(Beyond Pesticides, July 11, 2017) South Florida resident Michael Hall, M.D., filed an emergency request in federal court last week to block Miami-Dade County’s continued use of the organophosphate insecticide naled to control mosquito populations. There have been two rounds of aerial naled applications in Miami-Dade this year. Widespread use of the chemical in efforts to control the transmission of Zika last year prompted protests from residents complaining of health effects from the spraying, and calls to focus on less toxic, alternative methods of mosquito breeding prevention and control.
The present use of naled in Miami-Dade is not focused on Zika control, but addressing the native salt marsh mosquito, which does not transmit human diseases, but can be a significant nuisance in shoreline areas. According to WLRN, officials are no longer using naled for Zika control as the mosquito species that carries it, Aedes aegypti, usually stays well hidden under vegetation and shrubbery. A study released last year confirmed that the county’s use of naled did little to reduce mosquito populations. “Naled, a potent organophosphate adulticide applied aerially, produced a transitory suppression in Wynwood but lost efficacy after two or three applications. In Miami Beach, aerial application of naled produced no significant reduction of the Aedes aegypti population,” said Phil Stoddard, Ph.D., Florida International University biology professor and mayor of South Miami.
Miami-Dade is now conducting larvaciding and using backpack foggers with pyrethroid-based insecticides. However, there is no indication that this halt in Zika-focused naled use is anything but temporary, as reports show a recent increase in the number of Aedes aegypti found in the county.
Dr. Hall is alleging that the county has routinely failed to provide residents adequate warning about potential aerial uses of naled, and that it failed to follow federal guidelines for the chemical’s use. The lawsuit also alleges that federal approval of naled poses a health risk, and is asking the court to suspend the use of the pesticide until additional information on its safety can be heard.
“We’re asking, we’re begging, we’re imploring, we’re pleading, we’re really desperate for our community not to be sprayed,” Dr. Hall said to WLRN.
Dr. Hall cites recent studies showing significant risks from the use of naled. In June of this year, an international team of scientists from the U.S. and China found naled to be associated with decreased motor functioning in infants. Last year, Beyond Pesticides sent a letter to EPA citing the inadequacies of its scientific review as outdated and incomplete, leading to significant safety concerns. A 2015 deadline the agency set for a final review decision on residential exposure to naled has still not been met. Meanwhile, reports of massive bee kills, and sick residents continue to be reported in the news.
While reports of Zika-carrying mosquitoes are up, the Centers for Discase Control and Prevention (CDC) removed all travel cautions for Zika infection in Miami-Dade county as of June 2. “We are so open to doing this however we can get it done,” said attorney Cindy Mattson to the Miami Herald. “The point for us is we don’t even have Zika. The CDC took us off the danger [list] and they’re spraying us anyway. It doesn’t make any sense. We felt like it was an emergency to get them to stop spraying.”
Smart community mosquito management focuses on education and source-reduction as the primary means to manage mosquito-borne disease outbreaks. Community residents are encouraged to dump out standing water at least once a week, and effective vector control operations also eliminate standing water sources to the extent possible and, as needed, treats water bodies with least-toxic larvacides like bacillus thuringiensis. Use of mosquito adulticides have been shown to lack efficacy and should only be as a last resort temporary measure when other options have failed and there is an imminent public health threat – never as a regular course of action. Beyond Pesticides’ Mosquito Management program page provides a list of resources that can help individuals and communities safely manage mosquitoes, including information on least-toxic mosquito repellents, bed nets, and proper clothing that can be used to keep mosquitoes safely at bay. Beyond Pesticides produces educational doorknob hangers available for print out or request, which can be used to educate neighbors on the adoption of pesticide-free methods for reducing mosquito populations in communities nationwide.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.