Note to bees: do not stop and smell the roses.
A new study released by the environmental consulting firm Pesticide Research Institute and nonprofit group Friends of the Earth says about half of the garden plants sold at big box stores like Lowes, Home Depot, and Walmart contain neonicotinoids (neonics for short), a pesticide highly toxic to pollinating insects – like bees.
Heather Leibowitz, director of Environment NY, a statewide citizen based environmental advocacy organization, says home gardeners are buying plants, completely unaware that they're laced with poisons.
"Gardeners are putting these in their homes," she says, "and there’s no warning they could actually have a negative effect on bees."
There are no federal requirements necessitating that plants treated with neonics be labeled. Leibowitz says the lack of labels on plants is a big problem. Just imagine, she says, that you’re a bee and all that yummy nectar you’re drinking, and the pollen you’re carrying back to the hive is laced with poison and you don't know it.
For bees, this is akin to a plot twist from a horror film. “The flowers," says Leibowitz, "are killing the bees...They just had a little snack, had a little drink and they’re going back to their hive and they’re poisoning the queen.”
Leibowitz says it’s not just farmers, but home gardeners who also now need to pay attention to pesticides.
Tim Brown, an Associate Scientistis with the Pesticide Research Institute and one of the authors of the new study, gets "super science geeky" when he explains how a neonic pesticide works.
“It targets the nicotinic acetylcholine receptors,” he says.
For all the non scientists out there, those are within the teeny, tiny bee brain. But Brown notes, we humans have a lot riding on the wellbeing of the tiny brains of bees.
"A lot of the foods we enjoy eating," he says, "almonds, apples, blueberries, cherries -- there are a number of crops that are pollinated by bees and if we’re not protecting their health then we’re going to see impacts. Either we’re not going to get the supply that we want or it’s going to be a lot more expensive to get these foods."
Joe Bischoff, Regulatory & Legislative Affairs Director for AmericanHort, a horticultural industry association, says the pesticide question is a thorny one for growers. If we stop using neonics we’ll also have a problem he says. Think of the white fly, or the asian long-horned beetle. Not all bugs, notes Bischoff, are helpful to plants.
“If you throw only one chemical class at many of these insects, they overcome it," he says. "In the long run this is a dangerous situation."
Bischoff says growers are worried about controlling problem insects, but he says we should remember that growers are businesses -- they wouldn’t buy pesticides if they didn’t have to.
And the study, he says, could be flawed. The research was based on the presence of pesticide in plant tissue - like flowers. "Bees don’t consume flowers," says Bischoff, "they consume pollen and nectar."
The pesticide also has a half life, meaning it decays and loses its potency over a certain period of time. Instead of banning neonics outright Bischoff says growers should use it more wisely.
But some big box stores are taking anti-neonic action. BJ’s Wholesale Club says it's working to sell plants that are neonic free and Home Depot will require all its suppliers to label plants that they have treated by the fourth quarter of 2014.
Brown says there aren't a lot of studies that look at how long the toxicity of a neonic lingers. One complication is that different varieties of plants metabolize poisons according to different time frames. A lot, he says, depends on the method of application. When a pesticide is sprayed on the surface of a plant the residue won’t necessarily be broken down by enzymes, but the sunlight can cause its strength to fade. But still, a poison may linger for months or years presenting a harmful dining option for bees.
"We know for a fact," says Tim Brown, that if the pesticides are in the tissue of the plant, "it’s in the pollen and nectar too."