Although it gets some bad press, the process of irradiating food is well understood and tightly regulated.
Take a good look at those crisp lettuce leaves in your salad, or consider the barley that has gone into making your favourite beer or whisky. What these two foodstuffs have in common is that they have both been altered by the process of food irradiation. Lettuce is one of many commercially available foods that owes its longevity to food irradiation, while barley is one of several foods that owes its ancestry to this process.
Food irradiation is the process by which seeds and foodstuffs are exposed to ionising radiation. While this may sound rather Frankensteinian, the procedure has been studied for decades and is well understood. One use for food irradiation is in the creation of new crop varieties. In this case, the radiation acts on seeds to reorganise the cells’ genetic sequence and produce crop plants that either express certain traits (enhanced flavour) or suppress certain traits (susceptibility to certain pests). More commonly, radiation is applied directly to foodstuffs, like herbs, spices and fruit, to arrest or combat pests and stop foodborne illnesses from spreading — these are called phytosanitary treatments.
Radiation used on food can involve various energy levels on the electromagnetic spectrum. This includes gamma rays produced when radioactive elements emit photons: For instance, Cobalt60, the synthetically produced isotope of cobalt, is the main approved radioactive element used to induce mutations in seeds. Other non-radioactive sources include powerful X-rays and high-energy electron beams, which are both produced using electricity. All these rays are akin to the waves produced by a microwave oven, in that they pass through the food or seeds much like microwaves, but they do so without heating it up. And, irrespective of the source and amount of radiation (the dose), the food in question does not become radioactive or reduce in nutritional value.
Doses of radiation can also vary, going as low as one kiloGray (kGy) or as high as 10kGy. This depends on the desired effect — whether vegetables need to be sterilised to feed people with compromised immune systems, or whether genes need to be altered to provide longer lasting vegetables.
Despite the myriad applications of this technology, food irradiation has a contentious history. Nature, primarily the sun, acted as the first known source of radiation; for millennia, plants underwent mutations due to exposure to solar radiation. But the discovery of X-rays in 1895, and that of spontaneous radiation the year after, changed all that.
As the 20th century rolled around, scientists began learning of the capabilities of radiation — that it could destroy insects and produce high yield crops. However, back then, sources of radiation were expensive and hard to come by.
The mid-1940s saw the formation of the behemoth regulatory and oversight organisations, including the United Nations (UN), World Health Organization (WHO) and the Food and Agricultural Organization, the specialised agency of the UN. However, the devastation caused by the use of atomic energy in World War II kept food irradiation off their agenda.
Radiation became tainted due to its inextricable link to the horrors of the war. But US organisations like the US Energy Commission, the military and NASA persisted through the 1950s. They conducted intensive research on how to obtain low-cost sources of radiation to use in peaceful and productive ways, such as sanitisation of food given to astronauts when in space and production of long-life, pest-resistant crops.
In the mid-1960s, the United Nations officially recognised the importance of food irradiation, and established the Joint Expert Committee on Food Irradiation, which was tasked with determining safe food irradiation practices and appropriate doses for human consumption. In 1963, the joint efforts of the WHO and FOA came to fruition with the development and adoption of the Codex Alimentarius, or the Food Code. Since then, the International Atomic Energy Agency (IAEA) has also endorsed the Food Code and worked with various organisations to update the code, and improve the safety and efficacy of food irradiation.
Every country that allows foods to be irradiated must adopt the code and abide by the rules and regulations put forth in it. This helps prevent the misuse of irradiation technology and ensure food supplies stay safe and sanitary. All countries are at liberty to decide what sorts of foods to irradiate, and at what doses, as long as it fits within the regulatory guidelines outlined by the code.
Worldwide, there are over 45 bodies that regulate and endorse food irradiation, including the independent body Food Standards Australia and New Zealand (FSANZ). This organisation ensures that, if food manufacturers want to irradiate anything that is not on the current list, they put in an application detailing how this is beneficial and why it is needed. The FSANZ works with internal and external experts and the government to ensure the food reaching every Australian and New Zealander is safe and of the highest quality. There is also required labelling and an internationally recognised symbol that help consumers know that food has been irradiated. In addition, there are international standards that must be met for the facilities at which irradiation is carried out.
Despite the numerous regulations and rules in place, there are nevertheless many outright sceptics or naysayers regarding food irradiation. Surveys by the FSANZ found that, while a majority of Australians and New Zealanders were aware of food irradiation, 48% and 22% respectively were not accepting of it. Then, of course, there are critics who peddle straight up falsehoods through their websites and blogs, blatantly spreading misinformation about food irradiation and the technologies involved. The individuals who publicise these web pages may think they are doing a public service, but, in reality, these websites can be damaging, spreading fear rather than fact.
In fact, there are researchers at institutes the world over, including some in Australia, who are working tirelessly to understand people's attitudes towards food that been altered by radiation, and to potentially change their beliefs. One such researcher is Heather Bray, an agricultural scientist and science communicator at the University of Adelaide. Through her research, Bray tries to understand cultural and social attitudes towards the use of science and technology in food production. “To me,” she says, “the biggest challenge is how do we get through to those people who think that the food that they are eating is poison.”
This does not necessarily mean that we bombard the public with facts and figures. “It's not just about knowledge, it’s not just about information,” says Bray. “We have to give them the tools to trust us. We need to be able to show that we are credible, that we are reliable, that we’re human and that we share their values. That is where science needs to move now.”
Moving forward, Bray says that scientists also need to be more inclusive. “There’s lots of suggestion that we need to create better dialogue; we need to involve the public in making decisions about what gets done, what gets funded, how the results are analysed. The big challenge is to upscale some of that with the community.”
It all comes down to it being more of a dialogue rather than a monologue. The public, scientists and stakeholders — such as you and I — need to be involved. It’s about listening to the various opinions, taking on board people’s concerns and fears, and not keeping science and technology locked up in the ivory towers of academia. Changes in public behaviour will not happen overnight and may take years, but they are possible with the right attitudes on both sides of the table.
Edited by Andrew Katsis