Originally published 1988: revised January 2003 for IICPH
Basic to the question of food irradiation is an understanding of wellness or health. Food is not just another form of “pills” or an inert pile of chemicals. One doesn’t choose to have “sickly” chicken or to eat moldy looking eggplant for the evening dinner. A healthy plant or animal is able to balance harmful and healthful bacteria so that it maintains its normal size, shape, texture and colour. Even a child can distinguish between a rotten apple and red juicy wholesome apple freshly picked.
Conventional human wisdom has identified freshly caught fish and game, freshly picked fruits and vegetables, and healthy domestic animal meat as the best nourishment for humans. Once the fruit is picked or the animal killed, it can no longer perform its balancing task and the forces of death and decay begin to take over. The decay process can be slowed through various means such as dehydration, cooking or heat processing, freezing or the newly proposed irradiation process. None of these has the ability to differentiate between desirable and undesirable bacteria. None has the ability to remove pesticide or herbicide residue, toxic nonliving material, or even all bacteria, yeasts or molds. Completely dead food loses its taste, colour texture and attractiveness. It also loses vitamins and other nourishment.
With this in mind, the comparative benefits and disadvantages of food irradiation can be briefly sketched, including an assessment of the need for new food processing methods, the scientific studies on the wholesomeness of irradiated foods, and the political and economic climate under which the technology is being promoted.
Although patents for food irradiation were taken out as early as 1921 in the U.S.A and 1930 in France, the technology was not implemented. In 1957 irradiation of spices was permitted in West Germany under the assumption that spices make up only a small percentage of any food. This permission was withdrawn in 1958 and all food irradiation was banned. Canada permitted irradiation of potatoes in 1960 to prevent sprouting, i.e. that is to make the potato sterile, and in 1963 the U.S.A. granted permits for irradiation of wheat, potatoes and bacon for export. The U.S. food and Drug Administration withdrew the permit for bacon in 1968.
The impetus for food irradiation has not come from farmers, the developing world, retail grocers or consumers. In the early 1970’s the international Atomic Energy Agency (IAEA), whose mandate is to promote nuclear technology, began to hold seminars on food irradiation and established a joint committee of experts from IAEA, the World Health Organization (WHO) and the Food and Agricultural Organization (FAO). This group, the Joint Expert Committee on Food Irradiation (J.E.C.F.I) decided in 1976 that the new chemicals called radiolytic products, which are produced in irradiated food, do not need to pass tests of toxicity as do other food additives. It declared irradiation to be a process not an additive, although free radicals (highly reactive molecules) and new chemicals are produced in the food. Some of these radiolytic products are the same as those produced in cooking or thermal processes, for example hydrogen peroxide and formaldehyde, but they occur in larger proportions in irradiated food. Other by-products are unique to the irradiation process.
The question of classification of food irradiation as a process or and additive is not trivial. Food additives must be tested for toxicity. Food processes do not require such testing. In this case, there is a need for new legislation to cover “additives attributable to processing”, requiring toxicological testing of the new chemicals produced by irradiation.
In Canada, irradiation of potatoes was done for a short period of time in the 1960’s, but was then discontinued. Presently potatoes are not being irradiated. On September 10, 1987, Health Minister Jake Epp, disregarding most of the recommendations of the Canadian Consumer and Corporate Affairs Standing Committee on Food Irradiation, declared Ottawa ready to consider proposals to irradiate food. On June 4th 1988, Health and Welfare Canada published Food Irradiation Regulations in the Canada Gazette. Two experimental irradiation facilities have been recently built in Laval and St. Hyacinthe Quebec; one by Atomic Energy of Canada Limited Radiochemical Company (AECL – RCC) and the other by Agriculture Canada. An experimental linear accelerator will be tested in 1988 at the AECL Whiteshell Facility in Manitoba. There was little public debate on the issues before these Federal initiatives.
