I find this on of the safest and most efficient ways of using cypermethrin. The compound can be a weak contact poison on the skin resulting in red itchy spots for some humans but formulations with a higher concentration of the active ingredient are allowed in lice shampoo. It is not efficient resorbed via skin and efficiently metabolized by adults when ingested. It can be enriched in milk and fatty tissue of mamals. I t is widely used as insecticide in agriculture and due to bioaccumulation, up to 30 microgram per kg of product of this insecticide are allowed in cow products and fish. Clinical cases of poisoing always involve improper use of spray formulations, as inhalation exposure is most toxic to humans. If you wear gloves while using, wet the tip and wash the floors(without prior sweeping to avoid dust in the air) in the morning before letting you kids play, this is the safest way to use such an insecticide.