Time to Modernize the Law on Food Irradiation

Tag : additive for food



The massive outbreaks of E. coli 0157:H7 in spinach and lettuce in 2006 caused several deaths andhundreds of illnesses and devastated the produce industry. Sincethen, the FDA has been under increasing pressure to approve thepetition -- submitted in 1999 -- to allow irradiation ofready-to-eat food. Irradiation technology could be used to ensuremicrobiological safety of fresh produce. Some national TV networksand many popular and scientific articles (including one by thisauthor) demanded that irradiation be used to provide the necessary"kill step" for pathogens in fresh produce.

In March 2008, Dr. S. Sandlof, Director of the FDA Center for FoodSafety and Applied Nutrition, testified at a Congressionalsubcommittee hearing to launch legislation on food safety. Dr.Sandlof stated that the discovery of "furans" in someirradiated food had caused FDA concerns, hence the delay inconsidering the petition for irradiating ready-to-eat foods. Hebelieved that international organizations were unaware of thiscompound in their earlier evaluations of the safety of irradiatedfood. He expected that the FDA's review process would be completedby the end of this fiscal year.

With regard to the "furans" in irradiated produce, whichappear to be the FDA's "last straw," it is difficult tocomprehend why the FDA has pinpointed this group of compounds (itis not clear whether Dr. Sandlof meant "furan," which isa single compound found in irradiated apple juice as reportedearlier by the FDA, or "furans," which is a group ofcompounds), knowing full well that the quantities detected in someirradiated food were lower than those found in heat-treated foods. The sensitivity of modern analytical instruments would enable us todetect extremely small amounts (ppb levels) of toxic compounds inany foods. Many of these compounds, when tested in purified form,would demonstrate some toxicity to humans.

Among these compounds are benzene, benzopyrenes, acrylamide, andmore. It is nonsense for the FDA to consider minute amounts ofsome compounds (such as furan) in irradiated food while turning ablind eye to the same compound in larger quantities in foodstreated by other processes. International organizations (Food andAgriculture Organization of the United Nations [FAO], InternationalAtomic Energy Agency [IAEA], and the World Health Organization[WHO]) that have monitored the safety of irradiated foods since1960s have been aware of the existence of tetrahydrofuran (not"furans" as indicated by Dr. Sandlof) in irradiated applejuice since 1980. However, the expert committee on thewholesomeness of irradiated foods appointed by the threeorganizations considered the quantity discovered so minute that itdoes not raise toxicological concerns.

But no excuse explains the FDA taking more than eight years toconsider the petition in favor of food irradiation -- submittedwhen George W. Bush was still the governor of Texas and SaddamHussein still ruled Iraq with an iron fist. So much has happenedin the past eight years, but the FDA still appears to be unmoved bythe safety and effectiveness of irradiation as a sanitary treatmentof fresh produce. In view of the many illnesses and lost lives ofpeople who consumed contaminated produce over the past eight years,the FDA should be asked who is to be held accountable. Thesetragic incidents could have been prevented had irradiation beenapproved for sanitizing fresh produce. The Congressionalsubcommittee should also ask whether it is justified to continueclassifying food irradiation as a food additive.

•••

Why it has taken the FDA so long to review the petition onirradiated ready-to-eat foods? Dr. George Pauli, former Directorof FDA Pre-Market Approval, notes that the FDA regulates foodirradiation based on provisions of the Food Additive Amendment of1958, which defines a food additive as "Any substance theintended use of which results or may reasonably be expected toresult, directly or indirectly, in its becoming a component orotherwise affecting the characteristics of any food (including anysubstance intended for use in producing, manufacturing, packing,processing, preparing, treating, packaging, transporting or holdingfood), including any source of radiation intended for any suchuse."

It is likely that food irradiation was incorporated into the 1958amendment because of the lack of scientific knowledge on thetechnology -- especially its safety -- at that time. It should berecalled that 1958 was in the midst of the Cold War and the threatof nuclear war was looming. It was then generally believed thatexposing food to _any_ source of radiation would either induceradioactivity or induce new substances in treated food that wouldbe carcinogenic.

