IDENTIFYING, ADDRESSING AND

Identifying, Addressing and

Overcoming Consumer Concerns

A Roundtable on Food Irradiation

Convened by:

Public Voice for Food and Health Policy

National Food Processors Association

International Food Information Council

February 18-19, 1998

Resources for the Future Conference Center

1400 16th Street, NW

Washington, DC

Acknowledgments

Public Voice for Food and Health Policy wishes to thank all those who took time to participate in the Roundtable on Food Irradiation. For most, participation meant a commitment of at least 12 to 2 days. Many traveled substantial distances in less-than-perfect weather to be present. Their willingness to devote time and effort to this undertaking is deeply appreciated.

Additional thanks go to many others who helped with advice and assistance as the Roundtable took shape. This group includes, at the National Food Processors Association, Rhona Applebaum, Tim Willard, Brian Folkerts, Kelly Johnston and Adele Logan-Galen. At the International Food Information Council, thanks go to David Schmidt, Robert Earl and Sylvia Rowe. Also helpful at various stages were Terrie Dort of the National Council of Chain Restaurants, Sara Lilygren of the American Meat Institute, Dagmar Farr of the Food Marketing Institute, Kevin Burke of Food Distributors International, Carol Tucker Foreman of Foreman, Heidepriem and Mager, and Richard Frank, Dennis Johnson and Mazie Cobb of Olsson, Frank and Weeda.

The taste test at the conclusion of the first day would not have occurred without the help of Sharon Beals of IBP Inc., Dennis Olson of Iowa State University, and John Masefield of Isomedix, Inc. IBP supplied the ground beef and coordinated the taste test conducted at D.C. Central Kitchen in Washington, DC. The irradiation was performed by Iowa State University and Isomedix.

Arthur S. Jaeger

Executive Director

Public Voice for Food and Health Policy

Robert Hahn

Director of Legal Affairs & Research

Public Voice for Food and Health Policy

Introduction

On February 18-19, 1998, Public Voice for Food and Health Policy, together with the National Food Processors Association and the International Food Information Council, convened a roundtable discussion at the Resources for the Future Conference Center in Washington, DC. The goal of the Roundtable was to address consumer concerns about food irradiation.

Approximately 40 individuals participated in the Roundtable, with another 40 present as observers. Participants included many of the top government and academic experts on irradiation, representatives of consumer organizations with an interest in food irradiation, and representatives of the food and irradiation industries. The group included both critics and advocates of irradiation, and participants were encouraged to ask tough questions of those on opposing sides. Facilitating the discussion was George Strait, chief medical correspondent for ABC News in Washington.

The agenda for the Roundtable included the capabilities of irradiation; current uses in this country and worldwide; different irradiation technologies and their application to various foods; safety, nutritional, and organoleptic issues; and labeling, consumer acceptance and education. The Roundtable was held as an invitation-only event to encourage a honest exchange of views.

The co-conveners hoped to both initiate a dialogue among consumers, government, academia, and industry and seek consensus. The ensuing discussion was frank and, at times, heated. While no formal consensus was reached, there was common ground among many participants on a variety of points. These included:

! the effectiveness of irradiation against the bacteria of greatest public health concern

! the need for effective processing and handling of food before and after irradiation

! the need for labeling of irradiated foods in an informative, non-threatening way

! the limited impact of the approved uses of irradiation on the nutritional value and taste of foods

! the need to address worker safety and environmental concerns before widespread use of food irradiation

! the value of long-term studies on any effects of eating irradiated food

! the need to educate consumers about irradiation

Rhona Applebaum

Executive Vice President, Scientific Affairs

National Food Processors Association

Richard Bender

Senior Legislative Assistant

Office of Senator Tom Harkin

Christine Bruhn

Director, Center for Consumer Research

University of California, Davis

Kevin Burke

Vice President

Food Distributors International

James Clouser

President

SteriGenics International

Lester Crawford (former

Administrator, FSIS)

Director

Georgetown Center for Food

and Nutrition Policy

Susan Doneth

Safe Tables Our Priority (STOP)

Raymond W. Durante

The Food Safeguards Council

Robert Earl

Director of Public Health

International Food Information Council

Daniel L. Engeljohn

Chief, Standards Development Branch, Food Safety and Inspection Service

U.S. Department of Agriculture

Chester England

Chairman, Food Safety Task Force

National Council of Chain Restaurants

Sandra Eskin

American Association of Retired Persons

Dagmar Farr

Vice President, Consumer Affairs

Food Marketing Institute

Carol Tucker Foreman

(former Assistant Secretary of Agriculture for Food and Consumer Services)

President, Foreman, Heidepriem & Mager, Inc.

Arnold Foudin

Assistant Director for Scientific Affairs, Animal and Plant Health Inspection Service

U.S. Department of Agriculture

Frank Fraser

Vice President of Market Development

MDS Nordion

Edith Furst

Consumer Federation of America

Nancy L. Glick

Director, Nutrition & Consumer Affairs

Hill and Knowlton

Linda Golodner

President

National Consumers League

Dee Graham

Senior Adviser

The EPRI Food Technology Center

Jan J. Groeneveld

Agricultural Counselor to the

United States and Canada

Royal Netherlands Embassy

Robert Hahn

Director of Legal Affairs & Research

Public Voice for Food and Health Policy

Timothy Hammonds

President and CEO

Food Marketing Institute

Patricia A. Hansen

Consumer Safety Officer

Food and Drug Administration

James Hodges

Senior Vice President, Regulatory Affairs

American Meat Institute

Kelly D. Johnston

Executive Vice President for

Government Affairs and Communications

National Food Processors Association

Beth Lautner

Vice President, Science and Technology

National Pork Producers Council

Richard Lechowich

Director, National Center for Food Safety and Technology

Illinois Institute of Technology

Donald Louria

Chairman, Department of Preventive Medicine

and Community Health

New Jersey Medical School

John Masefield

Chairman and CEO

Isomedix, Inc.

Dennis Olson

Director, Utilization Center for Agricultural Products

Iowa State University

Michael Osterholm

State Epidemiologist

Minnesota Department of Health

Donna Porter

Specialist in Life Sciences

Library of Congress

Morris Potter

Centers for Disease Control and Prevention

Sylvia Rowe

President

International Food Information Council

David Schmidt

Vice President, Food Safety

International Food Information Council

Jacob Steinberg

Professor of Pathology

Albert Einstein College of Medicine

Spencer Stevens

President

APA, Inc.

