Fatty acids, C16-18, stearyl esters

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Genetic toxicity in vitro

Ames test (OECD 471, read across): negative with and without metabolic activation in S. typhimurium TA 1535, TA 1537, TA 100, TA 98, TA 102, E. coli WP2 uvrA, and E. coli WP2 uvrA pKM 101.

Chromosome aberration (OECD 473, read across): negative in Chinese hamster lung fibroblasts (V79) and in primary human peripheral lymphocytes with and without metabolic activation.

Gene mutation in mammalian cells (OECD 476, read across): negative in Chinese hamster lung fibroblasts (V79) with and without metabolic activation.

Link to relevant study records

Reference

Reference 1

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Remarks:

Summary of available data used for the endpoint assessment of the target substance

Adequacy of study:

weight of evidence

Justification for type of information:

refer to analogue justification provided in IUCLID section 13

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Key result

Species / strain:

other: TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Remarks on result:

other: Source: CAS 93803-87-3

The bacterial reverse mutation assay with the source substance 2-octyldodecyl isooctadecanoate (CAS 93803-87-3) was selected as key result for reasons of structural similarity and data reliability. Additional data on mutagenicity in bacteria (Ames test) is given for the source substance 2-octyldodecyl myristate (CAS 22766-83-2): no mutagenicity was found in S. typhimurium strains TA 1535, TA 1537, TA 98 and TA 100, and E. coli WP2 uvrA pKM 101 strains when tested at concentrations up to the limit value of 5 µL/plate with or without metabolic activation.

Conclusions:

The read across approach is justified in the analogue justification. The target and source substances are considered unlikely to differ in their bacterial mutagenicity potential. Bacterial reverse mutation assays have been performed with the two structural analogue source substances 2-octyldodecyl isooctadecanoate (CAS 93803-87-3) and 2-octyldodecyl myristate (CAS 22766-83-2) both in the presence as well as in the absence of metabolic activation. All results obtained were negative, i.e. no gene mutation in bacteria was observed. Therefore, no mutagenic potential in bacteria is expected for target substance Fatty acids, C16-18 (even numbered), stearyl esters (CAS 85536-04-5).

Reference 2

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Remarks:

Summary of available data used for the endpoint assessment of the target substance

Adequacy of study:

weight of evidence

Justification for type of information:

refer to analogue justification provided in IUCLID section 13

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Key result

Species / strain:

lymphocytes: cultured human peripheral lymphocytes

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Remarks on result:

other: Source: CAS 93803-87-3

An in vitro mammalian chromosome aberration test with the source substance 2-octyldodecyl isooctadecanoate (CAS 93803-87-3) was selected as key result for reasons of structural similarity and data reliability. Additional data on in vitro cytogenicity is given for the source substance oleyl oleate (CAS 3687-45-4). No increase in the frequency of cells with chromosome aberrations was found in Chinese hamster lung fibroblast (V79) cells when tested up to precipitating concentrations of 100 µg/mL in the presence and absence of metabolic activation. The adequacy of test was determined vehicle, negative and positive controls, which were found to be valid.

Conclusions:

The read across approach is justified in the analogue justification. The target and source substances are considered unlikely to differ in their genotoxic potential. In vitro mammalian cell chromosome aberration studies were performed with the source substances 2-octyldodecyl isooctadecanoate (CAS 93803-87-3) and oleyl oleate (CAS 3687-45-4) both in the presence and absence of metabolic activation. With both source substances no increase in the frequency of cells with chromosome aberrations was found in Chinese hamster lung fibroblast (V79) when tested up to precipitating concentrations. Therefore, no hazard with regard to chromosome aberration in mammalian cells is expected for target substance Fatty acids, C16-18 (even numbered), stearyl esters (CAS 85536-04-5).

Reference 3

Endpoint:

in vitro gene mutation study in mammalian cells

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Justification for type of information:

refer to analogue justification provided in IUCLID section 13

Reason / purpose for cross-reference:

read-across source

Key result

Species / strain:

Chinese hamster lung fibroblasts (V79)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Remarks:

precipitation at limit of water solubility at 100 µg/mL observed.

