It is used extensively as an ingredient with insecticides to control insect pests in and around the home, in food-handling establishments such as restaurants, and for human and veterinary applications against ectoparasites (head lice, ticks, fleas). A wide variety of water-based PBO-containing products such as crack and crevice sprays, total release foggers, and flying insect sprays are produced for and sold to consumers for home use. PBO has an important public health role as a synergist used in pyrethrins and pyrethroid formulations used for mosquito control (e.g. space sprays, surface sprays and bed nets).[5] Because of its limited, if any, insecticidal properties, PBO is never used alone.[6]