Furylfuramide (also known as AF-2)[1] is a synthetic nitrofuran derivative which was widely used as a food preservative in Japan since at least 1965, but withdrawn from the market in 1974 when it was observed to be mutagenic to bacteria in vitro and thus suspected of carcinogenicity. This was confirmed later when animal testing[4] found it to cause benign and malignant tumors in the mammary glands, stomachs, esophagi, and lungs of rodents of both sexes, although insufficient evidence exists in human exposure.[3]

Preferred IUPAC name
Other names
AF-2,[1] Tofuron,

2-(2-Furyl)-3-(5-nitro-2-furyl)acrylic acid amide,
a-(Furyl)-b-(5-nitro-2-furyl)acrylic amide,
2-(2-furyl)-3-(5-nitro-2-furyl) acrylamide,

2-Furanacetamide, alpha-((5-nitro-2-furanyl)methylene)-,[2][3]
3D model (JSmol)
Abbreviations AF-2, FF
Molar mass 248.19162
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)
Infobox references

This successful use of bacterial mutagenicity as a screen for carcinogenicity confirmed the use of this methodology as a rapid and efficient test, in comparison to animal testing alone, and led to its further development. The availability of such simpler tests in turn gave rise to greater government oversight and testing of compounds to which the public would be exposed.[5]


  1. ^ a b Nomura, Taisei (1975). "Carcinogenicity of the food additive furylfuramide in foetal and young mice". Nature. 258 (5536): 610–611. doi:10.1038/258610a0. ISSN 0028-0836.
  2. ^ On-Line Medical Dictionary
  3. ^ a b IARC Monographs on the Evaluation of Carcinogenic Risks to Humans (PDF), 31 Some Food Additives, Feed Additives and Naturally Occurring Substances: Summary of Data Reported and Evaluation, World Health Organization, International Agency for Research on Cancer, 1998-04-16, archived from the original (PDF) on 2007-09-29
  4. ^ Hayatsu, Hiroka (1991), Mutagens in Food: Detection and Prevention, CRC Press, pp. 286 pages, ISBN 0-8493-5877-9
  5. ^ Tazima, Y (April 1979), "Consequences of the AF-2 incident in Japan", Environmental Health Perspectives, Environmental Health Perspectives, Vol. 29, 29: 183–87, doi:10.2307/3429062, JSTOR 3429062, PMC 1637377, PMID 389620