In summary, a conservative estimate of potential cancer risks from consuming ETO in uncooked spices in New Zealand indicated no significant risk. However, retail samples, and fumigation trial data from the United States and New Zealand show that the breakdown products, ECH and EBH, remain at considerable concentrations
in spices for a relatively long time. There is some evidence that both compounds may be mutagenic and/or carcinogenic. The only in vivo toxicology data on ECH have been negative for carcinogenicity and mutagenicity. However, an oral carcinogenicity study is needed to ascertain whether ECH is a potential carcinogen
when eaten, and to give an estimate of any dose–response relationship leading to the development of a cancer potency factor.