Facts About Pesticide Spraying for Mosquitos

from Yvonne Homeyer

Many communities in the St. Louis area, including the City of St. Louis and St. Louis County, use pesticide spraying in an attempt to control mosquitoes. In 2002, pesticide spraying increased throughout the St. Louis metropolitan area when West Nile Virus was discovered.

Pesticide spraying is the least efficient mosquito control measure, according to the Centers for Disease Control. Consider these facts:

  • Only a small percentage of mosquitoes in the targeted area are killed by spraying.
  • Pesticide spraying cannot target just mosquitoes. Also killed are beneficial insects such as butterflies and bees (pollinators) and dragonflies (mosquito predators). Birds can be affected as well.
  • Mosquito populations may actually increase after pesticide spraying because natural predators such as birds and dragonflies can also be killed by the pesticides.
  • Mosquitoes develop resistance to pesticides.
  • Pesticide spraying can be harmful to people’s health because the toxic chemicals that kill insects also impact our bodies.

There are alternatives. Integrated Pest Management is a concept that includes prevention (eliminating stagnant water sources which are mosquito breeding grounds), larviciding to kill mosquitoes in their larval stage, public education and awareness, and monitoring of mosquito populations.

FOR MORE INFORMATION or PETITIONS call (314) 963-7750 or check out these web sites:

NOTE: This "Fact Sheet" is available as a separate letter document; in addition, a "Petition" for St. Louis County is also available.