tert-butyl acetate

Endpoint summary

Additional information

The mutagenic/genotoxic potential of tertiary butyl acetate has been characterized in a well-conducted bacterial mutagenicity test, an in vitro chromosome aberration test in human lymphocytes, an in vitro mouse lymphoma study in L5178Y cells and an in vivo micronucleus assay. All four studies were conducted according to current guidelines and are considered key studies. In a bacterial reverse mutation assay conducted according to OECD Guideline 471, there was no increase in mutation frequency in any strain of Salmonella typhimurium (TA 98, TA 100, TA 102, TA 1535, TA 1537) or E. coli (WP2uvrA/pKN101) up to a maximum concentration of 5000 μg/plate in the presence or absence of metabolic activation. Cytotoxicity was evident at the 5000 μg/plate concentration but not at the 1500 μg/plate level. In an in vitro chromosome aberration assay conducted according to OECD Guideline 473, there was no evidence of clastogenic activity when human lymphocytes were exposed at concentrations up to 1160 μg/mL in the presence or absence of metabolic activation. Cytotoxicity was observed at all dose concentrations in the absence of metabolic activation. In an in vitro mouse lymphoma assay conducted according to OECD guideline 476, there was no evidence of mutagenic activity when L5178Y cells were exposed up to 1162 μg/mL in the presence or absence of metabolic activation. At a concentration of 1162 μg/mL, there was no excessive cytotoxicity to the cells.

In an in vivo mammalian erythrocyte micronucleus test conducted according to OECD Guideline 474, there was no evidence of chromosome damage or bone marrow toxicity in rats following nose-only inhalation exposure up to a maximum concentration of 2044 ppm of tertiary butyl acetate for 6 hours. For all studies, vehicle, negative and positive controls induced the appropriate responses. Based on a review of the data from all available studies, the available information for tertiary butyl acetate demonstrates that it is not genotoxic, even at concentrations causing cytotoxicity.  

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Although no in vivo heritable germ cell mutagenicity tests were available for review, the total weight-of-the-evidence available indicates that tertiary butyl acetate is not expected to induce heritable mutations in the germ cells of humans and is not classified for Germ Cell Mutagenicity according to EU CLP (Regulation (EC) No. 1272/2008), and UN GHS.