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: Source: CAS 3687-45-4

Conclusions:

The read across approach is justified in the analogue justification. The target and source substances are considered unlikely to differ in their genotoxic potential. An in vitro mammalian cell gene mutation study was performed with the source substance oleyl oleate (CAS 3687-45-4) both in the presence as well as in the absence of metabolic activation. No significant increase in mutation frequency was found in Chinese hamster lung fibroblast (V79) cells. Therefore, no mutagenic potential in mammalian cells is expected for target substance Fatty acids, C16-18 (even numbered), stearyl esters (CAS 85536-04-5).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Mode of Action Analysis / Human Relevance Framework

Not applicable

Additional information

Justification for read across

No data on the potential for genetic toxicity of Fatty acids, C16-18 (even numbered), stearyl esters (CAS 85536-04-5) are available. The assessment was therefore based on studies conducted with analogue substances as part of a read across approach, which is in accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.5. For each specific endpoint the source substance(s) structurally closest to the target substance is/are chosen for read-across, with due regard to the requirements of adequacy and reliability of the available data. Structural similarities and similarities in properties and/or activities of the source and target substance are the basis of read-across. A detailed justification for the analogue read-across approach is provided in the technical dossier (see IUCLID Section 13).

Genetic toxicity (mutagenicity) in bacteria in vitro

CAS 93803-87-3

The in vitro genetic toxicity of 2-octyldodecyl isooctadecanoate (CAS 93803-87-3) was assessed in a bacterial reverse mutation study (Ames test), performed under GLP conditions according to OECD guideline 471(WoE, 1998). S. typhimurium strains TA 1535, TA 1537, TA 98 and TA 100, and E. coli WP2 uvr A were exposed to the test substance at concentrations up to 1000 µg/plate. Precipitation was observed in the medium from 1000 µg/plate and above in all strain, with and without metabolic activation. The negative and positive controls were valid. The test substance did not induce reversions in the S. typhimurium strains or E. coli strain, with or without metabolic activation. Based on the study results, no mutagenicity in bacteria was found.

CAS 22766-83-2

The in vitro genetic toxicity of 2-octyldodecyl myristate (CAS 22766-83-2) was assessed in a bacterial reverse mutation study (Ames test), performed under GLP conditions according to OECD guideline 471 (WoE, 2007). The plate incorporation method was applied in the first experiment and the preincubation method in the second experiment, using S. typhimurium strains TA 1535, TA 1537, TA 98 and TA 100, and E. coli WP2 uvrA pKM 101. All the strains were tested at concentrations up to the limit value of 5 µL/plate. The test substance did not induce an increase in reversions in the S. typhimurium and E.coli strains, with or without metabolic activation. No bacterial mutagenicity was observed, with and without metabolic activation. The positive and vehicle controls were valid. Based on the study results, no mutagenicity in bacteria was found.

Genetic toxicity (mutagenicity) in mammalian cells in vitro

CAS 3687-45-4

An in vitro mammalian cell gene mutation study was performed with oleyl oleate (CAS 3687-45-4) under GLP conditions according to OECD guideline 476 (key study, 1994). Two separate experiments were performed. Chinese hamster lung fibroblast (V79) cells were treated with oleyl oleate at concentrations of up to 100 µg/mL for 4 hours, with and without metabolic activation. After an expression time of 7 days in growth medium, cells were incubated for 9 or 12 days with 6 -thioguanine as selection agent for forward mutation at the HPRT locus. Precipitation was seen at concentrations of 100 µg/mL and higher, while no cytotoxicity was observed at any concentration level. The positive and negative controls were valid and within the range of historical control data. No significant increase in mutation frequency was observed, with and without metabolic activation. Based on the study results, no mutagenicity in mammalian cells was found.

