Report of the CONTAM Panel on provisional findings on furan in foodQuestion number: EFSA-Q-2004-109
In May 2004, US Food and Drug Administration (FDA) published the results of a survey of furan in canned and jarred foods that undergo heat treatment (U.S. FDA, 2004). The CONTAM Panel was of the opinion that the available data indicate that this is an emerging issue in food safety and therefore decided to compile a scientific report comprising currently available data on methods of analysis, occurrence, formation, exposure, and toxicity.
Furan is a volatile molecule and headspace gas chromatography and the use of an internal standard is currently the analytical method of choice to quantify furan in foods. Furan occurs in a variety of foods such as coffee, canned and jarred foods including baby food containing meat, and various vegetables, which suggests that there are probably multiple routes of formation rather than a single mechanism which was postulated for flavour volatiles. Fresh vegetables do not contain furan. Only a limited set of data on occurrence of furan in various food categories as well as consumption data are available. In the view of this, the Panel decided to present in the report the range of estimated exposure rather than average exposure. For baby food 273 analyses show furan concentrations ranging from non detectable to 112 µg/kg. Assuming an exclusive intake of commercial baby food in glass jars, corresponding to 234 g food per day, this would lead to exposures ranging from <0.2 - 26 µg furan per day.
Furan can easily pass through biological membranes and is readily absorbed from the lung or intestine. It is rapidly metabolised by P-450 enzymes and cis-2-butene-1,4-dial has been identified as a key metabolite. The amounts of furan reaching body tissues are limited by the high capacity of the liver to eliminate furan from the blood stream.
The toxicity database of furan in is incomplete as no data are available on reproductive and developmental toxicity. There are also no human studies. Furan is cytotoxic and the liver is the primary target organ of furan toxicity after oral application.
Furan is clearly carcinogenic to rats and mice, showing a dose-dependent increase in hepatocellular adenomas and carcinomas in both sexes. In rats, also a dose-dependent increase in mononuclear leukaemia was seen in both sexes. A very high incidence of cholangiocarcinomas of the liver was present in both sexes, even at the lowest dose tested.
Taking into account all the presently available data on the mode of action of furan, the Panel concluded that the weight of evidence indicates that furan-induced carcinogenicity is probably attributable to a genotoxic mechanism. However, chronic toxicity with secondary cell proliferation may indirectly amplify the tumour response.
From the presently available data it appears that there is a relative small difference between possible human exposures and the doses in experimental animals that produce carcinogenic effects, probably by a genotoxic mechanism. However, a reliable risk assessment would need further data on both toxicity and exposure.
Last updated: 30/11/2005