According to the EFSA "Consumer exposure to furan and methylfurans in food could lead to possible long-term liver damage. The most exposed group of people are infants, mainly through consumption of ready-to-eat jarred or canned foods. Exposure in other population groups is mainly from consumption of grain-based foods and coffee, depending on age and consumer habits."
Furan and the related compounds 2- and 3-methylfurans are chemical contaminants that naturally form during heated food processing, including cooking. EFSA carried out this assessment following its monitoring of furan levels in food and assessing consumer exposure. Dr Helle Knutsen, Chair of the expert Panel on Contaminants in the Food Chain, said: “Based on animal studies we concluded that liver damage and liver cancer are the most critical health effects". Dr Knutsen continued by saying "Our opinion describes how cooking practices could reduce dietary exposure to furan and methylfurans, bearing in mind that consumers are exposed to them in a variety of foods.”
It is noted "For example due to the volatility of furan, re-heating ready-to-eat meals for infants and young children in a hot water bath without a lid may reduce their exposure by about 15-30%. Different preparation methods for coffee result in different losses of furan concentrations. The losses in boiled/Turkish coffee are 3 to 4 times greater than in filter coffee and espresso."
Source: EFSA