Lauric acid, ester with hydroxypropanediyl diacetate

Endpoint summary

Additional information

Analogue justification

No data on the in vitro genetic toxicity in bacterial and mammalian cells of Lauric acid ester with hydroxypropanediyl diacetate (CAS 30899-62-8) are available. The genetic toxicity 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 read across approach is provided in the technical dossier (see IUCLID Section 13).

Genetic toxicity (mutagenicity) in bacteria in vitro

CAS 91031-52-0

A bacterial gene mutation assay with Glycerides, C8-18 and C18-unsatd. mono- and di-, acetates was performed according to OECD guideline 471 and under GLP conditions (Sarada, 2010). Two independent experiments were performed both in the presence or absence of metabolic activation in S. typhimurium TA 1535, TA 1537, TA 98 and TA 100 and in E. coli WP2 uvrA. In the preliminary toxicity screening, growth inhibitory effects were observed at ≥ 20 µg/plate in S. typhimurium TA 98 and TA 1537 (without metabolic activation), at ≥ 78 µg/plate in S. typhimurium TA 100 and TA 1535 (without metabolic activation), and at ≥ 313 µg/plate in all S. typhimurium strains with metabolic activation. Based on these results, the tester strains TA 100, TA 1535, TA 98 and TA 1537 were exposed to concentrations of 10 - 313 µg/plate in the presence of metabolic activation, and to concentrations from 0.61 to 78 µg/plate in the absence of metabolic activation. Since no cytotoxicity was seen in E. coli WP2 uvrA, the maximum test concentration of 5000 µg/plate and concentrations of 2500, 1250, 625 and313 µg/plate were selected for treatment in the main assay. Precipitation of the test substance was observed on the plates with E. coli WP2 uvrA at test concentrations ≥ 1250 µg/plate without metabolic activation and at ≥ 2500 µg/plate with metabolic activation in both experiments. No increase in mean revertant number was observed in any bacterial strain after exposure to the test substance in the presence or absence of metabolic activation. The positive and negative controls revealed the expected results. Under the conditions of this assay, the test substance did not induce gene mutations in the selected strains of S. typhimurium and in E. coli WP2 uvrA in the absence and presence of metabolic activation.

CAS 736150-63-3

The potential mutagenicity of Glycerides, castor-oil mono, hydrogenated, acetates was assessed in a bacterial mutation assay according to OECD guideline 471 and in compliance with GLP (Edwards, 2004). S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102 were exposed to concentrations of 50 - 5000 µg/plate with or without S9-mix in two independent experiments. No dose-dependent increase in the mean number of revertants per plate was observed in any tester strain up to the maximum exposure concentration. Slight cytotoxicity, as indicated by a small reduction in the number of revertants compared to controls, was induced in TA 100 at 5000 µg/plate (with metabolic activation) in the preincubation assay (experiment I) and in TA 1535 at 160 µg, 1600 µg and 5000 µg/plate (with metabolic activation) in the plate incorporation assay (experiment II). The solvent and positive control values were within the historical control values. Based on the results of this study, the test substance did not induce mutagenicity in the selected strains of S. typhimurium in the presence and absence of metabolic activation.

