Pyrethrin is a natural insecticide derived from the flowers of the chrysanthemum plant. It is commonly used to control a variety of pests, including mosquitoes, flies, and fleas. Pyrethrin works by affecting the nervous system of insects, leading to paralysis and death. This compound is often found in household insect sprays and garden products due to its effectiveness and relatively low toxicity to humans and pets when used properly. However, it can be harmful to aquatic life, so care should be taken when using it near water sources.