Faced with intense opposition from environmental and community groups, Salt Lake City mosquito-control officials have abandoned their proposal to use military aircraft to spray chemical insecticide.
The controversy, however, has hardly abated.
The city’s mosquito abatement district hoped to save thousands of dollars by enlisting the U.S. Air Force, which would provide a C-130 Hercules transport plane and pilots at no cost, to apply adulticide chemicals over the city’s largely uninhabited northwest quadrant, where these soggy lands meet the Great Salt Lake. While officials remain confident the project would have been appropriate and safe, they cited a preference to working hand in hand with the project’s critics “so that we can all move forward with solidarity towards public health.”
“The negative attention that it has garnered by a very small vocal percentage of the population is not worth the demand on our time/effort and strain on our public relations that we feel are requirements to move forward,” Ary Faraji, the district’s executive director, wrote in an email. “Our mission is to protect public health and enhance quality of life for ALL of our residents. ... We will continue to use the latest technologies, science, and methods to accomplish our mission.”
At a board meeting Thursday, the district officially pulled the plug on the Air Force proposal, but that move did little to reduce opposition to aerial spraying, which the district has done for years and has no plans of abandoning.
Now one group, Utah Physicians for a Healthy Environment, is pressing the district to pause all spraying, from planes and the ground, for two years. It also is calling for an independent and thorough analysis of these chemicals’ impacts on the environment and public health.
“Funding for the study could easily be obtained from the money saved by the [district] by not spraying,” Brian Moench, the group’s president, wrote in an email.
Other organizations opposed to spraying are the Great Salt Lake Audubon and the Westside Coalition, whose concerns focus on the chemicals’ potential impact on the health of the nearby avian and human communities.
District officials contend they apply these chemicals in such low concentrations that they cannot harm people, adding that the applications are timed to avoid harming nontarget insects, especially pollinators.
Moench is not convinced.
“It is long overdue that that practice be completely reevaluated,” he told the district board Thursday. “We made a strong case that adulticide spraying was harmful to public health, specifically neurodevelopment of children, was likely ineffective, and possibly counterproductive in controlling the mosquito population, and was ineffective in controlling [West Nile virus] cases, which are already very low.”
The district’s five-member board includes Dagmar Vitek, the Salt Lake County Health Department’s medical director.
Aerial spraying is only a small part of what the century-old mosquito district does, according to Faraji. Much of its work entails monitoring mosquito populations, testing them for certain disease-causing pathogens, and applying insecticides directly to water where mosquito larvae flourish. The district also raises larvae-eating fish, which are released into ponds and pools.
“Our operations utilize an integrated mosquito management approach, where adulticide applications are a last resort and ONLY conducted when deemed absolutely necessary through our surveillance data,” Faraji said. Aerial applications never occur over neighborhoods and only four took place last year from small planes over the wetland mosquito habitat targeted by such operations northwest of the Salt Lake City International Airport.
In response to the Air Force proposal, the physicians group submitted a 63-page report, titled “Another ‘Downwinder’ Threat to Utahns,” detailing potential dangers posed to human health arising from exposures to insecticides the district uses. Moench argues whatever public health benefits accrue from spraying for mosquitos are offset by the release of toxins into the environment.
“The scientific and empirical evidence is overwhelming that spraying adulticides to kill mosquitoes, especially aerial spraying, is ineffective, and can be even counterproductive, over the long term, and even the short term, to both goals of controlling mosquito populations and preventing West Nile virus,” the report said. “This practice is an institutionalized relic of the 1950s and should be stopped immediately.”
It went on to highlight a link between autism and exposure to pyrethroid, a chemical compound found insecticides used for mosquito control. This chemical interferes with acetylcholine, a neurotransmitter that is critical to memory, attention and learning, and is depressed in the brains of autistic children, according to the report.
“The primary and most consistent human effect of insecticide exposure is neurotoxicity,” it stated. “That is hardly a surprise, given their origin as nerve agent chemical weapons.”
Citing guidance from the federal Centers for Disease Control and Prevention and the Environmental Protection Agency, Faraji rejected the report’s assertions, especially the one about autism. For aerial applications, the district uses organophosphates, an entirely different class of chemical than pyrethroid, according to Faraji.
“The overwhelming weight of scientific evidence does not support any of their claims,” he said. “Aerial spraying is a standard practice in the U.S. that has been thoroughly vetted through the scientific process.”
The district has no intention of adjusting its operations in response the the Utah Physicians report, according to Faraji. At its Thursday meeting, however, the district board did approve a study to be conducted by independent consultant, AQUEHS Corp., to determine where the sprayed insecticides go and to measure their accumulations on the ground.