Genetic toxicity (cytogenicity) in mammalian cells in vitro

CAS 91052-13-0

An in vitro mammalian chromosome aberration test with was performed in Chinese hamster lung cells (CHL/IU) with Glycerides, C8 -18 and C18-unsatd. mono- and di-, acetates, according to OECD guideline 473 and under GLP conditions (Seki, 2010). In a preliminary cell growth inhibition test with concentrations ranging from 9.8 to 5000 µg/plate, no significant inhibition of cell growth was observed after 4 h exposure in the presence and absence of metabolic activation (S9 mix). However, a moderate reduction of cell growth of 30-40% compared with the controls was observed at concentrations ranging from 156-1250 µg/mL after 24 and 48 h continuous exposure. Based on the results of this study, concentrations of 20, 39, 78 and 156 µg/mL (with and without metabolic activation) were used for the analysis of chromosomal aberrations after short-term exposure (6 h). In addition, concentrations of 78, 156, 313, 625, 1250, 2500 and 5000 µg/mL were chosen for analysis chromosomal aberrations after continuous exposure (24 and 48 h), without metabolic activation. No increase in the number of cells with chromosomal aberrations was observed compared to controls in any of the experiments performed. No cytotoxic effects were observed in any of the experiments performed. An oily precipitation of the test substance was observed at concentrations ≥ 78 µg/mL, but did not interfere with chromosomal analysis of the cells. The positive controls included during short-term and continuous exposure were shown to be valid. Under the conditions of this experiment, the test substance was considered to be not clastogenic in Chinese hamster lung cells (CHL/IU), in the presence and absence of metabolic activation.

Genetic toxicity (mutagenicity) in mammalian cells in vitro

CAS 736150-63-3

An in vitro mammalian cell gene mutation assay was performed with Glycerides, castor-oil mono, hydrogenated, acetates according to OECD guideline 476 and under GLP conditions (Edwards, 2002). In the first experiment, mutations at the TK locus of mouse lymphoma L5178Y cells were investigated at concentrations of 625, 1250, 2500, 3600 and 5000 µg/mL. The L5178Y cells were exposed to the test material for 3 h in the presence and for 4 h in the absence of metabolic activation (S9-mix), respectively. At 3600 µg/mL, the relative total growth was 1-11% compared with the negative controls. In the second experiment, cells were exposed to a concentration range of 313 - 3600 µg/mL for a period of 24 h without metabolic activation, and to a concentration range of 156 - 3600 µg/mL for a period of 4 h with metabolic activation. Since the relative growth without metabolic activation was very low (0-2%) at all test concentrations, the 24-h treatment of cells in the absence of metabolic activation was repeated with concentrations ranging from 2.5 - 320 µg/mL, which resulted in 10-20% relative growth at 160 µg/mL. In the presence of metabolic activation, the relative total growth was 37 and 0% at 2500 and 3600 µg/mL in the second experiment, respectively. After a 3-day expression period of the cultures, the resistance to 5-trifluorothymidine (TFT) was determined in all experiments. The test substance did not induce a significant increase in the mutant frequency at any preparation time and dose concentration. The positive controls significantly increased mutant frequency. The test substance did not induce mutations in mouse-lymphoma L5178Y cells in the presence or in the absence of a metabolic activation system.

Overall conclusion for genetic toxicity

There are no available studies on the genetic toxicity of Lauric acid ester with hydroxypropanediyl diacetate (CAS 30899-62 -8) in bacterial and mammalian cells. Analogue read-across from 2 source substances was applied fromin vitro studies in bacterial cells, and from in vitro studies on cytogenicity and gene mutations in mammalian cells. The results of the available in vitro studies were consistently negative. Based on the available data and following the analogue approach, Lauric acid ester with hydroxypropanediyl diacetate (CAS 30899-62-8) is not expected to be mutagenic in vitro and clastogenic in vitro.

Justification for selection of genetic toxicity endpoint
Hazard assessment is conducted by means of read-across from structural analogues. All available in vitro genetic toxicity studies were negative. All available studies are adequate and reliable based on the identified similarities in structure and intrinsic properties between source and target substances and overall quality assessment (refer to the endpoint discussion for further details).

Short description of key information:
Ames test (OECD 471): negative with and without metabolic activation in S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102, and in E. coli WP2 uvrA pKM
Chromosome aberration (OECD 473): negative in Chinese hamster lung cells (CHL/IU) with and without metabolic activation
Gene mutation in mammalian cells (OECD 476): negative in mouse lymphoma L5178Y cells with and without metabolic activation

Endpoint Conclusion: No adverse effect observed (negative)

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 Lauric acid ester with hydroxypropanediyl diacetate (CAS 30899-62-8), data will be generated from 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.