Insecticides are essential for protecting homes, crops, stored food supplies, human health and the natural environment. The large scale application of insecticides became common during the 1950s, and since then, many traditional insect pests have become far less threatening to the public and the economy. Although everyone today is aware of the widespread use of insecticides, very few people understand how they work to control insect pests. For one thing, insecticides do not always come in liquid form. Insecticides can be solid, liquid, granule or aerosol. Airborne insect pests, like mosquitoes, are best controlled with insecticides that are applied via aerosol sprays. While crawling insect pests are best controlled with powders, sprays or granules. All of these methods allow insecticides to be absorbed by the insect pests being targeted, but the manner in which insecticides are absorbed can differ depending on the poisons used.
There are three different ways in which insecticides are absorbed by insects. For example, some insecticides are absorbed through the cuticle of insects. “The cuticle” can be thought of as an insect’s outer skin. This form of absorption is commonly referred to as “dermal entry.” Insecticides that are designed for dermal entry are known as “contact poisons.” Oral entry is another way in which insects can become exposed to insecticides. These insecticides are known as “ingested poisons” and they most often take the form of bait. Insect pests can also inhale poisons through “respiratory entry,” but instead of breathing through a mouth, like humans do, insects breathe through organs known as “spiracles” that are located on their abdomen.
Different insecticides have different bodily effects. For example, Organophosphates are insecticides that interfere with an insect pest’s nervous system. Insect growth regulators are another class of insecticides that interfere with an insect’s growth cycle. These insecticides only work on immature insects, as their growth hormones are altered to cause death during the process of maturation. There are many other types of insecticides in use today, but researchers are most interested in developing biological forms of insect pest control, as biological control strategies may be less costly than traditional types of insect pest control.
