The Risks - Allergies and Toxicity of Edible Insects

Even when eating edible species of insects and handling with them, problems may arise. As with other foods, edible insects can also be associated with a number of food safety issues. Consumption of inappropriate developmental stages, wrong culinary preparation, handling without protective equipment or collection of insects in unsuitable areas may result in adverse reactions.

An important area of food safety consideration is the quality and safety of the feed or substrates used for rearing insects: the nutrient content and food safety aspects of reared insects depend on the substrate.

The use of raw materials that are alternative to conventional feed are being explored as potential substrates for mass production of insects.

Some of these raw materials include food side streams such as food waste, agricultural by-products or manure from livestock farms. The high nutritional content and low cost of such side streams provide a means to enforce circular economy in the process, in addition to further reducing the environmental footprint and economic costs associated with insect farming.

Allergy, a potentially life-threatening condition, has at its heart an overly zealous T-helper type 2 response to environmental antigens. We are constantly flooded by potential allergens, both airborne and ingested. Inhalation and/or contact with airborne particulate insect products has resulted in sensitivity to insect proteins and is manifested by such common entities as dermatitis, conjunctivitis, rhinitis, asthma, contact urticaria or rhinoconjunctivitis. In most cases, allergies to insects are associated with a job where employees deal with insects.

In clinical practice in relation to insects, most often reported allergic reactions are to chitin which is the second most abundant biopolymer in nature, where it protects crustaceans, parasites, fungi, and other pathogens from the adverse effects of their environments, hosts, or both.

Chitin is not commonly deemed a potential allergen but can cause sensitization through frequent exposure. Allergic reactions have been documented primarily in various types of mealworm and Orthoptera, both contact and respiratory form. Combined allergies to more species of insects are common.

Exposure to chitin (from dust mites, mould, shellfish or insects) might be the primary external determinant in allergy development. Intermittent low-level exposure could induce allergy in genetically-predisposed individuals.

A zoonosis is an infection or infestation that is shared by humans and animals. Insect rearing for food and feed has not yet been practiced long enough to determine the risk of disease transmission. However, since insects are taxonomically quite distant from humans compared with conventional livestock, the risk of zoonotic infections is expected to be low. Nevertheless, particular attention should be paid to pathogens that initially have animals as their host, but could then shift to humans as their preferred host. The lack of studies on safety issues and hygienic handling of insects highlights the need for more research in this area.