Irradiating food to prolong its shelf-life may have adverse effect on human health. Flavour, texture, and colour are changed. Vitamins A, C, E, and especially B are damaged by irradiation, rendering valuable foodstuffs useless. Genetic and reproductive irregularities have been observed in association with the consumption of irradiated food. Cancer-causing chemicals known as aflatoxins, created by fungi and occurring naturally in some foods, are produced more abundantly in irradiated food than is normal. The irradiation process itself produces in foods the chemicals called radiolytic products. Micro-organisms in the food may mutate into radiant-resistant strains. Spoiled irradiated meat does not smell putrid, thus eliminating a common warning signal for consumers.
Food may be irradiated twice further exacerbating these effects. For example, potatoes may be irradiated to prevent sprouting and thus prolong storage life, and then used in a prepared meal which is irradiated after packaging.
Irradiation uses gamma rays from a solid radioactive source to disrupt the DNA of, and thus to kill, bacteria, parasites, mold and fungus in and on agricultural products. The process has been known since 1921 when an American scientist discovered it could kill the Trichinella spiralis parasite which can contaminate pork. Commercial irradiators use metallic cesium-137 or cobalt-60 as sources of radiation. Both are waste products from the nuclear industry.
Irradiation causes cancer and foetal abnormalities. At doses of 100,000 rads fruit and vegetable cells are killed, but fungi, bacteria and viruses will not be killed or inactivated and may mutate causing worse contamination.
Irradiation does reduce high levels of pathogen bacteria and parasites, such as flies, maggots, and worms. But food which is so contaminated should be destroyed, not eaten.
In an age when malnutrition is a prevalent danger, destroying the nutritional value of foods is ridiculous. Even if the irradiation of vegetables means that more people have access to such perishable foods, of what use is it if the food has lost all its vitamin and mineral content? It is then only empty calories. Food irradiation is a rich man's toy, providing the wealthy with the means of getting, for example, insect-free papayas from India. The time and money spent on irradiation research would be better employed in increasing local food production, and thus local economic and political strength and self-sufficiency.
Irradiation, which extends food shelf-life from a few days to a few weeks, can greatly aid the distribution of perishable foods to developing countries.
Research in the UK and by WHO has shown that irradiated food is not a health hazard. Any induced radioactivity apparent immediately after radiation is at least one million times less than the naturally occurring radiation. After three days, it is one hundred million times less than naturally occurring radioactivity.
The US Food and Drug Administration approves the use of irradiation to kill harmful bacteria in food, calling it a safe and appropriate procedure.