Zenivex E4 (etofenprox)

About Zenivex® E4:

The product name of a mosquito adulticide used by the Project in ULV (Ultra Low Volume) sprayers is called Zenivex® E4.

It is a 4% solution of etofenprox that does not contain piperonyl butoxide. Etofenprox is a reduced risk synthetic pyrethroid with an extremely low toxicity to mammals. It is sprayed from the truck at 4.5-9.0 ounces per minute, at a vehicle speed of 10-15 miles per hour. This presents a minimal risk to humans, pets and non-target species. Etofenprox presents a low toxicity to birds and dried foliar residues are not harmful to honeybees.

Zenivex is an insecticide that contains synthetic pyrethroids, which emulate naturally occurring insecticides known as pyrethrums, found in chrysanthemum flowers. This pesticide kills mosquitoes effectively, yet biodegrades rapidly in the presence of sunlight and/or microorganisms.

Some common pyrethroid products use by consumers include pesticides for common household pests such as ants and wasps; flea and tick shampoos/collars for pets; lice and scabies treatments (shampoos, etc.) for humans; insect repellent clothing, etc. Many pet products contain much higher concentrations of etofenprox, see graphic below:

Comparative Acute Toxicities:

*An LD50 is a measure of toxicity. The longer the LD50 bar, the lower the toxicity. Compared to the active ingredient in other leading mosquito control products, etofenprox, the active ingredient in Zenivex® products, is the least toxic.

Adulticiding with Zenivex® E4:

CMMCP conducts an early evening spray program which runs from approximately Memorial Day to Labor Day. Spraying is done after sunset until midnight. During this timeframe the mosquito is actively seeking a blood meal, and spraying at this time allows us to control the adult mosquito with a minimal risk of exposure to the public or beneficial insects. Weather, mosquito populations and the virus situations determine the actual beginning and end of our spray program.

The type of spraying practiced by the Project is called "ULV" spraying. ULV is an abbreviation for ultra low volume, a method of spraying which allows us to control adult mosquitoes using the least amount of pesticide possible. The spray machines are mounted on the back of pickup trucks, and the applicator drives the vehicle in the area to be sprayed. The vehicle operator controls the spray from inside the vehicle, without needing to shut down the spray machine. These application areas are based on public request, request from local officials or after confirmation of virus, and the Field Technician confirms the presence of a mosquito problem by conducting a landing count (landing counts are suspended after confirmation of virus in Mass.). Please click here for a link to our adulticide procedures.

Generally, there is no need to relocate during mosquito control spraying. The pesticides have been evaluated for this use and found to pose minimal risks to human health and the environment when used according to label directions. Although mosquito control pesticides pose low risks, some people may prefer to avoid or further minimize exposure. Some common sense steps to help reduce possible exposure to pesticides include:

• Listen and watch for announcements about spraying in the local media and remain indoors during the application to the immediate area (please remain inside for 15-20 minutes, or longer at your discretion).
• People who suffer from chemical sensitivities or feel spraying may aggravate a preexisting health condition may consult their physician or local health department and take special measures to avoid exposure.
• Close street-facing windows and turn off the outside setting on window-unit air conditioners when spraying is taking place in the immediate area (you may open windows and activate AC units 15-20 minutes after the application, or longer at your discretion).
• Do not let children play near or behind truck-mounted applicators when they are in use (pets should be brought inside if possible or their cages covered to allow a wider application to be performed).

Beginning August 6, 2001, all tentative spray areas received by citizen's request scheduled for that evening will be listed on the CMMCP phone system after 3:30pm. Please call (508) 393-3055 to access this information.

Pesticide Label:

• Zenivex® E4 Pesticide Label

Safety Data Sheet:

• Zenivex® E4 Safety Data Sheet

Resources:

• Exclusions from Spraying
• EPA FAQs on Pesticides & Mosquito Control