Pyrethrins are chemicals used in spray insectices.
Pyrethrins are insecticides derived from chrysanthemum flowers that paralyze and kill insects. As a a natural alternative to DEET or other chemicals, pyrethrins are used in a wide variety of insecticide products, including mosquito repellent sprays for skin, treatments for lice, insecticidal pet shampoos, as well as insecticidal bombs or sprays for home use. Many studies have been done on the safety of pyrethrins for human use, and studies show that pyrethrins aren't absorbed through the skin of humans or pets. Does this Spark an idea?
Mosquito Repellents
Even through pyrethrin can kill insects in certain doses, it can repel insects if present in low concentrations. For this reason, pyrethrins are used in mosquito repellents for humans that can be sprayed on the skin. One of the actions of pyrethrins in low doses is called flushing, where the chemical agitates the insects, causing them to leave hiding places. It is this action that repels flying insects in sprays. The low doses in repellent sprays also makes them very safe for human use.
Lice Treatments
Pyrethrins are used in lice shampoos as well as insecticide shampoos for pets. These chemicals kill adult lice, but eggs and baby lice, called "nits," have to be removed with a comb. Many lice shampoos also contain a chemical called piperonyl butoxide, or PBO, that helps kill lice. Some people have reported allergic reactions, like skin irritation, to some pyrethrin-based lice shampoo, but these side effects are rare.
Flying Insect Control
Pyrethrins are used in flying insect control sprays because they provide what experts call "knockdown" for insects like mosquitoes and flies in higher doses. When sprayed on flying insects, these chemicals are absorbed through the exoskeleton and enter the body. They immediately attack the nervous system, disrupting the sodium channels that allow signals to travel along the nerves. With their nervous system compromised, insects die.
Side Effects
While pyrethrins have been tested safe for human use, there are some side effects that have been reported when high levels of exposure are involved. When pyrethrins are used in flying insect control in outdoor areas, they can be inhaled in large doses. Side effects due to high exposure include headache, nausea and dizziness. Occasionally pyrethrin-based sprays can get into someone's eyes due to human error or automatic dispenser malfunction, and this can cause neurological symptoms as well.
Manufactured Chemicals
Pyrethroids are chemically similar to naturally occurring pyrethrins, but they are synthesized in a lab instead of extracted from chrysanthemum flowers. While over a thousand pyrethroids have been synthesized, only a few are used in insecticides for human use. Commonly used synthetic pyrethrins are permethrin, telfluthrin, cypermethrin and bifenthrin.
Tags: have been, absorbed through, chrysanthemum flowers, flying insect, flying insect control