A new problem has hit for families trying to grow vegetables at home: mosquito spray. More and more of my neighbors are having their yards sprayed for mosquitoes. The spray drifts into other yards when there is any breeze. The technicians usually face the neighboring property as they blast plants at the borders, spraying 20 feet or more onto property that was not supposed to be sprayed. Vegetable gardens, laundry, pets, fish in ponds, solar cookers, and even children can all come into contact with the spray. Ironically, even mosquito predators are killed by the spray, which makes the problem worse.
Read on for what this means for birds and what the toxic ingredient in many sprays does. Mosquito spraying is a big local issue that calls for personal action, new regulations, and more research as we try to create sustainable communities. Find out about a less-harmful alternative and other steps you can take below.
Mosquito Spray, Insect Decline, and Birds
Science Magazine asks this week Where Have All the Insects Gone? Scientists don’t have all the answers yet, but suspect neonicotinoid pesticides used on non-organic crops and loss of habitat. A yard sprayed with mosquito spray is a lost habitat for mosquitoes, butterflies, bees, and more. A friend in Virginia told me she had noticed that there were no insects in her community vegetable garden this year, a big change. She said that a man who runs a local birdhouse project reported finding birdhouses full of birds who had starved to death. No insects, no insectivores.
An Illusion of Safety
I was surprised when a neighbor said that Mosquito Authority told her its spray only killed mosquitoes. At the time (summer 2016) Mosquito Authority website said:
Our technicians go through extensive training in the proper application process with an emphasis on avoiding application to beneficial insects like honey bees…. So as much as we love honey bees, we love our children more. And as much as we want to protect beneficial insects, we can’t do so at the expense of performing the best mosquito control possible.
That language is now gone, replaced by:
As a result, many of these same people are implying (and in some cases flat out accusing) pest control companies like us of killing off the honey bees. We’ve researched it. We could list all the facts, figures and research we’ve found. But the truth is, we are perfectly willing to leave that argument to those who feel compelled to argue.
Warning: you might feel as “compelled to argue” as I do after reading the studies below.
I called the local Mosquito Authority to check on the active ingredients in their spray. The person I spoke with said the active ingredient is Bifenthrin 7.9. That’s a synthetic pyrethroid that kills many insects by altering nerve function and causing paralysis. He assured me that it was not harmful to children or pets.
The EPA has determined that developmental toxicity studies (DNTs) previously required for pyrethroid insecticides do not adequately characterize potential susceptibility of the young.
Scientific Studies Show Danger of Mosquito Spray
Bifenthrin Toxic to Fish and Bees, May Cause Cancer in Humans
The National Pesticide Information Center says we may be exposed to bifenthrin if we “touch it, eat it, or breathe it in.” You may not put random things into your mouth anymore, but toddlers do. Exposed pets may experience vomiting, diarrhea, partial paralysis, and depression. It is highly toxic to bees, fish, and small aquatic organisms.
Bifenthrin is Highly Toxic to Bees, But “Sublethal” Doses Bad Too
Lately more attention has been given to sublethal doses because, although they might not kill an adult bee outright, they can have serious consequences to the survival of young bees and to the future of the whole colony. Imagine a human who is poisoned enough to have brain damage but not enough to die. That would be a “sublethal” effect…. The researchers found that in honey bee colonies exposed to sublethal amounts of these pyrethroids, the queens didn’t lay as many eggs, the number of eggs that hatched was far fewer, and the number of hatchlings that made it to adulthood was even fewer. Since the honey bee life cycle—from egg to adult worker—is just 21 days, you could go from a very strong hive to a very weak one in less than a month.
More Peer-Reviewed Journal Articles on Bifenthrin
In case you don’t yet feel “compelled to argue,” here are a few more scientific articles about the active ingredient in mosquito spray.
- Effect of subacute poisoning with bifenthrin on locomotor activity, memory retention, haematological, biochemical and histopathological parameters in mice.
- Multilevel evaluations of potential liver injury of bifenthrin
- The effect of bifenthrin on the dopaminergic pathway in juvenile rainbow trout (Oncorhynchus mykiss).
What Can You Do To Avoid Mosquitoes and Not Poison the Planet?
Some of my neighbors have switched to an organic garlic spray that kills mosquitoes on contact but then just repels them for several weeks. The bugs evidently have a keen sense of smell. My neighbors say their yards smell a little like pizza for an hour, then they don’t notice it. Mike at Gardens Alive discusses garlic spray for mosquitoes and two non-toxic personal sprays. Toxic Free NC recommends using lotions or creams instead of sprays to avoid breathing in harmful substances.
Better yet, invite birds to eat your insects. Even birds who eat seed feed insects to their babies. Remove the standing water that they need to breed, too. Check your gutters and remove any water traps like old tires or saucers under potted plants. Change the water in birdbaths every week.
We should urge mosquito companies to act as good citizens, but my interaction with them over the past few years leads me to think that won’t be enough. We should urge legislators to adopt new laws that require:
- Notifying neighbors of the spraying schedule so they can keep their pets inside, not hang out laundry that day, and take other precautions.
- Spraying in a way that minimizes drift, such as spraying along the property line instead of across it. Spraying should not be done when it’s breezy out.
- Protecting the technicians, who are exposed to high levels of spray as they work.
What’s your experience been with mosquitoes and mosquito-spraying companies? Please log in and share your comments below. May you have a bite-free summer!