There are many tried and proven methods of food sterilisation for trade that do not involve using nuclear materials.

When food production methods pay strict attention to hygeine much of the need for sterilisation is alleviated. Where it is necessary, food producers and importers have a choice.

Good hygiene practices in food production, processing, handling and storage can alleviate problems of rodent droppings, bird excreta, insects and any other causes of food contamination.

Two relatively commonly used post-harvest insecticides are EtO (ethylene oxide), and MB (methyl bromide). These are volatile chemicals which are sprayed onto the food. Both of these chemicals leave potentially unacceptable levels of chemical residues, and so non-chemical alternatives are preferred.

The physical disinfestation method should be used wherever possible. Other alternatives include temperature control, oxygen deprivation/controlled atmosphere, steam treatment and steam sterilisation/encapsulation.

There are several known ways of killing insect pests. These may vary according to the type of fruit, because of the different tolerances for different treatments. Some of these are cold storage, heat/steam, hot water dips, and atmospheric control such as with oxygen, carbon dioxide and nitrogen. There are also physical disinfestation methods and inspection and culling of infected fruits. Combinations of these methods may also be used.

• Cold storage kills fruit fly in grapefruit
• Steam treatment kills some forms of fruit fry in mangoes
• Hot water dips kills insects in bananas and pawpaws
• Variations in atmosphere control ie. varying the proportion of carbon dioxide, oxygen and nitrogen, that have been found suitable for insect control in some fruits.
• The USA Department of Agriculture has developed an “acoustic coupler” which detects fruit fly larvae vibrations when the larvae eat the fruit. Infested fruit can then be removed.
• Picking unripe fruit can overcome the problem where the fruit does not contain the insect pest in its green and unripe state.
• Fruit has been found to be free of infestations if it is within a set distance limit from a known infested area. [1]

[1] Australian Consumers Association, Food Irradiation - An Inquiry, 1987.

The greatest food losses occur in warm, moist, lesser-developed countries, where the capital is lacking for existing storage technologies such as refrigeration, and other atmospheric controls. Considering that food irradiation is a technology far more expensive and complex than these, it is questionable that it should be considered as a viable option. Other very simple solutions include cardboard boxes for packing, and silos that excluded rats.

With regard to meat and seafoods, the sources of infection could be removed. For example, farming of free-range chickens, and paddock grazing of other livestock reduces the chance of infection. Ensuring that animal feed is clean, and locally produced would also assist. Slaughter and evisceration processes would also need to adhere to the strictest hygiene standards - instead of the highly mechanised, less thorough forms that could increase chance of infection, and that some larger food processors seek (due to its cheaper cost). Some seafoods are caught, or farmed, in infected waters, which also leads to contamination. Addressing this “bigger picture” pollution issues is also desirable.

Ultimately, less centralised food production and distribution is the most sustainable solution.

Safer irradiation technology exists

The main problem with a Co-60 source rack is that it is highly radioactive 24 hours a day, every day of the year. Other suggested radiation options are electron beam and X-rays. These sources of radiation are supplied via high voltage electron accelerators that are powered by electricity, and the radiation beams are turned off when the power is turned off.

Electron beam has a shorter penetrating distance than X and gamma rays, but is sufficient if bulk packaging is removed from most goods.

The benefits of electron beam and X-rays over Co-60 are:

They avoid the transportation dangers inherent in the continual exchange of radioactive Co-60 from Canada (every 12 to 15 months)

They can be turned on and off, therefore the plant can be shut down over night or during holiday or maintenance periods. This not only reduces the dangers to workers, but also vastly reduces the leakage of radiation outside the building.

The ability to produce radiation depends on the supply of electricity. Should an accident occur that disconnects the power supply (eg earth tremor), the machine is automatically and immediately rendered safe, unlike a Co-60 system which can experience electric and physical failures as demonstrated by the 3 accidents at Australian irradiation facilities outlined in the document titled Some of the Known Accidents at Nuclear Irradiation Plants Around the World. In the event of a natural or human-caused disaster, It would take hours or even days to mitigate the damage from Co-60. Procedures would involve covering the Co-60 with sand, or concrete, and even then would not be a final solution to the problem of radioactive containment.

The electron or X-ray beam is focussed in a particular direction, compared to the Co-60, which emits randomly in all directions from the source. Therefore the electron or X-ray beam can be more effectively shielded, further reducing the leakage of radiation from the chamber.

Modern?

The field of radiotherapy used to use Co-60 quite extensively for treatment of tumours. For the reasons presented above, Co-60 treatment machines are now being replaced by the safer X-ray technologies in the form of Linear Accelerators, although tiny Co-60 sources of the order of mCi are still used (compare this to the 300,000 curies of radiation in Steritech’s plants).

In the final analysis, the push for food irradiation is a campaign for a certain model of food production. It is a campaign for a capital-intensive, trade-orientated and global model of food production, distribution and consumption.

The use of food irradiation to increase global trade in food

• gives the advantage to larger companies that can afford the technology
• further homogenises the food market and family farmers are put at a greater disadvantage
• means that more of our fruit, vegetables and meat will come from other countries - and will be older, more bland and less nutritious (as well as with more dangerous chemical by-products)
• results in closure of local/domestic farms, and loss of agricultural jobs.

Environmental impacts include the land degradation and loss of wildlife habitat impacts of industrial agriculture, the contamination impacts of the production, use, transportation and storage of radioactive materials, and the effects of increased fuel consumption through increased transportation.

The use of food irradiation is in direct contrast to local, autonomous and sustainable food systems. Commercial food irradiation requires centralisation and highly capital-intensive infrastructure. Those adversely affected are consumers, small-scale farmers, and communities with unwanted developments forced upon them.

Contrary to claims that food irradiation provides a convenient ‘solution’ to food safety, it is one more step in a variety of food processing techniques; heating, refrigeration, use of chemical additives, reduction of oxygen and moisture, packaging and hygienic handling. Food irradiation adds to the complexity of food processing because it does not necessarily replace any of these existing technologies, and in addition, reduces the nutritional content and changes the chemical composition of the foods.

It should also be noted that irradiation only kills off the current population of the contaminating organisms, and the same processes that would prevent infestation or contamination would need to be used in addition to the technology. Another important consideration is that much of the research on efficacy of irradiation as a treatment is done overseas, in conditions different from those experienced in Australia. It could not, therefore, be concluded that foods will react in exactly the same way, or that all contaminants would be eradicated. Research into the effects of transportation on irradiated foods is also not available, and some foods become more intolerable to injury after irradiation.

With community mobilisation, both in Australia and internationally, focussing on the impacts of trade liberalisation agendas on communities, food irradiation could well be included on the list of issues of public concern. Whilst neither a market, nor a practical need exists for the use of this technology, profit for companies is seen to be the sole driver of its promotion.

The alternative to longer shelf life or storage time is the support of local production, distribution and consumption of fresh foods. A decentralised food system is more socially and economically empowering for communities.