Dennis Stolte

Senior Director, Environment/Food Safety

American Farm Bureau Federation

Irwin A. Taub

U.S. Army Natick RD&E Center

Michael Taylor (former Administrator, FSIS)

King and Spalding

Donald W. Thayer

Research Leader for Food Safety

Agricultural Research Service

U.S. Department of Agriculture

John Woodhouse

Food Distributors International

Stephen A. Ziller, Jr.

Vice President, Scientific and Regulatory Affairs

Grocery Manufacturers of America, Inc.

Summary of the Roundtable

Capabilities and Limitations of Irradiation

Foodborne illness is a serious public health problem in the United States. Irradiation is effective against the bacteria currently of greatest public health concern in the United States, including E. coli O157:H7, Campylobacter, Salmonella and Listeria. Irradiation at pasteurizing doses effectively controls harmful bacteria and parasites in foods. Irradiation is not effective against viruses, toxins or prions.

Dr. Donald Thayer, U.S. Department of Agriculture, summarized the effectiveness of irradiation against foodborne pathogens. He observed that the biological effect of radiation is due to inactivation of DNA. The effectiveness of irradiation against a particular organism depends upon the following factors: composition of the product being treated (including its water content, pH and the presence of certain food additives), irradiation dose, temperature during and after irradiation, atmosphere, packaging, and the sensitivity of the organism in question. The sensitivity of an organism to radiation, in turn, depends upon the organism=s size and complexity, its growth phase and its past history. Generally, smaller and simpler organisms are less sensitive to radiation. The following is a list of organisms in descending order of sensitivity: metazoa, protozoa, vegetative bacteria, spores, viruses, prions. Existing research suggests that radiation has no effect on prions, the term given to the infectious agents that cause bovine spongiform encephalopathy (>mad cow disease=) and other transmissible spongiform encephalopathies. Organisms are most sensitive to radiation in their log phase, less so in the stationary phase, and most resistant in the spore phase. Past history of an organism may also increase its resistance. For example, exposure to an acidic environment may trigger repair mechanisms that increase an organism=s resistance to radiation.

Looking at some common foodborne pathogens, E. coli bacteria are highly sensitive to radiation. In one experiment, ground beef inoculated with 10^4.8 CFU/gram of E. coli O157:H7 irradiated at 1.5 kGy had no detectible E. coli O157:H7 bacteria or toxin even after temperature abuse.^[1] Campylobacter is somewhat more sensitive, and Salmonella and Listeria are somewhat less sensitive, than E. coli O157:H7. However, irradiation at the FDA-approved doses is highly effective against all four bacteria, and the D-values are very close for all four pathogens in all meats. Among protozoa, irradiation is highly effective against both Cyclospora and Toxoplasma gondii oocysts. A dose of 0.5 kGy is sufficient to render either parasite non-infective. Irradiation is generally ineffective against viruses.

Surviving pathogenic organisms are injured by radiation and do not multiply faster in irradiated, as opposed to non-irradiated, foods. Because of a synergistic effect between radiation and heat, surviving bacteria are likely to be killed by mild cooking temperatures, assuming the product has been properly refrigerated prior to cooking.

Regarding the need for irradiation to combat foodborne illness, Dr. Morris Potter, Centers for Disease Control and Prevention, stated that virtually all raw agricultural products that will not be cooked by consumers need pasteurization, whether by irradiation or some other treatment. Given the sporadic occurrence and low levels of pathogens in these foods, he concluded that irradiation is an appropriate pasteurization method for all such foods, except for those in which irradiation produces unacceptable quality changes. Michael Osterholm, Minnesota Department of Health, emphasized the increasing seriousness of foodborne illness in the United States, noting that there were 78,000 hospitalizations for foodborne disease in Minnesota alone last year. He said we are not able to effectively control many of the vectors for pathogens in the natural environment, such as birds, insects and rodents. We are also learning that pathogens may contaminate the interior as well as the surfaces of some foods; for example, Salmonella on the flower of a tomato plant may enter the tomato. Viruses, which are associated with human fecal contamination, may be spread through the increased use of composting in agriculture.

Current and Potential Uses of Irradiation

The Roundtable participants expressed the greatest interest in uses of irradiation that would: (a) improve food safety; and (b) replace fumigants or pesticides currently in use.

Most participants felt that the first logical major application of irradiation should be to eliminate E. coli O157:H7 and other pathogens in ground beef. As Donald Thayer pointed out, ground meat products pose special problems, because a small amount of contaminated meat can potentially contaminate a huge volume of product and thereby make a large number of people sick. He also suggested irradiating tenderized meat cuts, because the pins used to tenderize meat can inoculate the internal surfaces of the meat with bacteria.

There was less agreement about the possible use of irradiation to pasteurize fresh fruits and vegetables. Less research has been done on uses of irradiation to pasteurize produce. Irradiation has been approved for fruits and vegetables up to a dose of 1 kGy, primarily for disinfestation. While a dose of 1 kGy may control some pathogens (the average D-value for most vegetative bacteria is about 0.5 kGy), it would not kill most spores and would provide an inadequate margin of safety for vegetative cells. Moreover, irradiation at the doses likely to be used for produce is generally ineffective against viruses, such as Norwalk viruses and hepatitis A, that may contaminate produce. Finally, although manipulating temperature, atmosphere and dose may alter the effects of radiation to some extent, irradiation at pasteurizing doses is likely to cause unacceptable organoleptic damage to some fruits and vegetables. Alternative treatments, such as ozone, may offer better ways to pasteurize fresh produce.

Irradiation may also be used for control of pathogens in herbs and spices, its most common application worldwide, and for insect disinfestation of fresh fruits and vegetables and grains. It could replace methyl bromide, a highly toxic and ozone-depleting fumigant used to disinfest certain foods in international trade. Dr. Arnold Foudin, USDA, observed that, although the Environmental Protection Agency has proposed a ban on methyl bromide, it may not implement the ban until there is a viable alternative.