EXPORTING A QUESTIONABLE TECHNOLOGY
In the summer 1988, Environics’ public opinion poll reported that 75% of Canadians are opposed to the irradiation of their food. Faced at home with stiff opposition to food irradiation, it appears that AECL has been mounting an aggressive marketing campaign aimed at the developing world. This is leaving AECL open to charges from these countries that they are “dumping” a technology on them, which is not acceptable to Canadians at home.
A case in point is the Canadian governments’ agreement to spend 4.4 million dollars through the Canadian International Development Agency (C.I.D.A.) for the construction of a food irradiator in Thailand. As part of the deal, Canada has apparently agreed to import irradiated mangoes, papayas and shrimps. The arrangement was signed September 10, 1987; the day Jake Epp declared the Federal Government ready to accept requests from the Provinces to irradiate food. There is still no permit in Canada to sell irradiated food from Thailand as was promised.
POTENTIAL PROBLEMS WITH IRRADIATION
In thermal food processing there is a rather homogeneous reduction of all bacteria, both the relatively harmless and those that are pathogenic or toxin producing. In irradiation, bacteria are killed in a proportion relative to their sensitivity and resistance to radiation. Some of the bacteria, which produce the natural indicators of unwholesomeness in food, i.e. staleness, disagreeable smell or unpleasant taste, would be killed off while some of the most pathogenic bacteria would be left alive. For example, Clostridium Botulinum resists irradiation below the 10-kilogray upper-limit for food processing. The toxin produced by Clostridium Botulinum can cause botulism. It flourishes in anaerobic (oxygen free) conditions. This deadly pathogen would not be destroyed by irradiation and in fact could even thrive. Irradiated food requires some protection against re-contamination but the anaerobic growth-enhancing environment for Clostridium Botulinum rules out the use of vacuum-sealed cans for this purpose. The “old fashioned” canning of food done in the proper manner effectively eliminates botulism food poisoning.
Irradiation can kill some bacteria, those most sensitive to it, but it never removes toxins already deposited in the food. For this reason, the cleanliness and health of food chosen for preservation can never be neglected. Moreover, food irradiation should not be allowed to replace sanitary handling of food.
The nuclear industry is promoting food irradiation primarily as a preventative action against Salmonella in poultry. From 1983 -1985, there were 28 deaths in Canada attributed to Salmonella poisoning. Present statistics are unknown at this time. The report of the standing committee on food irradiation from 1983 – 1985 notes that:
“Relatively rough extrapolations have indicated that Salmonella may have contributed to approximately 750 deaths in Canada in 1985, but actual statistics attributed only 28 deaths to Salmonella from 1983 to 1985. Which figures may be more accurate is unknown at this time, but Salmonella contamination is a major source of food poisoning and a significant public health concern in Canada and elsewhere.”
Salmonella contamination is due to improper handling techniques by processors, handlers, consumers and restaurants. Mechanical cleaning of chickens (which bursts the gut) is the single greatest cause of the problem. According to an article by economist R. Krystynak, irradiation of poultry ranks sixth out of eleven methods of food processing investigated to control Salmonella poisoning on a cost/benefit analysis basis. (“Current Concerns – Food Irradiation An Economic Perspective”, Food Market Commentary, Ottawa, Agriculture Canada September 1986)
The Joint Expert Committee on Food Irradiation (J.E.C.F.I) declared (with a disclaimer) that there would be no toxicological problems with irradiated food not exceeding an average dose of 10 kilograys. It gave no specified minimum to ensure the killing of radiation sensitive bacteria; nor did it specify a maximum, which would avoid the production of radiolytic by-products or stimulation of the production of known harmful pathogens. It is well known that irradiation can increase the production of some extremely toxic aflotoxins by certain fungi, especially nuts and grains. These aflotoxins are known to be extremely potent carcinogens and their ability to continue production following irradiation has not been addressed by the Joint Committee. Proposing and average exposure only leaves this technology open to widespread misuse.
