WASHINGTON — The Environmental Protection Agency said today in a “pollinator risk assessment” that imidacloprid, a popular neonicotinoid pesticide, poses a significant risk to honeybees — but it failed to examine risks to nearly 4,000 North American native bees and all other pollinators, including imperiled butterflies, bats and birds.
“You can’t claim to do a ‘pollinator risk assessment’ and really only look at one pollinator, the honeybee,” said Lori Ann Burd, Environmental Health director at the Center for Biological Diversity. “That’s not only cheating on the purpose of this work but also cheating the native bees, birds, butterflies and other species threatened by this pesticide. In fact, many of these other pollinators are even more vulnerable to neonicotinoids than honeybees.”
Today’s analysis indicates that for some crop uses, honeybees can be exposed to imidacloprid at concentrations that negatively affect the health of the hive. But a recent Nature study found that wild bees are more sensitive to the acute toxic effects of neonicotinoids — specifically that neonicotinoid seed coatings reduce wild bee density, solitary bee nesting and bumblebee colony growth. The EPA did acknowledge that bumblebees are affected by the pesticide at much lower levels than honeybees, but it nonetheless failed to properly assess the risk.
In addition, the EPA in this assessment improperly relied on just a single industry-provided study to assess risk to honeybee colonies, despite an abundance of published studies by independent scientists looking at this issue.
“The EPA’s decision to rely on industry-funded research is absolutely unacceptable, particularly when there has been so much research by independent researchers,” said Burd.
While the EPA emphasized honeybee colony risks, its risk assessment found effects on individual honeybees, not on colonies, from most crops.
“This risk assessment, while deeply flawed, does expose the substantial effects on individual honeybees from neonicotinoid treated crops,” said Burd. “However, the EPA refused to make a determination on colony-level risks for specific crops when it had anything less than conclusive evidence on the risks. This flawed methodology caused the agency to dramatically understate the risks of imidacloprid. Also, the colony-level risk assessment only takes into account exposure via nectar, not pollen. So the EPA is analyzing effects on pollinators without even taking pollen into account.”
Bees and other pollinators face myriad other threats, including climate change, genetically engineered crops and monoculture, disease, pests, and habitat loss. Studies show that even low levels of exposure to neonicotinoids, which act as potent neuro-toxins, increases the risk posed by these other threats on weakened honeybees.
Neonicotinoids are a class of pesticides known to have both acute and chronic effects on honeybees, birds, butterflies and other pollinator species, and they are a major factor in overall pollinator declines. These systemic insecticides cause entire plants, including pollen and fruit, to become toxic to pollinators; they are also slow to break down, and thus they build up in the environment. A large and growing body of independent science, including today’s study, links neonicotinoids to catastrophic bee declines. Twenty-nine independent scientists who conducted a global review of more than 1,000 independent studies on neonicotinoids found overwhelming evidence linking neonicotinoid pesticides to declines in populations of bees, birds, earthworms, butterflies and other wildlife.