“Irradiated food” is related to radiation. Is it harmful to the human body if eaten?

Myth: "'Irradiated food' is related to radiation and is harmful to the human body if eaten"

When shopping in a supermarket, you may sometimes see the words "irradiated food" written on the packaging. Many people, when seeing these words, worry that it may be harmful to the human body and dare not buy it.

Rumor analysis: This statement is not rigorous.

Irradiated food refers to food that has been processed by irradiation technology. The definition of food irradiation in my country's national standard GB18524-2016 "National Food Safety Standard Food Irradiation Processing Hygienic Specifications" is: the irradiation process that uses the radiation chemistry and radiation biology effects produced by ionizing radiation in food to achieve the purpose of inhibiting germination, delaying or promoting maturity, killing insects, killing bacteria, sterilizing and preserving.

Irradiated foods are tightly packaged and do not come into direct contact with radiation sources, so they do not carry radioactivity. At the same time, the radiation intensity is also strictly controlled and will not affect human health. Therefore, "irradiated foods" can be eaten with confidence.

In your daily life, you may come across foods like the following, with the words "irradiated food" written on the packaging. However, when it comes to "irradiation", some people will think of radiation and nuclear pollution, and worry that it will be harmful to health. So, can irradiated food be eaten safely?

Image source: Internet

What is “irradiated food”?

Irradiated food refers to food that has been processed through irradiation technology.

Although "irradiation technology" always sounds like "nuclear radiation" and makes people worry about whether it is harmful to the body, it is actually a very mature sterilization method to maintain food quality. The nutrition of "irradiated" food will not be destroyed, nor will it harm the human body.

The definition of food irradiation in my country's national standard GB18524-2016 "National Food Safety Standard Food Irradiation Processing Hygienic Specifications" is:

The irradiation process uses the radiation chemical and radiation biological effects produced by ionizing radiation in food to achieve the purposes of inhibiting germination, delaying or promoting ripening, killing insects, killing bacteria, sterilizing and preserving.

The picture comes from the Internet

Compared with traditional sterilization methods such as dehydration, heating, and refrigeration, irradiation sterilization has the following advantages:

1. Non-heat treatment

Irradiation sterilization is a cold treatment process that does not significantly increase the temperature of food, making it suitable for heat-sensitive foods such as spices, certain fruits and vegetables. Irradiation sterilization does not change the flavor, color and texture of food, helping to maintain the original quality of food.

2. No chemical residue

Irradiation sterilization does not use chemicals and therefore does not produce chemical residues.

3. Extend shelf life and improve food safety

Irradiation can effectively kill bacteria, viruses, fungi, parasites, their spores and eggs, and has a broad-spectrum bactericidal effect. By reducing the number of microorganisms, irradiation can significantly extend the shelf life of food and reduce the risk of foodborne diseases.

4. Inhibit the rotting and germination of certain agricultural products

Irradiation can cause breakage or cross-linking of DNA molecules in rhizome or tuber cells. This damage can interfere with the normal division and growth of cells. Agricultural products such as potatoes, onions, and garlic are less likely to germinate after irradiation, making them easier to transport and store, thus ensuring food quality.

The picture comes from the Internet

According to the current standards GB14891.1-GB14891.8, the types of food that are currently allowed to be processed with irradiation technology in my country include: cooked livestock and poultry meat, pollen, dried fruits and preserved fruits, spices, fresh fruits, vegetables, pork, frozen packaged livestock and poultry meat, beans, cereals and their products, etc.

What is the difference between “irradiated food” and “radioactively contaminated food”?

"Irradiated food" and "radioactively contaminated food" are two completely different concepts.

The radioactive contamination that food may come into contact with mainly comes from the mining, smelting, production, and application and discharge of radioactive materials in daily life. These pollution sources come into contact with or enter food, causing the food to carry radioactivity. After consuming such contaminated food, its radioactive contaminants may adhere to the human skin and cause external radiation damage, or enter the human body after being digested and cause internal radiation. If the radioactivity of these pollution sources is high, it is equivalent to having an "irradiation sterilization device" on the body at all times, and long-term exposure to radiation will cause damage to human tissues.

The biggest difference between "food irradiation sterilization" and "radioactive contamination" is that the irradiated foods are all tightly packaged and do not directly contact the radiation source, so they do not carry radioactivity. At the same time, the radiation intensity is also strictly controlled. Studies have pointed out that when the radiation dose absorbed in food does not exceed 10kGy (kGy, a unit of absorbed dose, mainly used to measure the energy absorption dose caused by ionizing radiation), there is generally no toxicological hazard.

Due to the particularity of irradiated food, China has always had strict regulations on irradiated food:

On the one hand, the maximum overall average absorbed dose used in various types of food that are allowed to be irradiated is limited, and the relevant maximum overall average absorbed dose is less than 10kGy;

On the other hand, according to my country's national standard GB7718-2011 "National Food Safety Standard General Rules for Pre-packaged Food Labeling", the labeling of irradiated foods stipulates: "Foods treated with ionizing radiation or ionizing energy should be labeled near the food name." "Any ingredients treated with ionizing radiation or ionizing energy should be indicated in the ingredient list." This is why we see the "irradiated food" logo on some foods.

After years of research, irradiation sterilization technology has been widely recognized by the international community. More than 60 countries around the world have formulated regulations that allow the use of irradiation on one or more foods, and hundreds of irradiation plants are engaged in food and medical device sterilization business. Therefore, food that is irradiated and sterilized according to standards can be eaten with confidence.

Looking in the mirror of rumors

Due to the special nature of radiation, people are often afraid of it, and rumors use fear, hope or other strong emotions to attract attention and spread. We should improve our scientific literacy, understand basic scientific principles and research methods, learn the scientific basis and application of irradiation technology in food processing, understand its purpose, process and safety, and avoid being misled by false information.

References

[1] International Atomic Energy Agency. Food irradiation

GB 18524-2016 National Food Safety Standard Hygienic Specification for Food Irradiation Processing

[2] Duan Xin, Ou Jie, Li Bolin. Application of irradiation technology in sterilization and preservation of meat products[J]. Food Science, 2010, 31(1): 278-282.

[3] Qing Lifang, Wei Min, Yang Pinghua, Li Qing, Liu Ying. Mechanism and microbial detection of food sterilization by γ-irradiation. Food Research and Development, 2016, 37(5):218-220

This article is produced by Science Popularization China-Starry Sky Project. Please indicate the source when reprinting.

Author: Su Haozhan popular science author

Review | Ruan Guangfeng, Deputy Director of Kexin Food and Health Information Exchange Center