Pesticides and other Chemical Hazards in Food
Irradiation fails to eliminate pesticide residues and other chemical hazards in food. It has been proposed as an alternative to pesticides and preservatives. However pre-harvest pesticides will still be used, and their chemical interaction with irradiation is unknown. Irradiated food will still require cooking, freezing, preservatives and other means to avoid re-contamination.
Loss of Nutrients
Some key vitamins, especially E, C and Thiamine are lost through irradiation. The production of hyper oxides apparently reduces the concentrations of fatty acids and fat-soluble vitamins. This may in turn influence absorption and utilisation of the food.
PROMOTION OF IRRADIATION BY THE NUCLEAR INDUSTRY
The Science Council of Canada released a document: “Issues in Food Irradiation” (with a disclaimer) by Susan Mills in April 1987. The publication received assistance from Agriculture Canada, and representatives from Health and Welfare, Consumer and Corporate Affairs, Grocery Products Manufacturers of Canada, the Consumer’s Assoc. Of Canada, Atomic Energy Control Limited, the Nuclear Accelerator Associates, and the ionizing Energy Co. of Canada Ltd. The paper admittedly had two goals:
“To raise public awareness of food irradiation, and emerging technology in which Canada has the potential to build a new industry, mainly oriented to promising overseas markets and second, to build a consensus among government and private sector decision makers about what has to be done to realize the domestic and export potential” (Preface, pg 7).
In brief, the Science Council produced and distributed – free of charge at taxpayers’ expense – a public relations document for the nuclear industry.
The document from the Science Council of Canada is quite selective of information. For example, pages 27 -28 describe the U.S. Army’s 10-year study of the wholesomeness of irradiated food. There is no mention that industrial Bio-Test Limited, hired by the U.S. Army to conduct these tests, was convicted in 1983 of having done fraudulent research for government and industry.
ASSESSMENT OF U.S. FOOD IRRADIATION RESEARCH
There have been about 2000 research papers on food irradiation published internationally. The U.S. Food and Drug Administration selected about 400 for serious review. They chose 6 “considered by agency reviewers to be properly conducted, fully adequate by 1980 toxicological standards, and able to stand alone in support of safety” (U.S. Federal Register). Two studies were in English, three in French and one in German. Upon investigation, in one of the English language papers, published in 1964, the authors state, (about their own research): “consequently in many cases statistical comparisons were not possible. However, examination of data intuitively suggests that the differences have no real significance.” There were differences between the control rats and rats fed irradiated wheat, with a statistically significant increase in stillbirth rate among those fed irradiated wheat. Other findings failed to reach significance because of the small number of animals. This hardly constitutes strong proof of the safety of food irradiation.
The second English language paper reported unexplained deaths and abnormalities in animals given irradiated food, not reaching statistical significance because of the small number of animals in the study. One of the studies indicated negative effects on older animals, but the finding was not pursued. The food used in the English language studies had been irradiated at 20 kilorad (equivalent to 0.2 kilogray), fifty times below the proposed level of irradiation of human food, i.e. below the 10-kilogray average.
In two of the three French studies, the dose to food was less than 50 kilorad (0.5 kilogray). No adverse effects were reported. In the German study, animals fed irradiated food weighed significantly less than controls and had reproductive abnormalities. Both of these effects were mitigated with administration of vitamins.
Certainly no scientist would accept these studies with low dose irradiation of food well below the proposed level, small number of animals, short follow-up time and negative results, as firmly establishing the safety of irradiated food.
THE CONTROVERSIAL REPORT FROM INDIA
Health and Welfare Canada generally depends on the U.S. Food and Drug Administration and the JECFI for their review of the scientific literature. For example, the Science Council quotes the F.D.A. rejection of the abnormal blood cell findings reported by the National Institute of Nutrition, N.I.N., Hyderabad, India, 1976, in children and animals fed irradiated wheat:
“A committee of Indian scientists critically examined the techniques, the appropriateness of experimental design, the data collection and the interpretation of NIN scientists…this committee concluded that the bulk of these data are not only mutually contradictory, but are also at variance with well-established facts of biology.”
