Ethyl 3,5-dichloro-4-hexadecyloxycarbonyloxybenzoate

Endpoint summary

Additional information

The mutagenic potential of ethyl 3,5-dichloro-4- hexadecyloxycarbonyloxybenzoate (AF-366) was assessed in three in vitro tests.

A bacterial reverse mutation assay (Ames test) was performed similar to OECD 471 (Wilmer, 1989a). The plate incorporation method was applied using S. typhimurium strains TA 1535, TA 1537, TA 1538, TA 98 and TA 100 at concentrations up to the limit value of 5000 µg/plate with and without metabolic activation. The test substance did not induce mutations in any of the tested strains with or without metabolic activation. No cytotoxic effects were observed up to and including the limit value of 5000 μg/plate. Precipitation was noted from 1666.7 µg/mL, with and without metabolic activation. The positive controls were shown to be valid.

The potential of AF-366 to induce chromosomal aberrations was tested in an assay with Chinese hamster ovary (CHO) cells according to OECD 473 (Wilmer, 1989b). CHO cells were exposed to the test substance at concentrations up to 250 µg/mL, as the test substance was shown in a solubility test to precipitate at a concentration of 500 µg/mL in cell culture medium. A short-term treatment (3 hours) was performed with a 12- and 21-hour harvest time, in the presence of metabolic activation. In addition, a 21-hour treatment with 21-hour harvest time without metabolic activation was performed. There were no increases in the number of chromosome aberrations at any dose level. No cytotoxic effects were observed and the positive controls induced a significant increase in the number of chromosomal aberrations.

In a mammalian cell gene mutation test performed according to OECD 476, Chinese hamster lung fibroblasts (V79) were exposed to AF-366 (Bednáriková, 2010). In two independent experiments, V79 cells were exposed to concentrations from 62.5 -1000 µg/mL.The highest concentration was selected based on the results of a range-finding study, in which the test substance precipitated in the culture medium from 2000 µg/mL with metabolic activation. The test substance did not cause an increase in gene mutation levels, with or without metabolic activation. There was no cytotoxicity up to and including the highest dose level of 1000 µg/mL and the positive controls induced significant increases in mutation frequency.  

Short description of key information:
In vitro:
Bacterial reverse mutation assay, Ames test (similar to OECD 471): negative
Mammalian cytogenetic test, chromosome aberrations, CHO (OECD 473): negative
Mammalian cell gene mutation test, Chinese hamster lung fibroblasts (V79) (OECD 476): negative

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

The available data on genetic toxicity of the test substance do not meet the criteria for classification according to Regulation (EC) 1272/2008 or Directive 67/548/EEC, and are therefore conclusive but not sufficient for classification.