Finally, some participants expressed interest in irradiation of livestock feed. Irradiation is already widely used to sterilize feed for laboratory animals. It is also permitted in the treatment of poultry feed. Whether irradiation of livestock feed would be practical depends on economic considerations and whether post-irradiation handling of the feed would undo the effects of irradiation.

Some consumer and academic participants favored a Ago slow@ or gradual approach to the introduction of irradiated foods in the marketplace. A targeted use of irradiation and a gradual introduction of irradiated foods would make it easier to recognize any adverse effects and would be less threatening to consumers. Some participants felt that irradiation should be introduced as soon as possible where the need is great and the application is practical.

Dr. Thayer and Jan Groeneveld of the Royal Netherlands Embassy provided brief overviews of current uses of food irradiation in the United States and Europe. In the United States, a significant and growing volume of spices, about 11 percent, are irradiated although ethylene oxide is still used on some spices. A limited volume of chicken, fruits and vegetables are irradiated and sold in certain supermarkets and restaurant chains. Irradiation is also used to sterilize certain foods fed to the astronauts and hospital patients with weakened immune systems. In Europe, several countries have their own national regulations ranging from the United Kingdom, which is the most liberal, to Germany, which banned irradiation. Vocal consumer opposition in some countries has limited government approvals and use. The Netherlands permits irradiation of several minor productsCincluding fruits, dried vegetables, herbs and spices, shrimp, frog legs and thickenersCbut no Abasic products.@ Because of the patchwork of regulations, trade limits the extent to which any nation can use irradiation. The European Union has thus far only approved irradiation of spices.

Comparison with Other Food Safety Technologies

Irradiation is one of many technologies that can provide an added measure of food safety for certain foods. Irradiation should be viewed as one food safety tool, albeit a particularly effective one, that would co-exist with, rather than replace, other technologies.

The Roundtable did not have time to fully discuss the many other new food safety technologies currently available or being developed for various foods. An industry scientist mentioned some of the many anti-microbial technologies available or being studied for beef including competitive exclusion, chemical de-hairing of carcasses, trisodium phosphate and other rinses, and steam pasteurization. It was noted, however, that these treatments occur at earlier stages of production and processing and, unlike irradiation, do not pasteurize the final product. Dr. Potter argued that, with respect to many foods, we may have reached the limit of the food safety benefit provided by good sanitation. Several consumer group participants expressed a preference for combinations of treatments that cumulatively result in effective elimination of pathogens and expressed reservations about too great a reliance on any single food safety technology.

Food irradiation itself encompasses two different technologiesCgamma sources (cobalt-60 and cesium-137) and machine sources (x-rays and electron beam)Ceach of which involves exposing food to ionizing radiation. Frank Fraser, MDS Nordion, discussed the advantages and disadvantages of cobalt-60. It has deep penetration, so it is possible to irradiate food in its shipping packaging. It is also possible to increase throughput simply by increasing the strength of the source. Its disadvantage is that it cannot be turned off when it is not in use. Spencer Stevens, APA, Inc., said that, while electron beam does not penetrate as deeply as cobalt-60 radiation, it can penetrate to a depth of 3.5 inches if both sides of the product are exposed. Electron beam accelerators can be placed in a food processing plant as part of an on-line operation, and they can be turned off when not in use.

Irradiation Not a Cure-All

Irradiation does not obviate the need for effective processing controls before irradiation nor safe handling practices after irradiation.

Roundtable participants agreed that irradiation would not eliminate the need for, and might actually increase the importance of, effective processing controlsCincluding sanitation, good manufacturing practices, HACCP (Hazard Analysis and Critical Control Points) plans, and performance standardsCbefore irradiation. Irradiation at approved doses was not intended to, and will not, clean up foods that have unacceptably high bacterial loads.

Likewise, there was agreement that irradiation would not obviate the need for safe handling practicesCincluding proper temperature control, handwashing, avoidance of cross contamination and cooking at proper temperaturesCafter irradiation. Even foods irradiated at pasteurizing doses might retain some pathogenic bacteria that could multiply and cause illness if the food is subjected to temperature abuse or is otherwise improperly handled. Irradiated foods, like any other foods, may be contaminated by food handlers or by cross contamination.

There was disagreement, however, on the issue of inspection. Carol Tucker Foreman and the consumer groups were worried that some policymakers might mistakenly assume that irradiation obviates the need for strong government food safety inspection programs. The consumer representatives feared that the introduction of HACCP and irradiation might be used by budget-cutting members of Congress to justify a drastic reduction in federal inspection. To counter this temptation, the consumer groups called on the food industry to speak out publicly in favor of strong federal inspection.

Safety of Irradiated Foods

Irradiation has been approved as safe by the Food and Drug Administration and the U.S. Department of Agriculture for a number of foods including meat, poultry, produce and spices.

At present, irradiation has been approved by FDA for several uses including pathogen control in meat and poultry, microbial disinfection of dry spices and seasonings, and insect disinfestation of other foods. A list of current FDA-approved uses is attached to this Summary as Appendix I. In addition, Dr. Patricia Hansen, FDA, noted that the FDA has received a petition filed by the University of Rhode Island to allow irradiation of shell eggs to eliminate Salmonella enteriditis. Also pending are two petitions to allow irradiation of seafood: one for irradiation of shellfish up to a maximum dose of 1 kGy, the other for irradiation of both shellfish and finish up to a maximum dose of 3 kGy. Both are under review, although FDA is awaiting additional information it has requested from one of the petitioners.

Dr. Patricia Hansen explained the basis for FDA=s determination that irradiated foods are safe. FDA=s analysis considers both toxicological and microbiological safety, as well as nutritional value. Dr. Hansen used FDA=s review of the petition for irradiation of meat and meat products as an example.

FDA=s toxicological review included both an analysis of the chemical changes induced by irradiation and a review of lab animal feeding studies. The agency concluded that the radiolytic products created in irradiated meat are identical or very similar to those in other foods and that their concentrations are so small as to present no toxicological hazard. In its review of the red meat petition, FDA also considered the data from a large number of animal feeding studies, including chronic feeding studies, reproduction studies and teratology studies, among others. These studies included all those in which irradiated flesh foods (red meat, poultry or fish) had been fed to various animal species. In addition, FDA considered data from genetic toxicity studies conducted with irradiated flesh foods. Many of these studies had been previously considered within the context of prior FDA reviews (such as the review of irradiation of poultry up to 3 kGy and the irradiation of certain broad food categories up to 1 kGy), but were re-examined in light of the specifics of the meat petition. FDA concluded that no toxicologically significant adverse effects were observed in any of these studies. FDA further concluded, based on the results of chemical analyses and toxicity studies, that the irradiation of meat does not present a toxicological hazard.

