Methyl tertiary-butyl ether mode of action for cancer endpoints in rodents

Regul Toxicol Pharmacol. 2007 Mar;47(2):156-65. doi: 10.1016/j.yrtph.2006.09.003. Epub 2006 Nov 3.


There are no reports of studies that evaluate if methyl tertiary-butyl ether (MTBE) exposure causes cancer in humans. This evaluation of MTBE carcinogenicity is based on the results of animal studies. A weak tumorigenic response was reported for both MTBE and TBA in one tumor type (kidney) in male rats, for MTBE in one other tumor type (testicular) in male rats, for MTBE in one tumor type (liver) in female mice, and for TBA in one tumor type (thyroid) in female mice. The weight of the evidence does not support a genotoxic mode of action (MOA). Non-genotoxic MOAs have been demonstrated or suggested that correspond to the weak tumorigenic responses. These MOAs either do not occur in humans or humans are much less susceptible to these effects. It is, therefore, unlikely that humans would be exposed to sufficient levels of MTBE to cause these tumorigenic responses.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Carcinogenicity Tests
  • Carcinogens / administration & dosage
  • Carcinogens / toxicity*
  • Endpoint Determination
  • Female
  • Humans
  • Male
  • Methyl Ethers / administration & dosage
  • Methyl Ethers / toxicity*
  • Mice
  • Mutagenicity Tests
  • Neoplasms / chemically induced
  • Predictive Value of Tests
  • Rats
  • Sex Factors
  • Species Specificity


  • Carcinogens
  • Methyl Ethers
  • methyl tert-butyl ether