It turns out that the “committee of Indian scientists” was two persons: Dr. P.C. Kesavan and Dr. P.V. Sukhatme, appointed to resolve a dispute which arose when the Indian nuclear establishment, Bhabba Atomic Research Center, refused to accept the NIN findings. The NIN had immediately terminated their use of irradiated wheat to feed the children when polyploidy was noticed. The children’s blood slowly returned to normal. The NIN tested their findings on laboratory animals. Sukhatme and Kesavan, refused to look at the NIN animal studies as being “outside of their frame of reference”.
Even this committee’s limited report was not available to the F.D.A., which had made their judgement on a leaked-abridged version. Obviously data on negative health effects of irradiated wheat ingested by malnourished children deserves more serious attention by supposed scientific bodies, especially when food irradiation is being proposed for use in developing countries.
IONIZING RADIATION BREAKS CHEMICAL BONDS
Both the U.S. F.D.A. and the Science Council of Canada attempt to minimize the effects of food irradiation by quoting a report from Ames, Iowa, July 1986, (Report No. 9, Council for Agricultural Science and Technology) saying that each kilogray of ionizing radiation breaks only 6 chemical bonds out of 10 million in food. This makes the magnitude, the nature and the biological impact of the breaks seem small. However, in 100 millilitres (or 0.1 litre) of water there are 5-gram moles, that is 1025 molecules. At the low-dose of one kilogray, 6 times 1018 chemical bonds are broken creating the hydroxyl radical, one of the most reactive entities known in biochemistry. Water makes up some 80% of most foods. Food irradiation will be permitted to an average dose of 10 kilograys. There is no maximum permissible dose mentioned in the regulations.
Labelling requirements for irradiated food offer no assurance to the consumer that food has not been irradiated because there is no test to detect irradiation.
The flower-like radura symbol is misleading and should be accompanied with the word “Irradiated”. The wording should appear on all foods that have irradiated ingredients. The proposed labelling exemption for irradiated ingredients that comprise less than 10% is not acceptable. A food could contain six ingredients, each one less than 10% of the whole, which together comprise 45% of the product. All irradiated ingredients at any percentage in the food product should be listed.
The IICPH sees little Canadian benefit in food irradiation other than economic gain for Canada’s nuclear industry. In the U.S., it can be shown to benefit the nuclear weapons industry since it will require commercial reprocessing of nuclear fuel rods to separate out the cesium 137 requirements. For the farmer, the consumer and the developing world, it means higher priced food, less nourishment in the food and probable harmful side effects in terms of pregnancy outcomes, cancers and chronic diseases. The IICPH recommends complete cost/benefit analysis of food irradiation and much more well- designed scientific testing of its impact on health. Both should be independent of the industries that tend to profit from the technology, for without this assurance, food irradiation becomes a massive experimental program on humans.
The Canadian and American public are justifiably concerned over the unknown effects of the irradiation of food. Consumer resistance will and should continue until these effects are known and quantified. Toxicological testing should be mandatory.
Scepticism by Canadian consumers in regard to food Irradiation can only be increased by the failure of the Government of Canada to follow the recommendations of the Standing Committee on Food Irradiation.
Export of food irradiation equipment to developing countries at this time is premature and exploitative.
Not covered in this brief report are questions of worker exposure, accident potential and waste disposal from this experimental technology.
The IICPH is grateful for research assistance on this issue from Food and Water Inc., Probe International, the Food Chain, the National Institute of Nutrition of India, testimony from the U.S. Congressional Hearing on Food Irradiation and the New Jersey State Assembly public hearing on food irradiation.
In particular, we are grateful for the research of Donald B. Lauria, M.D., Professor and Chairperson of the Department of Preventive Medicine and Community Health, New Jersey Medical School; George Tritsch, Ph.D., Cancer Research Scientist, Roswell Park Memorial Institute, Buffalo, New York; and Richard Piccioni, Ph.D, Senior Staff Biophysicist with Accord Research and Educational Associates, New York City.