FDA=s microbiological analysis included an extensive review of the literature on the effects of irradiation on microorganisms in raw meat. The agency paid particular attention to spores of Clostridium botulinum, because the spores are radiation-resistant (with D-values ranging from approximately 2 to 4 kGy) and the illness caused by botulinal toxin is so severe. In addition, irradiated meats are likely to be packaged in reduced oxygen or vacuum packaging, and such anaerobic conditions favor the growth of C. botulinum. FDA concluded that the risk of significant growth and toxin production by C. botulinum in irradiated meat stored at proper temperatures is extremely remote. First, C. botulinum spores typically occur at low frequency and at low levels in meat, and their numbers would be further reduced by irradiation at the approved doses. Second, most strains of C. botulinum found in meat do not grow and produce toxin at normal refrigeration temperatures. Even if irradiated and vacuum-packaged meats were subjected to temperature abuse, FDA concluded that the meat would become noticeably spoiled before any surviving C. botulinum spores could multiply and produce toxin. The various species of spoilage bacteria commonly found on meat would generally survive irradiation in sufficient numbers to grow and inhibit growth and toxin production by C. botulinum bacteria.

According to Dr. Hansen, radiation-resistant strains of bacteria have been shown to develop only where bacteria are subjected to repeated, closely spaced sublethal doses of radiation. She said it is highly improbable that such conditions would be created during food processing. It is conceivable that bacteria might be subjected to more than one dose of radiation during food processing. For example, spices might be irradiated at 20 kGy and then incorporated into a meat product that is irradiated at 7 kGy, receiving a total dose of 27 kGy (total dose is cumulative) which would still be below the maximum allowed dose of 30 kGy. In that case, bacteria present in the spices might be subjected to two doses of radiation. However, this scenario would not duplicate the conditions of repeated, closely spaced doses that have been found to induce radiation resistance in the lab.

While most Roundtable participants accepted FDA=s determination of safety, Dr. Jacob Steinberg of the Einstein College of Medicine and Dr. Donald Louria of New Jersey Medical School questioned whether existing research conclusively proved that irradiated foods are not mutagenic. Dr. Steinberg expressed concern with the genotoxicity assays relied upon by FDA to conclude that irradiated foods are not genotoxic. Yet, while arguing that additional genotoxicity studies should be done, he conceded that they are not likely to uncover any problems. Dr. Irwin Taub, Department of Defense, noted that the Joint FAO/IAEA/WHO Expert Committee on the Wholesomeness of Irradiated Food (JECFI) at its 1997 meeting discussed a large number of genotoxicity studies that have been conducted in many countries and concluded that irradiated foods are not genotoxic. Other participants observed that the Paterson Institute for Cancer Research, Christie Hospital and Holt Radium Institute in Manchester, UK has fed radiation sterilized feed to at least 160 generations of lab mice without any evidence of ill effects.

Dr. Donald Louria raised the issue of polyploidy and chromosomal damage caused by consumption of irradiated foods. He said he was aware of only two studies that had examined this question in human subjects. The first, a study conducted at the National Institute of Nutrition in Hyderabad, India found a higher incidence of polyploidy in lymphocytes of malnourished children fed freshly irradiated wheat.^[2] The second, a Chinese study, he claimed, found increased incidence of polyploidy at a Aborderline statistical level.@ He argued there is still a need for a well-controlled study in humans to prove that eating irradiated foods does not cause polyploidy. Most other panelists, however, strongly disagreed with his assessment. Referring to the discussion of this issue in J.F. Diehl=s book Safety of Irradiated Foods, they said that the Hyderabad study was poorly conducted; the researchers only examined 100 cells from each of five subjects. They also took issue with Dr. Louria=s characterization of the Chinese study. One participant observed that the authors of the Chinese study, which examined 1,000 cells from each of 70 subjects, interpreted their results as indicating no increased incidence of polyploidy.^[3] Another participant noted that several studies in animals have been unable to confirm increased polyploidy.

In response to these doubts about safety, Dr. Hansen also said that FDA reviewed a tremendous volume of literature on irradiated foods and found the weight of the evidence was heavily in favor of their safety.

Robert Hahn and some of the other consumer group representatives said they had faith in FDA=s determination of safety. Even though existing evidence indicates that irradiated foods are safe, they felt it is still possible that safety problems might be discovered at a later date. The consumer participants proposed that scientists continue to study irradiated foods and that USDA and FDA consider some form of post-marketing surveillance of irradiated foods.

Studies of Long-Term Health Effects

Despite the large body of research on the safety of irradiated foods, there have been few, if any, controlled long-term studies in humans on the health effects of eating irradiated foods. Many participants felt it would be prudent to collect such data if proper studies can be designed.

Several participants noted that some human populations have been consuming irradiated foods for years with no evidence of adverse health effects. These include Japanese consumers who eat irradiated potatoes, Israeli soldiers who eat irradiated chicken, French and Dutch consumers who eat irradiated shrimp and other foods, and South African soldiers who eat irradiated rations. A government participant said that a list of places where irradiated foods have been eaten over time will appear in a WHO study group report to be published later this year. However, participants were unaware of any controlled long-term studies of human populations that eat irradiated foods.

It was suggested that some follow-up of populations eating irradiated foods on a long-term basis would be prudent. Other participants, however, pointed out that it would require many person-years of follow-up to detect any statistically significant effect. One participant also noted that, in most countries where irradiated foods have been introduced, it would be hard to differentiate cases (persons who eat irradiated foods) from controls (persons who do not eat irradiated foods). Nevertheless, if proper studies could be designed, many participants felt it would be worthwhile to do so.

Nutritional Value of Irradiated Foods

Research indicates that FDA-approved uses of irradiation have a limited impact on the nutritional value of foods. Certain vitamins, including Vitamins A, B1 (Thiamin) and E, are sensitive to irradiation under certain circumstances. Some Roundtable participants expressed concern abut vitamin depletion where:

! The food being irradiated is a significant source of the vitamin affected; and

! Irradiation, either by itself or in combination with other treatments, would produce a significant depletion of the vitamin affected.

