Martelli A. - Pediatrician - Italian Society of Peditric Allergology and Immunology
The risks associated with the consumption of insect proteins, can be of various kind (1). The microbiological risk is related to the possibility that insects act as vectors for some microorganisms. The chemical risk depends on the hypothesis that insects may be carriers of pesticides or other environmental contaminants. The physical risk occurs exclusively for workers in companies that produce insects for food use. The allergic risk involves children also following the intake of allergenic proteins in food. Indeed, the marketing of partially defatted cricket flour and mealworms has recently been authorized.
If food production is to be achieved using current techniques, increased emissions of greenhouse gases and ammonia, deforestation, soil erosion, loss of plant biodiversity and water pollution are set to continue. For these reasons it is essential to find food sources that can have a minimal environmental impact. Some insects can satisfy these requirements.
It is estimated that the consumption of insects is regularly practiced by at least 2 billion people worldwide. The consumption of insects could lead to the onset of food allergies even in our population that usually does not eat them. We know that in some Countries, where insect consumption is very common, high reactivity frequencies are reported. For example, in China, 18% of food-induced anaphylaxis reactions are caused by the ingestion of insects (2).
Now, the sale of foods based on insect proteins may potentially lead to allergic reaction. In our Country the risk of food allergy for insects, is evaluated for 2% of Italian citizens. For this reason, about 800,000 patients, with the allergy to dust mite, seafood and shellfish can cross react with the tropomyosin that is present in insect also. To protect people at risk, is important that the commercial food reports specific information clearly, regarding the presence of insect proteins, before being placed on the sales shelves. The presence of cricket flour must be showed clearly by a small graphic representing an insect or by the scientific name of the cricket: "Acheta domesticus".
But in which children should we think that the clinical symptoms may depend on an allergy to insect proteins? The diagnosis should be suspected in non-EU children especially, with sensitization to tropomyosin and who maintain, at least in part, their previous eating behaviour, through the purchase of food containing insects in ethnic stores. The molecular diagnostics aimed at identifying specific serum IgE allows the diagnosis of sensitization to insect proteins. The IgE to be identified is directed towards tropomyosin and arginine kinase. The tropomyosin is a protein highly resistant to heat and the various types of food preparation are not able to modify it in the slightest (3). The arginine kinase is susceptible to heat treatment or thermal food processing but is less heat resistant than tropomyosin.
1. Cappelli, A. et al. Insects as food: A review on risks assessments ofTenebrionidae and Gryllidae in relation to a first machines and plants development. Food Control 2020;108:106877
2. Ji K, Chen J, Li M, Liu Z, Wang C, Zhan Z, Wu X, Xia Q. Anaphylactic shock and lethal anaphylaxis caused by food consumption in China. Trends Food Sci Technol. 2009 May;20(5):227-231.
3. De Marchi L, et al. Allergens from Edible Insects: Cross-reactivity and Effects of Processing. Curr Allergy Asthma Rep. 2021;21:35.