Toxicity Studies of Ethyl Maltol and Iron Complexes in Mice

Ethyl maltol and iron complexes are products of ethyl maltol and the iron found in the cooking pots used to prepare the Chinese dish, hot-pot. Because their safety is undocumented, the toxicity study of ethyl maltol and iron complexes was conducted in male and female Kunming (KM) mice. The animal study was designed based on the preliminary study conducted to determine the median lethal dose (LD₅₀). The doses used in the study were 0, 1/81, 1/27, 1/9, and 1/3 of the LD₅₀ (mg kg body weight (BW)^-1 day^-1) dissolved in the water. The oral LD₅₀ of the ethyl maltol and iron complexes was determined to be 743.88 mg kg BW^-1 in mice. The ethyl maltol and iron complexes targeted the endocrine organs including the liver and kidneys following the 90 D oral exposure. Based on the haematological data, the lowest-observed-adverse-effect level (LOAEL) of the ethyl maltol and iron complexes was determined to be 1/81 LD₅₀ (9.18 mg kg BW^-1 day^-1) in both male and female mice. Therefore, we suggest that alternative strategies for preparing the hot-pot, including the use of non-Fe-based cookware, need to be developed and encouraged to avoid the formation of the potentially toxic complexes.