Dr. Patricia Hansen discussed FDA=s review of the nutritional adequacy of irradiated foods, using the meat approval as a model. FDA=s review focused on the B vitamins and particularly vitamin B1 (thiamin), because it is sensitive to radiation and because one meat, pork, is a significant source of thiamin. FDA concluded that irradiation of meat would not adversely affect nutritional status. The agency determined that, even if all the pork in the United States were to be irradiated, this would produce at most an eight percent loss in thiamin in the U.S. diet. Since all segments of the U.S. population currently receive the Recommended Dietary Allowance (RDA) for thiamin, an eight percent loss would not cause a thiamin deficiency among any segment of the population. Dr. Hansen said that FDA also considered exaggerated reductions in thiamin levels in irradiated poultry and seafood in assessing the potential consequences of high consumption of irradiated flesh foods on the nutritional quality of the diet. FDA concluded that, even assuming such exaggerated reductions, irradiation would not result in an adverse effect on the total dietary intake of thiamin. FDA also concluded that macronutrients and minerals were not affected by irradiation.

Dr. Hansen said that, when FDA considers whether to approve a petition to allow a new use of irradiation, FDA=s nutrition review takes into account all existing approved uses of irradiation. As it does with other food additives, FDA considers cumulative exposure, assuming a hypothetical person who eats irradiated versions of all food approved for irradiation. Although the issue has yet to be raised, if FDA found that a petitioned use of irradiation would result in a major vitamin loss, the agency would consider that petition, and possible regulatory restrictions, Avery carefully.@

Some Roundtable participants expressed serious concerns about vitamin depletion caused by irradiation. One academic participant noted that acute foodborne illness which irradiation is intended to prevent afflicts a small percentage of the population, while any nutritional loss caused by irradiation potentially affects everyone. Some participants also expressed concern about the effect of any vitamin loss on special subpopulations, especially low-income Americans. Fortification was suggested for consideration where vitamin loss is a concern. One participant proposed that labeling on irradiated foods should declare the amount of nutrient loss.

With regard to specific foods, Dr. Louria questioned FDA=s determination that depletion of thiamin in meat would not adversely affect the nutritional status of any population groups. He said that studies done by his medical school had found vitamin deficiencies, including thiamin deficiency, in elderly persons.^[4] Dr. Hansen maintained that FDA=s data show that average thiamin intakes for all segments of the U.S. population are at or above the RDA. The RDAs include a safety factor to take into account variations in intake. In addition, most dietary thiamin comes from cereal grains.

One academic participant also inquired whether irradiation of fish would impact omega-3 fatty acids. Dr. Thayer said that he was only aware of a limited amount of research into irradiation of fish, since FDA has not approved irradiation of seafood and since some fish species cannot be irradiated because they are too fatty. Irradiation of talapia had no effect on omega-3 fatty acids. Dr. Taub also pointed out that the pattern of effects of radiation on fatty acids is well established and that no significant impact on omega-3 fatty acids would be expected.

One consumer group participant questioned whether irradiation of fruits and vegetables, especially at doses above 1 kGy, would cause significant loss of vitamins. Dr. Thayer said that relatively little research has been done on the nutritional effects of irradiating produce at doses above 1 kGy. Dr. Louria argued that, while the consumption of fruits and vegetables is known to prevent certain cancers, it is not known which of the many substances in fruits and vegetables are cancer-preventive. Therefore, it is not possible to measure the effect of radiation on those substances.

Finally, some participants expressed concern about the possibility of irradiating nuts and grains, which are important sources of vitamin E, another vitamin known to be sensitive to radiation. Some studies have found a synergy between the effects of irradiation and other treatments, such as cooking, on vitamin E loss.^[5] Dr. Thayer said that nuts are unlikely to be irradiated, because they do not pose a food safety hazard and because irradiation of foods with such a high fat content causes rancidity. Dr. Hansen noted that foods that are significant sources of vitamin E typically have a relatively high fat content and therefore are unlikely candidates for irradiation. If they were irradiated, it would most likely be at a low dose or in a reduced-oxygen atmosphere in order to avoid undesirable organoleptic changes, and both of these conditions tend to minimize vitamin loss.

Organoleptic Effects of Irradiation

Research indicates that irradiation at FDA-approved does has a minimal impact on the organoleptic properties of foods. A blind taste-test among Roundtable participants found no discernible taste differences between irradiated and non-irradiated ground beef.

Dr. Dennis Olson, Iowa State University, spoke about the effect of irradiation on the organoleptic properties of meat and poultry. He said the organoleptic effects were generally minimal. Irradiation at approved doses produces no changes in texture or juiciness. Changes in smell are dependent on the dose and the conditions under which the product is irradiated, he said. These conditions include packaging, atmosphere, temperature, and fat and water content. Irradiated ground beef is initially darker, but lightens during display.

At the end of the first day of the Roundtable, participants were invited to take part in a taste test comparing irradiated and non-irradiated ground beef. Ground beef (75 percent lean) was provided on request by IBP, Inc. Participants were offered four different types of ground beef: non-irradiated ground beef, ground beef irradiated at 3.6 kGy using an electron beam accelerator, ground beef irradiated at 1.8 kGy using an electron-beam accelerator, and ground beef irradiated at 1.8 kGy using a cobalt-60 source. These doses approximate those that might be used to pasteurize ground beef for commercial sale. Irradiation was conducted by Isomedix, Inc. (cobalt-60 sample) and by the Meat Lab at Iowa State University (e-beam samples). All ground beef was irradiated in a refrigerated state, held for two weeks, made into patties, frozen, and thawed two weeks later for the Roundtable. The ground beef patties were then cooked on a griddle at D.C. Central Kitchen before being served; cooking times and temperatures were not strictly controlled. Participants were offered samples of each type of ground beef on unmarked color-coded plates. Participants were then asked to complete a questionnaire ranking each sample on a scale from 1 to 4 in the following categories: raw appearance/odor, cooked appearance/odor, flavor, and overall palatability. Nineteen of the Roundtable participants took part in the taste test.

