicle control groups were also valid. Hence, under the test conditions, the substance was considered to be non-mutagenic in Salmonella typhimurium mutation assay (Irwin, 1992).

 

A study was performed to investigate the genotoxic potential of ‘glycerides, C16 -18 and C18-unsatd.’ (as castor oil) to induce chromosomal aberrations in Chinese hamster ovary cells. Chinese hamster ovary cells were incubated with 0, 1,600, 3,000 and 5,000 μg/mL of the substance or solvent (DMSO). Cells were arrested in first metaphase by addition of colcemid and harvested by mitotic shake off, fixed, and stained in 6% Giemsa. Where relevant S9 was from the livers of Aroclor 1254-induced male Sprague Dawley rats was added. No significant chromosome aberrations were observed when treated with concentrations up to 5,000 μg/mL of the substance with and without S9. Hence, under the test conditions, the substance was considered to be non-genotoxic to Chinese hamster ovary cells in chromosomal aberration assay (Irwin, 1992).

 

A study was conducted to determine the potential mutagenicity of ‘glycerides, C16-18 and C18 -unsatd.’ (as pine nut oil) according to the OECD guideline 471. Salmonella typhimurium strains TA1535, TA1537, TA98 and TA100 and Escherichia coli strain WP2uvrA- were treated with the substance using the Ames plate incorporation method at five dose levels, in triplicate, both with and without the addition of a rat liver homogenate metabolising system (10% liver S9 in standard cofactors). The dose range was determined in a preliminary toxicity assay and was 3 to 5,000 μg/plate. The experiment was repeated using the same dose range as the range-finding test. The substance precipitated at the two highest concentrations tested and therefore it was tested up to the third dose level of 1,000 μg/plate. No precipitate was observed on the plates at any of the doses tested in either the presence or absence of S9 -mix. No significant increases in the frequency of revertant colonies were recorded for any of the bacterial strains, with any dose of the substance, either with or without metabolic activation. Under the conditions of this test, the substance was considered to be non-mutagenic (Speijers, 2009).

 

A study was performed to investigate the genotoxic potential of ‘glycerides, C16 -18 and C18 -unsatd.’ (as castor oil) to induce sister-chromatid exchanges in Chinese hamster ovary cells. Chinese hamster ovary cells were incubated with 160, 500, 1,600 and 5,000 μg/mL of the substance or solvent (DMSO). Cells were then collected by mitotic shake-off, fixed, air-dried and stained. Where relevant S9 was from the livers of Aroclor 1254-induced male Sprague Dawley rats was added. No significant sister-chromatid exchange was observed in Chinese hamster ovary cells treated with concentrations up to 5,000 μg/mL of the substance with and without S9. Hence, under the test conditions, the substance was considered to be non-genotoxic to Chinese hamster ovary cells in sister-chromatid exchange assay (Irwin, 1992).

 

A study was conducted to determine the mutagenic potential of ‘glycerides, C16 -18 and C18 -unsatd.’ (as palm oil) according to OECD guideline 471. Salmonella typhimurium strains TA1535, TA1537, TA98 and TA100 were treated with the substance using the Ames plate incorporation method at five dose levels (up to 5,000 μg/plate), with and without metabolic activation. Two independent assays were conducted. Under the conditions of the study, the substance was considered to be non-mutagenic (IUCLID DS, 2000).

A study was conducted to determine the potential for gene mutation in mammalian cells according to a method equivalent to OECD Guideline 476. Ethyl methane sulfonate and 3-methylcholanthrene served as the positve control. Positive controls gave the expected results, validating the assay. Corn oil did not alter either the relative cloning efficiency or the mutation frequency of the cells. Under the study conditions, corn oil did not show any evidence of HPRT gene mutation in CHO cells (Hayes et al, 1994; ECHA, 2021).

In vivo

 

A study was conducted to evaluate if ‘glycerides, C16-18 and C18-unsatd.’ (as palm oil) have any clastogenic effects in Balb/c mice. 10 mice were used per group. The exposure period lasted 5 d and the dose was 4500 mg/kg bw. Analyses were made on bone marrow metaphase cells isolated 24 h post application for chromosome abberations and mitotic index. The study showed no statistically significant difference in the frequency of chromosomal abberations and mitotic index between either of the treated groups and the control group. Under the conditions of the test, the substance did not show any clastogenic effects in mice bone marrow cells (IUCLID, 2000).

 

A study was performed to investigate the genotoxic potential of ‘glycerides, C16 and C18-unsatd. and C18 -unsatd. hydroxy’ (as castor oil) to induce micronuclei in polychromatic erythrocytes (PCE) in the peripheral blood of the mouse. Groups of 10 mice/sex were exposed to 0, 0.6, 1.3, 2.5, 5.0 and 10.0% concentrations of the substance mixed in diet for 13 weeks. At termination, smears were prepared from peripheral blood samples obtained by cardiac puncture of dosed and control animals. Slides were stained with Hoechst 33258/pyronin Y. About 2,000 PCE and 10,000 NCE from each animal were scored for frequency of micronuclei. No significant elevation in the frequency of micronucleated erythrocytes was observed in either male or female mice administered test substance in dosed feed. Therefore, under the test conditions, the substance was considered to be non-genotoxic in the micronucleus test in B6C3F1 mice (Irwin, 1992).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Justification for classification or non-classification

The weight of evidence from structurally similar substances of the same read-across category suggests that ‘glycerides, C16-18 (SDA Reporting Number: 19-001-00)’ are unlikely to exhibit genotoxic activity in bacterial reverse mutation (Ames) assays, in vitro mammalian chromosome aberration tests with Chinese hamster ovary cells, in vitro gene mutation assay in CHO cells and/or an in vivo mouse micronucleus or chromosomal aberration assay. Further, predictions from the Danish QSAR database and Toxtree (v.1.6) did not reveal any evidence for genotoxic activity in either in vitro bacterial or mammalian cell systems or in vivo test systems. The above evidence, added to the very long history of safe use of these substances in nutritional (food and feed), cosmetic and industrial uses, suggests that ‘glycerides, C16-18 (SDA Reporting Number: 19-001-00)’ is unlikely to not have a mutagenic potential. Based on the above information, therefore the substance does not qualify for mutagenicity classification according to EU CLP Regulation (EC) 1272/2008.