Because food irradiation is regulated as a "foodadditive," the FDA requires scientific evidence to demonstratethe safety of each and every irradiated food, as it would forindividual food additives. A petition must be submitted to the FDAfor each irradiated food along with data demonstrating its safety. If the same food undergoes any treatment or change in itscomposition in any way prior to irradiation, a new petitiontogether with the safety data of the new food will have to besubmitted to the FDA as if it were a new additive.

The FDA's classification of food irradiation as a food additive hasa negative impact worldwide as most, if not all, countries followthe FDA's protocol in regulating this technology. The UKgovernment decided in the early 1990s, however, to approve foodirradiation as a food process, and to regulate irradiated foodsbased on food classes, e.g., fruits, vegetables, cereal grains,poultry, seafood, spices, and seasonings, rather than individualfood items. The International Consultative Group on FoodIrradiation (ICGFI), an inter-governmental advisory body of FAO,IAEA, and WHO, recommended a model regulation, similar to the oneintroduced by the UK government, to all other member countries. Asa result, in the late 1990s, many countries in Asia and thePacific, Africa, the Middle East, and Latin America started toregulate food irradiation as a food process based on food classes. Brazil has taken further action -- it regulates food irradiation asa food process regardless of food products or absorbed dose.

Scientific data accumulated over the past fifty years do notsupport the classification of food irradiation as a food additive. Foods treated by irradiation with cobalt-60 or cesium-137 (eachemits pure gamma rays), electrons generated by a machine withmaximum energy of 10 MeV, and X-rays generated by a machine with amaximum energy of 5 MeV (later changed to 7.5 MeV) do not becomeradioactive. Multi-generation animal feeding studies conductedwith different types of irradiated foods never found any adverseeffects attributable to the consumption these foods. Analyticaldata on radiation chemistry of foods and its components found thateither no new compounds are formed in irradiated foods, or, ifcompounds are formed, that they are the same ones found in naturalfoods or foods treated by other processes (e.g., cooking), or arecompounds of no toxicological significance. In short, there aremore data demonstrating the safety of different types of irradiatedfoods than there are of foods treated by all other processescombined.

•••

The safety of different types of irradiated foods has beenevaluated by national and international experts (including thosefrom the FDA) on several occasions since 1958. In particular,since the early 1960s, the FAO, IAEA, and WHO monitored andevaluated the safety of irradiated foods. From these evaluations,it became clear that:

• No radioactivity is induced in any food treated by the threetypes of radiation sources mentioned above.
• Food irradiation is a physical process for treating foodsimilar to heating and refrigeration of food.
• Toxicity of any irradiated food cannot be demonstrated bycredible scientific data.
• Food irradiated under prevailing good manufacturingpractices is safe for consumption.
• The effectiveness of irradiation as a sanitary andphytosanitary treatment for food and agricultural commodities hasbeen clearly demonstrated.

Based on the foregoing, in 2003, the Codex Alimentarius Commissionadopted an international standard for irradiated food that endorsesthe safety and effectiveness of irradiation as a food process. TheInternational Plant Protection Commission likewise approvedinternational guidelines on irradiation phytosanitary measures inthe same year. The standards and guidelines issued by these twointernational bodies are recognized by the World Trade Organizationin its dispute settlement process in food trade.

The science on food irradiation has progressed significantly from1958 when the FDA started regulating this technology as a foodadditive. The time has come for the FDA to accept modern scienceby regulating food irradiation as a food process, not as a foodadditive. By doing so, it can remove the burden of having toevaluate each and every type of irradiated food each time apetition is submitted. It can then devote its limited resources toregulate foods based on modern science to ensure the safety of foodsupplies for the public.

Meanwhile, the FDA should approve the petition on irradiatedready-to-eat foods, pending since 1999. Such approval will allowirradiation to be used to ensure the microbiological safety offresh produce and other foods to be consumed raw or without furtherheat treatment. By not approving irradiation for this purpose, theFDA in effect has denied the right of the public to safety for awide variety of foods.


Paisan Loaharanu is Adjunct Professor of Food Safety at MichiganState University and Former Head, Food & EnvironmentalProtection, Joint FAO/IAEA Division.

See also: Loaharanu's full report on Irradiated Foods for the American Council on Science and Health.