As a group, those who participated in the taste test reported no differences between irradiated and non-irradiated ground beef. In terms of overall palatability, the ground beef irradiated at 1.8 kGy by electron beam received the highest rating, although the difference in the ratings was not statistically significant. A copy of the results of the taste test, including representative comments by participants, is attached to this Summary as Appendix II.

Worker Safety in Irradiation Facilities

Roundtable participants agreed that workers safety and environmental concerns must be addressed prior to widespread commercialization of food irradiation. Irradiators must obtain federal, state and local regulatory approvals and adhere to good irradiation practice guidelines.

Linda Golodner, National Consumers League, raised the issue of worker safety. All participants agreed that procedures to ensure worker safety are essential. James Clauser of SteriGenics International stated that workers in his company=s plants are exposed to no irradiation and wear dosimeters to ensure zero exposure.

It was noted that irradiation plants using gamma ray sources, such as cobalt-60, must be licensed by the Nuclear Regulatory Commission, but electron-beam accelerators in food processing plants are regulated by the radiologic health divisions of state health departments. Ms. Golodner stated that the poultry industry has a dismal worker safety record and will require a great deal of oversight if E-beam machines are ever to be installed in its processing plants. She also questioned the record of the NRC and argued that not all safety violations are reported to the NRC. She proposed that workers in both irradiation facilities and food processing plants that use irradiation equipment should be given whistle-blower protection.

Consumer Acceptance of Irradiated Foods

The Roundtable discussed recent research suggesting that most consumers are willing to accept irradiated foods if they are educated as to the purpose and safety of irradiation. There was general agreement that additional consumer research and education is needed.

Dr. Christine Bruhn presented an overview of research on consumer attitudes toward irradiated food. Annual surveys conducted by the Food Marketing Institute have found a shift in concern among consumers from chemical and pesticide contamination to microbiological contamination; bacteria now ranks highest among consumers= food safety concerns and is increasing. When asked about irradiated foods, FMI=s 1997 Trends survey found about 33 percent of consumers surveyed felt irradiation was a Aserious concern,@ and about 56 percent expressed Asome concern@ or Aserious concern.@ The FMI surveys have found consumers are less concerned about irradiation than about bacteria or pesticides, while an AMI/Gallup survey found about the same level of concern for irradiation as for chemicals and preservatives.

Some marketing studies have found that consumers favor irradiated over non-irradiated foods and that some consumers may even pay a higher price for irradiated foods when given a choice. A recent unpublished Kansas State University study found that about 60 percent of consumers bought irradiated instead of non-irradiated chicken when both were sold at the same price. When consumers were provided with educational material, 80 percent of consumers chose the irradiated chicken.^[7] Nevertheless, several participants felt that consumer research findings need to be corroborated by actual marketing experience. A relatively small number of supermarkets and restaurants in the United States currently offer irradiated foods on a regular basis. A supermarket in the Chicago area has successfully been selling irradiated chicken and produce labeled as such for several years. The fact that irradiated food is being sold in the market is, in itself, considered an endorsement by many consumers. Dr. Timothy Hammonds, Food Marketing Institute, presented his conclusions from FMI=s many consumer surveys on irradiation. He said that the Acollective wisdom of the public@ on issues of this kind is impressive, and educators should not Atalk down@ to consumers. The introduction of irradiated foods must be done Awith consumers.@ Dr. Hammonds said that grocers are willing to play their part, provided that irradiated foods are clearly labeled and consumers are educated about the benefits of irradiation. He called for a public education campaign on food irradiation and invited consumer groups to participate, but he said that the educational campaign should not be overdone. For example, information should be offered to shoppers in the grocery store, not mailed to them at home.

Robert Earl, International Food Information Council, summarized the preliminary findings of six focus groups conducted by Axiom Research Co. of Cambridge, Massachusetts for the International Food Information Council. The focus groups were held in New York City, Dallas and Los Angeles in January and February 1998 and included men and women representing a mix of ages, races, and educational and socio-economic levels. During the focus groups, participants were asked to read an editorial from USA Today. IFIC=s research expands upon earlier consumer attitude surveys and research presented by Dr. Bruhn and is the first focus group research to evaluate specific messages on food irradiation that could be used in future education campaigns.

IFIC found that most consumers will accept irradiation along with other measures to improve food safety. Most are willing to try irradiated foods, but they will not compromise on taste. Consumers are far more accepting if irradiation is being used to improve food safety than if it is used to extend shelf life, and some consumers said they did not want produce with longer shelf lifes. Many consumers were willing to pay a premium up to several cents per pound for irradiated foods that are safer. A small minority of the focus group participants were Aholdouts,@ those who said they would not eat irradiated foods under any circumstances.

According to IFIC, consumers want a choice between irradiated and non-irradiated foods, and they want irradiated foods to be labeled. Consumers liked the radura symbol which they found appealing, but consumers felt the symbol alone was insufficient. As for the text to accompany the radura, consumers liked Airradiated for your safety,@ Airradiated to eliminate harmful bacteria,@ and Acold pasteurization (irradiation).@ Consumers also want to be educated about irradiation.

Some industry participants were less sanguine about consumer acceptance of irradiated foods, especially when anti-irradiation groups take out full-page ads attacking irradiated foods or picket stores or restaurants selling irradiated foods. One participant said the key question to ask survey respondents and focus group participants is Awould you feed irradiated food to your children?@ David Schmidt, International Food Information Council, said that the IFIC focus groups included parents who said they would provide their children with irradiated foods because of concerns about foodborne illness. He felt that most consumers are able to see through extreme language on both sides, both fear-mongering by irradiation opponents and exaggerations by irradiation proponents.

On the issue of consumer education, most participants agreed that food processors, distributors and retailers, as well as food service employees and consumers, would need to be educated about the continuing need for safe handling and cooking practices. While some industry participants proposed that government be involved in consumer education and one participant proposed the Surgeon General publicly affirm the public health benefits of irradiation, the consumer groups argued that the federal government should not be part of an educational campaign. They argued that the government should not promote one food safety technology over others and that the limited federal food safety budget would be better spent elsewhere.

Labeling of Irradiated Foods

Roundtable participants generally agreed that irradiated foods should continue to be labeled, subject to existing exceptions. However, participants were open to variations on existing label languageCsuch as Acold pasteurization (irradiation)@Cthat would provide an informative, truthful and non-threatening way to notify consumers that a particular product has been irradiated.

