What type of insecticides kill insects that come into contact with treated surfaces?

The term "contact poisons" refers to insecticides that are designed to kill insects when they come into direct contact with surfaces that have been treated with the chemical. These types of insecticides penetrate the insect's body through the exoskeleton upon contact, disrupting their physiological functions and leading to their demise.

Contact poisons are particularly effective for surface applications where insects crawl or rest, allowing for the insecticide to be absorbed and exert its lethal effect. This can include various formulations used in pest control, such as sprays or powders, which create a residue on surfaces where pests are likely to traverse.

In contrast, repellent poisons deter insects from approaching treated areas but do not kill them upon contact. Inhalation poisons require insects to breathe in the toxic substance, affecting them through their respiratory system rather than through direct contact. Systemic poisons are taken up by the plant or animal tissues and can kill pests that feed on those tissues, rather than affecting them through surface contact. Thus, contact poisons uniquely fulfill the criteria of directly causing death through physical interaction with treated surfaces.