MIAMI BEACH — Wearing gas masks and holding signs that said “The Cure is Worse Than The Disease,” Miami Beach residents marched outside city hall early Wednesday to protest the city’s aerial spraying of naled, a pesticide intended to kill Zika-carrying mosquitoes.

“If you’re gonna spray, we want a say,” they chanted.

A half-hour later, they did have their say in a city commission meeting where some protesters advanced organic-based alternatives, promoted the use of “essential oils” to fight the insects, and even claimed that the Zika virus does not, in fact, cause microcephaly in infants.

“Regardless of what the [Centers for Disease Control and Prevention] says, there is clear evidence that the link between Zika and microcephaly is very weak,” said Brandon Burke, who identified himself as a member of the South Florida Poison Response Coalition.

His completely false statement drew cheers from the nearly packed chambers.

Suffice it to say, some Miamians seem more concerned about naled than they are about potential birth defects in Zika hot spots. But should they be?

“Why people are wrapped around an axle about it is puzzling to me,” Joseph Conlon, a technical adviser for the American Mosquito Control Association (AMCA), told The Daily Beast, adding that naled has “gone through full vetting, on a number of occasions by the Environmental Protection Agency, and has been deemed to pose no unacceptable risk to humans when used according to the label.”

After news first broke that Miami-Dade County would be spraying naled over the Wynwood neighborhood last month, it didn’t take long for the debate over naled to reach fever pitch in South Florida.

The Miami New Times declared that the pesticide was “banned in the European Union” but the Florida Department of Health disputed that claim, writing in an FAQ that it’s not banned, but rather because “the product has not gone through the registration process to be approved for use, it cannot be used in Europe.” The New Times responded by pointing to a 2012 EU decision to remove naled from the market.

The debate has only intensified as Zika—and aerial spraying—have moved from Miami to Miami Beach. Naled was first sprayed over Miami Beach last Friday, shortly after experts found Zika in trapped mosquitoes in the city, with a second spraying scheduled for this weekend.

Locals in Miami Beach have been quick to point out that exposure to naled can cause health problems, some of them supported by scientific evidence, some not.

For example, when Dr. Peggy Honein, chief of the birth defects branch of the CDC, informed the protesters Wednesday morning via teleconference that Zika can cause microcephaly, one shouted back, “So can pesticides!” The link between pesticides and microcephaly has been debunked but a popular anti-vaccine website continues to promote the false association.

That’s not to say that there aren’t good reasons for Miami Beach dwellers to be a little wary of naled. It is toxic after all and, in high enough quantities, it can lead to a wide array of negative symptoms in humans such as vomiting, diarrhea, and dizziness. In large concentrations, it can also harm bees and other wildlife. Even Conlon is willing to concede that “one can never say that one of these pesticides is safe” given the possibility of accidental misuse.

But Conlon and other experts want the public to know that the quantities in which naled is being sprayed should not be a cause for concern—especially when faced with active local transmission of a mosquito-borne illness that causes birth defects. As of Tuesday, Florida had reached 70 local Zika cases.

The Environmental Protection Agency (EPA) believes that “naled can be used for public health mosquito control programs without posing risks to people,” even assuming that some toddlers would eat “some soil and grass” after spraying. And the CDC resource on naled emphasizes that the concentration sprayed amounts to about “two tablespoons” for an area the size of a “football field.”

“This small amount does not pose a health risk to people or pets in the area that is sprayed,” the CDC notes.

According to the CDC, naled has been applied to “an average of approximately 16 million acres of the continental United States annually” since the 1950s and it has been used frequently in the aftermath of hurricanes to control mosquitoes.

But this information is of little comfort to some of the Miami Beach residents who showed up at Wednesday’s meeting. One protester interrupted Dr. Honein’s comments on naled to allege that “the CDC is profiting from the pesticide.” Others mumbled “bullshit” under their breath as she spoke.

Sadie Kaplan, who showed up at the protest with her baby daughter, told The Daily Beast that, as a mom, she is “for sure” more worried about naled than she is about Zika.

“I think they went to the extreme,” she said. “It just feels very political and money-driven.”

Mosquito control experts, however, are not eager to conduct aerial spraying. Applying naled from the air is a measure reserved for special circumstances; according to the CDC, it is “the most effective method when large areas must be treated quickly.” And officials do not want to experiment with less-proven methods when costly Zika-related birth defects are on the line.

“I can assure you that the folks from CDC and the folks from the mosquito abatement district in Miami are not purposely opting for naled aerial spray, because it’s expensive and it could be dangerous,” Conlon told The Daily Beast, citing the risk of a low-flying plane crash. “But they’re forced to do it because of the circumstances.”

At the city commission meeting, Miami Beach Mayor Philip Levine tried to relay this same assurance to the protesters, telling them that “no one on this dais wants aerial spraying.”

That didn’t stop the theories about the city being in the pocket of Big Pesticide from swirling around the room. Ultimately, as WFOR reported, the protesters were successful in persuading the commission to pass a resolution encouraging Florida to look into other methods for killing the Aedes aegypti mosquitoes that are transmitting Zika in Miami.

According to Conlon, Florida won’t find anything more effective than naled. And if Miami Beach residents truly want to stop the spraying, he says, they should go home and drain the containers of water in their own backyards.

“If they don’t want naled being sprayed from the sky—[and] they have to because they’ve got mosquitoes all over the place—they should get on the wagon and get rid of the places that breed these mosquitoes so we don’t have to use naled from the air.”