Dr. Patricia Hansen reviewed the FDA=s labeling requirements for irradiated foods. FDA requires that the retail packaging of irradiated product bear the radura symbol and a statement Atreated with radiation@ or Atreated by irradiation.@ The label may add certain additional statements such as Ato reduce bacteria@ provided such statements are truthful and non-misleading. For products not in packaged form, the labeling must appear on signage. The FDA labeling requirement does not apply to Asecond generation@ products, products that contain an irradiated ingredient but are not themselves irradiated. FDA does not mandate any color or type size for the labeling. The requirement of labeling language originally had a sunset clause, and FDA intended to discontinue the text once consumers became familiar with the radura symbol. However, since few irradiated foods have been marketed, this has not been possible and FDA has made the labeling language a permanent requirement. Dr. Hansen showed a table of other countries= labeling requirements for irradiated foods and noted that no country uses a symbol alone. The Food and Drug Administration Modernization Act of 1997 states that no provision of the Federal Food, Drug and Cosmetic Act shall be construed to require that a separate irradiation disclosure statement be more prominent than the declaration of ingredients. Although FDA=s current labeling regulation does not require that the irradiation disclosure statement be more prominent than the declaration of ingredients, the agency plans to amend its regulations to clarify this point. Dr. Hansen said that FDA has been and still is open to specific suggestions for label improvements provided the label remains truthful and non-misleading.

Dr. Hansen said FDA initially decided to require labeling of irradiated foods, because the agency deems irradiation to be a material fact that might not be apparent to the consumer without such labeling. It is deemed material, because irradiation may alter such properties as the organoleptic qualities or the shelf life of foods, and, in the absence of labeling, consumers would not expect these differences.

Dr. Daniel Engeljohn, USDA, noted that FSIS has separate regulations governing the labeling of irradiated poultry. For poultry, FSIS requires a green radura symbol and the words Atreated by irradiation@ to be prominently displayed on the principal display panel. There is currently no labeling regulation for pork, because no irradiated pork is being marketed, but an FSIS policy states that meat products containing irradiated pork may need to be labeled depending upon how much irradiated pork they contain. In this, FSIS policy and FDA policy diverge, since FDA does not require labeling of irradiated ingredients. FSIS intends to issue a proposed labeling rule for meat shortly.

All Roundtable participants who addressed the issue supported labeling of irradiated foods, with the exception of the National Food Processors Association which questioned the legal and scientific basis for requiring labeling of irradiated foods and felt that the current labeling requirement would deter some consumers. Most participants felt that labeling should be required to inform those who seek to purchase irradiated foods as well as for those who want to avoid them. Eliminating the label, they felt, would eliminate consumer choice. It would also likely raise a Ared flag@ for consumers. Carol Tucker Foreman commented that, where there are already doubts in the public mind about something, altering established practices will only strengthen those doubts. She suggested that food manufacturers embrace the label and use it in competitive advertising. One industry participant, however, argued that promotion of irradiated foods as safer would improperly imply that non-irradiated foods may be less safe or unsafe.

On the contents of the label, most participants agreed that the word Airradiation@ or some variant thereof should appear on the label. Brian Folkerts, National Food Processors Association, felt strongly that use of the word Airradiation@ alone has negative connotations for many consumers. He and a few other participants favored the term Acold pasteurization@ by itself. He also felt it was unclear whether the radura symbol may be seen as a warning by some consumers.

Some participants felt the labeling language could be altered to sound less threatening while continuing to use the word Airradiation.@ Dr. Taub suggested that the label should distinguish between irradiated foods that are pasteurized and those that are sterilized. He suggested Airradiation pasteurized@ and Airradiation sterilized@ or some variation of these terms. Other participants favored Acold pasteurization (irradiation)@ or Acold pasteurized (irradiated).@ Other cold pasteurizing technologies, such as ozone or high pressure, could then be inserted in the parentheses as applicable. Dr. Engeljohn cautioned that it would first be necessary to establish a consistent definition for the term Apasteurized@ across all commodities.

Glossary

D-value: The radiation dose necessary to reduce the initial population of a bacterial pathogen by 90 percent. For each pathogen, the D-value will vary depending on such factors as the specific food, the physical state of the food (frozen versus nonfrozen), temperature and ambient oxygen level.

kGy (kiloGray): One thousand Gray. A Gray is a unit measure of radiation dose equal to one joule of energy absorbed per kilogram of matter being irradiated. The Gray is the unit of radiation absorbed dose used by the International System of Units (or SI, from the French ASysteme internationale@), the worldwide official system of units of measure since 1986. One Gray equals 100 rad, a unit formerly used to measure radiation absorbed dose.

log phase: The logarithmic growth phase is the phase during which bacteria grow or multiply most rapidly.

metazoa: Parasites that are larger organisms than protozoa. They include such parasites as Trichinella spiralis and Anisakis.

oocyst: The zygote, or egg, produced during reproduction by protozoa.

polyploidy: The occurrence of cells containing two or more times the normal number of chromosomes. Human cells normally have 46 chromosomes. Polyploid human cells therefore have 92 chromosomes and occasionally 184 or more chromosomes.

spore: Spores are the so-called Aresting stage@ of certain bacteria in which the bacterial cell becomes enclosed in a tough, resistant coat in response to adverse environmental conditions. On return to less adverse conditions, the spore can germinate and revert to its normal vegetative state. The spore-forming bacteria include Clostridium botulinum, Clostridium perfringens and Bacillus cereus.

stationary phase: The phase during which bacteria grow or multiply less rapidly.

Appendix I

Foods Permitted to be Irradiated under FDA=s Regulations

Food Purpose Dose

Fresh pork Control Trichinella spiralis 1 kGy max./O.3 kGy min.

Fresh foods Growth and maturation inhibition 1 kGy max.

Foods Anthropod disinfestation 1 kGy max.

Dry enzyme

preparations Microbial disinfection 10 kGy max.

Dry spices/seasonings Microbial disinfection 30 kGy max.

Poultry, fresh

or frozen Pathogen control 3 kGy max./1.5 kGy min.

Frozen meats (NASA) Sterilization 44 kGy min.

Refrigerated meat Pathogen control 4.5 kGy max.

Frozen meat Pathogen control 7 kGy max.

