Adulticides

Adulticides are insecticides used by mosquito control programs to kill adult mosquitoes.

There are many types of mosquitoes. Some are considered a nuisance. They bite people and animals but do not spread germs. Some mosquitoes can spread viruses like West Nile, dengue, or others.

During an outbreak of mosquito-borne disease, local government departments and mosquito control districts take the lead for large-scale mosquito control activities. Depending on the size of the affected area, licensed mosquito control professionals apply Environmental Protection Agency (EPA)-registered adulticides using trucks or airplanes.

Forms of Adulticides

Local government departments and mosquito control districts use liquid adulticides. One way liquid adulticides can be applied is as an ultra-low volume (ULV) spray. ULV sprayers turn the liquid into very small droplets that float in the air and kill flying mosquitoes on contact. Only small quantities of adulticides are needed to kill adult flying mosquitoes in an area.

Liquid adulticides can also be applied as residual sprays. Liquid is sprayed onto vegetation and buildings and allowed to dry. These treatments focus on sites where mosquitoes are likely to land and rest, exposing them to the insecticide. Residual spraying is a special application that is not often used by local government departments and mosquito control districts. They are more commonly applied by pest control professionals.

Types of Adulticides

EPA-registered adulticides have been studied for effectiveness and safety when used according to label instructions. The main types of adulticides available for use in the United States are organophosphates, natural pyrethrins, and synthetic pyrethroids.

Organophosphates

Organophosphates are chemical compounds used to control mosquitoes and plant pests. Organophosphates kill mosquitoes by preventing their nervous systems from working properly. Common organophosphates used by mosquito control professionals in the United States include malathion and naled.

Plant-derived pyrethrins and synthetic pyrethroids

Plant-derived pyrethrins are extracted from some chrysanthemum flowers. Mosquito control professionals use plant-derived pyrethrins, often referred to as pyrethrum, to kill adult mosquitoes using ULV spraying.

Synthetic pyrethroids are similar to natural pyrethrins. Mosquito control professionals use different types of synthetic pyrethroids to kill adult mosquitoes using ULV spraying. Examples of synthetic pyrethroids include permethrin, sumithrin (d-phenothrin), and deltamethrin.

Both plant-derived pyrethrins and synthetic pyrethroids kill mosquitoes by preventing their nervous systems from working properly.

Information on insecticides and health

• The EPA oversees the registration of insecticides.
• The National Pesticide Information Center (NPIC) provides information on human health and insecticides online or through a toll-free number, 1-800-858-7378.