Photo: Forschungsring e.V.

The production chain of industrially produced foodstuffs is long, and for consumers often extremely nontransparent. Very few people are aware that package foods may be subjected to x-ray quality control, since producers and retailers are not obligated to explicitly declare this. This might be a mistake, as Dr. Uwe Geier explains in this interview. As the scientific director of Wirksensorik GmbH and managing director of Forschungsring e.V., his research examines how even the low levels of x-rays used for product inspection may be altering our food.

As a researcher, you have dedicated many years to the study of foods and their specific effects on people. How did your research turn to the topic of x-ray radiation?
Through cooperation with organic and biodynamic food producers, I came into contact with this topic for the first time in 2012. Although as a food and grocery professional I had been working in this area for a long time, I was completely unaware that certain goods are x-rayed for measurement and quality control. The fact that consumers were not being informed because there was no corresponding labelling requirement became, in essence, the motivation for my subsequent research.

What are the reasons that this method is used?
The purpose is to protect consumers from foreign objects, such as stones or pieces of glass, in their food. Hence, the foods that are x-rayed are usually packaged foods such as preserved fruit and vegetables, bread, and dairy products. Although this procedure makes sense especially for very sensitive products, such as jars of baby food, there are also applications where one really has to asks about the necessity of the scans – for example, when x-rays are used to check the filling height of a package.

How strong are the x-rays that are used to scan our food?
The legal limit is 500 millirays. According to food producers’ own information, they use only a fraction of this – about 1/500th or 1/5000th. This corresponds to about the strength of an x-ray of head and is thus relatively small. Nevertheless, we know from various medical studies that unborn children should be protected from x-rays, and that frequent x-rays scans should be avoided, since even low radiation exposure can increase the risk of tumors.

How common is the use of this technology?
Overall, x-ray examination of packaged foods is probably very common, but at the moment, there is no transparency regarding which companies are concretely using the technology. But it is certainly primarily used by mid-sized and large producers, since the technology is expensive. That’s why small, artisanal companies don’t use it at all. One can also assume that producers of conventionally grown foods use this method more often that organic companies. What is alarming is that radiation can change living things. In general, all radiation damages genetic material. It causes so-called DNA breakages, which the body can repair. But what happens to food when it is x-rayed? The foundational question that has to be answered in this context is: is the food alive? If the answer is no, then the product will probably hardly change at all – neither structurally nor chemically. If it is yes, then we need suitable procedures to observe this life and how it changes.

What could those be?
We know that all living things have a certain, although weak, light radiation. That is why we have used, for example, so-called fluorescence spectroscopy, which can measure the radiation in food. But we also used traditional germination tests, which are used in plant breeding. In addition, we use copper chloride crystallization imaging methods. This produces an image by creating a fluid extraction of the product mixed with copper chloride, which one then allows to crystalize under a glass slide under controlled conditions. This procedure is very sensitive, so one can very easily detect disruptions in the sample. Algae tests also react very sensitively. This is just a small sample of the wide range of tests that we have carried out. We have also used empathic food testing as a method, where the most important instrument of measurement is a human being. If he is attentive, he can tell how food affects him, and possibly even observe direct effects.
In addition, and I find this personally very exciting, we used a chemical method named Alkylcyclobutanone 2ACB. This is so interesting because it is a standard way to demonstrate radiation, although to date not in such small amounts. Our project partner was able to refine the method in order to detect even these lower levels. This is a really great result: in contrast to other methods, which are not completely accepted by all researchers, this is a recognized procedure that complies with European standards.

For you, what were the most impressive results of your investigations?
In a test radiation of goose fat, we were able to detect a measurable change. The x-ray radiation produced certain harmful substances that were not previously in the product. Also, during the empathic food test, in which 60 consumers participated, we discovered that irradiated water was perceived to taste less fresh – despite its only being radiated with a very low level of 1 milligray. In the image production procedure, as well, seven tests of preserved fruits and vegetables from organic producers demonstrated remarkable differences between the irradiated and non-irradiated products, in the form of a strong appearance of aging.

Are there alternatives to the use of x-rays for the quality control of our food?
Thanks to joint workshops with food producers, I know that many of them were very surprised to learn that radiation has an actual effect on their products. In that sense, I think that food producers will now be more cautious with this approach and will critically ask when it is really necessary to use x-rays on their foods. After all, one can use standard methods, like taking samples during production, using human labor and good production practices, to ensure a very high level of food safety and to minimize risks. Naturally, one can also attempt to use additional technology in final checks. Whether there will be a change of opinion here depends less on food producers, but rather primarily on the market, which demands absolute food security, and not recalls and claims. In that sense, the market places high demands on food producers, and demands the use of modern technologies – in part, irrespective of whether their use really makes sense or not.
There are even producers that check their packaged products twice or even three times with x-rays – and that only to document a high degree of product safety. In this case, I would wish that the producers would more carefully consider their processes; and I would wish for better information for consumers so that they can decide for themselves what they want to consume or not. In light of this, some producers might, to set an example, clearly advertise that their products are not subjected to x-ray inspection.