Appendix II

Product EvaluationCIrradiated Patties, Washington, DC, February 18, 1998

The purpose of this review was to determine the acceptability of irradiated (1.8 kGray and 3.6 kGray) hamburger patties versus untreated patties.

Results SummaryC19 Participants

Test	Raw Appearance/Odor	Cooked Appearance/Odor	Flavor	Overall Palatability
Blue 1.8 kgray E Beam	1.84	1.94	2.17	2.69
Yellow 3.6 kgray E Beam	2.89	2.31	2.72	2.3
Red 1.8 kgray Gamma	2.03	1.69	1.81	1.94
Green Untreated	1.92	1.97	1.89	2.13

Test

Raw Appearance/Odor

Cooked Appearance/Odor

Flavor

Overall Palatability

Blue

1.8 kgray

E Beam

1.84

1.94

2.17

2.69

Yellow

3.6 kgray

E Beam

2.89

2.31

2.72

2.3

Red

1.8 kgray

Gamma

2.03

1.69

1.81

1.94

Green

Untreated

1.92

1.97

1.89

2.13

Comments and Ranking

! Place the rank (1 the best, 4 the worst, ties are acceptable), in the smaller column and your comments in the larger column for each of the categories.

! Please evaluate the cooked poduct first before looking at the raw products.

! Use whatever condiments you wish and note if your comments are based on product with or without condiments.

Miscellaneous Comments

! No essential difference in appearance or color.

! No essential difference with condiments in flavor (2).

! All products satisfactory (2).

! No significant difference.

! Differing degrees of doneness masked some of the product differences.

! Differences were very minute.

Comments SummaryC19 Participants

Test	Raw Appearance/Odor	Cooked Appearance/Odor	Flavor	Overall Palatability
Blue 1.8 kgray E Beam	$ Slightly darker in the tray (2) $ Normal	$ Not quite as well cooked (2) $ Slight off odor (4)	$ Slight off flavor $ Tastes old $ Very good $ Dry (2) $ Moist (2) $ Bland taste $ More flavor $ Control?	$ Excellent $ OK $ Good (2)
Yellow 3.6 kgray E Beam	$ Slightly darker $ Color less red	$ Slight off odor (2) $ Little different odor, not ob- jectionable $ Good appear- ance, looks juicy $ Less well done	$ Not bad flavor $ Bland $ OK $ Raw notes $ Good flavor	$ Very good $ Irradiated? $ OK $ Dry $ Good (2) $ Objectionable
Red 1.8 kgray Gamma	$ Darker	$ Good odor /appearance $ Juicy hambur- ger odor	$ OK (2) $ Slightly juicer $ Good $ Dry	$ Very good $ Little tougher $ Best overall $ Very acceptable $ Good (2) $ Dry $ Least juicy
Green Untreated		$ Slight pungent odor $ Slight irrradi- ation odor $ Good odor $ Burnt/well done $ Great appear- ance	$ Slight off flavor $ Best due to cooking $ Good beefy fla- vor $ Excellent flavor $ Grilled notes more pro- nounced $ Juicy $ More flavorful $ Most flavor $ OK $ Little dry $ Good	$ Home taste $ Excellent $ Moist $ Good (2)

Test

Raw Appearance/Odor

Cooked Appearance/Odor

Flavor

Overall Palatability

Blue

1.8 kgray

E Beam

$ Slightly darker

in the tray (2)

$ Normal

$ Not quite as

well cooked (2)

$ Slight off odor

(4)

$ Slight off flavor

$ Tastes old

$ Very good

$ Dry (2)

$ Moist (2)

$ Bland taste

$ More flavor

$ Control?

$ Excellent

$ OK

$ Good (2)

Yellow

3.6 kgray

E Beam

$ Slightly darker

$ Color less red

$ Slight off odor

(2)

$ Little different

odor, not ob-

jectionable

$ Good appear-

ance, looks

juicy

$ Less well done

$ Not bad flavor

$ Bland

$ OK

$ Raw notes

$ Good flavor

$ Very good

$ Irradiated?

$ OK

$ Dry

$ Good (2)

$ Objectionable

Red

1.8 kgray

Gamma

$ Darker

$ Good odor

/appearance

$ Juicy hambur-

ger odor

$ OK (2)

$ Slightly juicer

$ Good

$ Dry

$ Very good

$ Little tougher

$ Best overall

$ Very acceptable

$ Good (2)

$ Dry

$ Least juicy

Green

Untreated

$ Slight pungent

odor

$ Slight irrradi-

ation odor

$ Good odor

$ Burnt/well

done

$ Great appear-

ance

$ Slight off flavor

$ Best due to

cooking

$ Good beefy fla-

vor

$ Excellent flavor

$ Grilled notes

more pro-

nounced

$ Juicy

$ More flavorful

$ Most flavor

$ OK

$ Little dry

$ Good

$ Home taste

$ Excellent

$ Moist

$ Good (2)

^[1]Thayer, DW and Boyd, G. Elimination of Escherichia coli O157:H7 in Meats by Gamma Irradiation. Appl. Environ. Microbiol. 1993; 59:1030-34.

^[2]Bhaskaram, C and Sadasivan, G. Effects of feeding irradiated wheat to malnourished children. Am. J. Clin. Nutr. 1975; 28:130-35.

^[3]Brynjolfsson, A. Results of Feeding Trials of Irradiated Diets in Human Volunteers: Summary of the Chinese Studies, published in Proceedings of the FAO/IAEA Seminar for Asia and the Pacific on the Practical Application of Food Irradiation held in Shanghai, April 7-11, 1986.

^[4]Baker et al., Vitamin Profiles in Elderly Persons Living at Home or in Nursing Homes, versus Profile in Healthy Young Subjects. J. Am. Geriatrics Soc. 1979; 27:444-50.

^[5]Diehl, JF, Safety of Irradiated Foods, Marcel Dekker Inc., New York, 1995, pp. 256-57.

^[6]Pohlman, AJ, Wood, OB and Mason, AC. Influence of Audiovisuals and Food Samples on Consumer Acceptance of Food Irradiation. Food Technology. 1994; 48:46-49.

^[7]Fox, John A., and Olson, Dennis G., Market Trials of Irradiated Chicken, forthcoming in Radiation Physics and Chemistry.