An 88-year-old Kern County woman became the first confirmed death from the West Nile virus in California this year, just days after the State Water Resources Board widened the ground game against its mosquito carriers.

Controversial aerial spraying has already begun, the earliest in the year it started since 2005. The pesticide spraying is governed by U.S. Environmental Protection Agency limits, but has been challenged by environmentalists who don’t think it is safe.

“The chemicals they are using are not benign,” John Wargo, an environmental health professor at Yale University, told the Huffington Post. “They are both known to be toxic by different routes.”

Sacramento County officials disagree and consider the pesticides so safe, they don’t tell residents to take precautions when the spraying begins. “Generally, there is no need to relocate or stay inside,” said Luz Rodriguez, a spokesperson with the Sacramento-Yolo Mosquito and Vector Control District. “If it makes people feel more comfortable, they can close windows or cover furniture. But there's no list of specific recommendations.”

A decision was made this year to add an organophosphate, Dimbrom, to the spraying regimen. Its manufacturer lists it as a possible carcinogen and non-profit Organic Sacramento Director Kim Glazzard calls it “pretty bad stuff.”

“You're spraying poison over thousands of people for the potential of maybe helping a handful of people, Glazzard said. “And kids are especially susceptible.”  The other chemical is Anvil, a synthetic pyrethroid that can affect hormones in very small amounts. Anvil gets a boost from the use of piperonyl butoxide, a chemical that can disrupt brain development in the womb.     

Some opponents of spraying hope the easing of ground treatment restrictions will reduce the need to go airborne. But the ground assault on larvae is not without peril and controversy as well. A federal court ruled in 2009 that pesticide use by mosquito districts had to meet restrictions of the Clean Water Act.

The federal Centers for Disease Control and Prevention considers ground treatments more effective than aerial spraying for eliminating mosquitoes.

All of that leaves the state juggling its reverence for the Clean Water Act, its fear of the virus spreading and its reluctance to spray pesticides over vast swaths of territory, while working with federal authorities who aren’t always on the same page.

Ten people have been reported infected with West Nile in California this year; 240 nationwide. Last year, 159 people in the state were infected and nine died.

–Ken Broder

To Learn More:

First West Nile Death in the State This Year Is Elderly Kern County Woman (by Shirley Jahad, KPCC)

First Case of West Nile Virus Reported in Los Angeles County (by Melissa Leu, Los Angeles Times)

California Lifts Rules That Curbed Anti-Mosquito Ground Treatments (by Cynthia H. Craft, Sacramento Bee)

West Nile Spraying: Are Pesticides Leading to Toxic Exposures? (by Lynne Peeples, Huffington Post)