West Nile spraying harms innocents, too

This is the time of year when backyard gardeners startmaking plans for a crop of healthy organic vegetables to feed themselves and their families. But with the Butte County Mosquito and Vector Control District also making plans—to drench our neighborhoods with pesticides this spring to control the mosquito that spreads West Nile virus—will these backyard crops, in fact, be organic?

And, since the pesticides target insects indiscriminately, will the mosquito’s natural predators (like dragonflies) be wiped out, too? And, will sufficient numbers of pollinating insects survive to pollinate our gardens effectively?

I’ve learned that it’s against federal law for an applicator (such as BCMVCD) to state that a pesticide is “safe.” Yet the BCMVCD has repeatedly said in local newspapers and other media that it only uses “safe, natural pyrethrin pesticides made from flowers.”

To be effective, pyrethrin must be accompanied by piperonyl butoxide (PBO), a chemical suspected of being a carcinogen, a liver and gastrointestinal toxicant, a neurotoxicant, a reproductive toxicant, and an agent adverse to the human immune system. PBO is especially toxic to infants whose liver enzymes are not fully developed, and suspected of being a “hormone disrupter” that can cause breast cancer.

The pesticides that the BCMVCD sprayed Chico with last summer all contained PBO.

Persistent pesticide use on adult, flying mosquitoes doesn’t work because mosquitoes evolve quickly, becoming immune to the poison. With each round of pesticide use, only 40 percent of the adult population is killed, leaving 60 percent to survive and, within 10 days, give birth to a new generation of mosquitoes with an inherited resistance—requiring ever-increasingly toxic sprays to effect another 40 percent kill.

In other municipalities, control of the larval stage of the mosquito has proven to be much more effective. Pesticides are still used, but in smaller and more controlled applications, only when and where needed, instead of ineffectually spraying an entire town. These towns also use other less toxic and more effective alternatives to controlling mosquitoes such as utilizing biological controls, introducing and protecting natural predators (mosquito fish, bats, dragon flies), and eliminating sources of standing water.

Urge the BCMVCD to concentrate its efforts on the control of mosquito larvae and not the ineffective, toxic spraying of adult mosquitoes. No one wants to get West Nile virus, but the prospect of indiscriminately poisoning ourselves and the environment with annual doses of toxic spray poses a threat that’s even worse than the exposure to WNV itself. It seems reasonable to use safer, more effective alternatives.