Genetic toxicity (cytogenicity) in mammalian cells in vitro

CAS 3687-45-4

The potential of oleyl oleate (CAS 3687-45-4) to induce chromosomal aberrations was assessed using Chinese hamster lung fibroblast (V79) cells, in a GLP study performed according to OECD 473 (WoE, 1994). The V79-cells were exposed to oleyl oleate at concentrations up to 100 µg/mL, with and without metabolic activation (S9-mix). One experiment with duplicate replications was performed. A 4-hour treatment was performed without metabolic activation, using 10, 60 and 100 µg/mL concentration levels with 18-hour fixation time and a 100 µg/mL concentration level with a 28-hour fixation time. The treatment with metabolic activation was performed at concentrations of 10, 60 and 100 µg/mL with an 18-hour treatment time, and 18-hour fixation time and at 100 µg/mL with a 28-hour treatment time and 28-hour fixation time, respectively. The test material did not induce a statistically significant increase in the frequency of cells with chromosome aberrations, with or without metabolic activation. Precipitation was observed at concentrations from 100 µg/mL, while no cytotoxicity was noted at any concentration. The negative and positive controls were valid.

CAS 93803-87-3

The cytogenicity potential of 2-octyldodecyl isooctadecanoate (CAS 93803-87-3) was assessed in an in vitro mammalian chromosome aberration test in primary human lymphocytes, performed according to OECD Guideline 473 and under GLP conditions (WoE, 1998). Duplicate cultures of cultured human peripheral lymphocytes were evaluated for chromosome aberrations in the presence and absence of metabolic activation. In the first experiment, cells were incubated with test substance concentrations of 100, 333 and 1000 µg/mL for 24 hours with a 24-hour fixation time and at 1000 µg/mL for 48 hours with a 48-hour fixation time, in the absence of a metabolic activation system. The first experiment was also performed with cells exposed to 100, 333 and 1000 µg/mL for 3 hours with a 24-hour fixation time and at 1000 µg/mL for 3 hours with a 48-hour fixation time in the presence of metabolic activation. In the second experiment cells were incubated with 100, 333 and 1000 µg/mL for 24 hours followed by a 24-hour expression time, without metabolic activation. In the presence of metabolic activation cell were exposed to 100, 333 and 1000 µg/mL for 3 hours followed by a 24-hour expression time. No cytotoxicity was observed. At 1000 µg/mL, precipitation was observed in the culture medium. The vehicle and positive controls were valid. The test material did not induce a statistically significant increase in the frequency of cells with chromosome aberrations, with or without metabolic activation.

Overall conclusion for genetic toxicity

There are no available studies on the genetic toxicity of the target substance Fatty acids, C16-18 (even numbered), stearyl esters (CAS 85536-04-5).Therefore analogue read-across from source substances was applied from in vitro studies on cytogenicity, and in vitro studies on gene mutation in bacterial cells and mammalian cells. The results of the available in vitro studies were consistently negative. Based on the available data and following the analogue approach, no mutagenic or clastogenic potential in vitro is expected for Fatty acids, C16-18 (even numbered), stearyl esters (CAS 85536-04-5).

Justification for classification or non-classification

According to Article 13 of Regulation (EC) No. 1907/2006 "General Requirements for Generation of Information on Intrinsic Properties of substances", information on intrinsic properties of substances may be generated by means other than tests e.g. from information from structurally related substances (grouping or read-across), provided that conditions set out in Annex XI are met. Annex XI, "General rules for adaptation of this standard testing regime set out in Annexes VII to X” states that “substances whose physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity may be considered as a group, or ‘category’ of substances. This avoids the need to test every substance for every endpoint". Since the analogue concept is applied to Fatty acids, C16-18 (even numbered), stearyl esters (CAS 85536-04-5), data will be generated from data for reference source substance(s) to avoid unnecessary animal testing. Additionally, once the analogue read-across concept is applied, substances will be classified and labelled on this basis.

Therefore, based on the analogue read-across approach, the available data on genetic toxicity do not meet the classification criteria according to Regulation (EC) 1272/2008 and are therefore conclusive but not sufficient for classification.