Pyrethrin, Pyrethrum and Pyrethroids
Pyrethrins are the active ingredients derived from the natural insecticide pyrethrum, also known as the chrysanthemum daisy.
Pyrethroids are synthetic or manufactured versions of pyrethrins. While they have a similar mode of action, they are more toxic than natural pyrethrins and persist for a longer time in the environment.
Pyrethrins, the extracts of pyrethrum, are less toxic to humans and there is no evidence that they’re stored in the body after exposure, as mammals quickly metabolise and excrete them.
Natural pyrethrins are permitted in organic agriculture because they are degraded, by sunlight and changes in pH, into non-toxic byproducts that are immobile in soil. Once in the soil, they are metabolised by microbes which means the product does not bioaccumulate. When applied appropriately, by the time of harvest they will have broken down, leaving no residue.
Any pesticides permitted for use by organic farmers must be:
- naturally occurring,
- able to break down quickly so they don’t remain as residue in food, and
- not suspected of being unsafe for humans.
That is three ticks for natural pyrethrin.
Natural pyrethrins are also used in products such as laundry powder to get rid of bed bugs, children’s head lice shampoo and of course, The Fly Lady Insect Spray.
Information from Kialla Pure Food. The Organic Grain Millers