“The fundamental flaw of both the EPA and the PMRA reports (and the whole regulatory system in both countries) is that conclusions are based on registrant submitted data.” Susan Chan, pollination biologist, Farms at Work.
Imidacloprid is being reviewed (it is one of five others neonics. Clothianidin, Thiamethoxam, Dinotefuran, Acetamiprid and Thiacloprid will all get reviewed at a later date) and here is what the PMRA says about this very widely used pesticide:
The residue levels in crop pollen and nectar resulting from seed treatment uses are typically below levels expected to pose a risk to bees at both the individual bee and colony levels.For other applications such as foliar applications (on leaves of crops), potential risk from foliar application varies with application timing. Current label restrictions aid in minimizing risk. In soil applications, a potential risk to bees was identified for some soil treatments. Read more here.
PMRA is evaluating Imidacloprid in cooperation with the Environmental Protection Agency (EPA) in the States. EPA’s press release indicates that imidacloprid potentially poses risk to hives when the pesticide comes in contact with certain crops that attract pollinators.
I was searching the internet for opinions on the EPA review and found this in Mother Jones. Here’s a quote from an article:
The EPA's long-awaited assessment focused on how one of the most prominent neonics—Bayer's imidacloprid—affects bees. The report card was so dire that the EPA"could potentially take action" to "restrict or limit the use" of the chemical by the end of this year, an agency spokesperson wrote in an emailed statement.
Reviewing dozens of studies from independent and industry-funded researchers, the EPA's risk-assessment team established that when bees encounter imidacloprid at levels above 25 parts per billion—a common level for neonics in farm fields—they suffer harm. "These effects include decreases in pollinators as well as less honey produced," the EPA's press release states.It continues:
The crops most likely to expose honeybees to harmful levels of imidacloprid are cotton and citrus, while "corn and leafy vegetables either do not produce nectar or have residues below the EPA identified level."
Meanwhile, the fact that the EPA says imidacloprid-treated corn likely doesn't harm bees sounds comforting, but as the same USGS chart shows, corn gets little or no imidacloprid. (It gets huge amounts of another neonic, clothianidin, whose EPA risk assessment hasn't been released yet.)I checked in with pollination biologist, Susan Chan of Farms At Work. Susan agrees that the PMRA has taken a very strange stance on the imidacloprid issue, “often making definitive statements about lack of risk with no data to hand.”
The biggest imidacloprid-treated crop of all is soybeans, and soy remains an information black hole. The EPA assessment notes that soybeans are "attractive to bees via pollen and nectar," meaning they could expose bees to dangerous levels of imidacloprid, but data on how much of the pesticide shows up in soybeans' pollen and nectar are "unavailable," both from Bayer and from independent researchers. Oops. Read full report here.
Susan highlights that it is important to understand that many of these decisions are based on data submitted by the registrants (ie the chemical companies that want to sell their product) not on data in the open scientific literature. “The fundamental flaw of both the EPA (a 300 page-long report) and the PMRA reports (and the whole regulatory system in both countries) is that conclusions are based on registrant submitted data,” she says.
Susan points out that the big emphasis is now on risk of exposure rather than on the toxicity of these insecticides and the blanket assumption that bees are not at risk to exposure from wind-pollinated plants. "This is in fact untrue: as generalist, opportunistic foragers, honey bees visit a wide variety of wind-pollinated plants for pollen," Susan says. She says that last summer, she personally watched them preferentially collecting pollen in large numbers from ragweed growing among squash plants.
Susan explains that ragweed produces copious amounts of pollen but squash plants produce copious amounts of both pollen and nectar! “These honeybees were obviously making foraging choices that aren't following PMRA's rules!”
What about other, non honey bee pollinators and creatures?
In its report, PMRA says the following:
The honey bee is used in the risk assessment to represent all types of bees and other insect pollinators, although there is mention of native bees.But what about other pollinators and invertebrate aquatic creatures? “Pollinators are just the tip of the iceberg...what about solitary wasps, flies, butterflies, etc., ad nauseum!” says Susan.
"I guess my largest complaint is that although lip service is being given to native bees, there continues to be an appalling lack of data and understanding on the subject. This is especially troublesome because PMRA glibly pronounces that honey bees are an adequate substitute for native bees in toxicity testing. You will understand how absurd this is because honey bees are highly eusocial while 90% or more of native bees are solitary. Furthermore the term "native bee" encompasses 400 species in Ontario alone: These range in size from bees about the size and mass of a grain of rice to bumble bees that are as big as the end of my thumb. I simply cannot accept (based on no data) that all of these bees are properly represented in toxicity testing by honey bees!"
And finally, the other big problem we are facing is the very short submission deadline--we have until December 2016 to supply more data on native bees. Susan plans to be collecting data this summer but it represents a real challenge.
“Perhaps we need to start a serious citizen science data collection project!” Susan concludes….humm. I think she’s onto something.
Thankfully, the Ontario government plans to continue with precautionary measures as it reviews the federal government’s report.
Read the consultation document.
If you would like to comment visit here.
Grain Farmers of Ontario aren't unhappy with the report. They rather like it, and go as far as to say things like the provincial government's policy is not based on science.
"Quite the contrary," Susan remarks. "I would say that the weight of science is leading us to believe that imidacloprid and other neonicotinoid insecticides are indeed very worrisome. "
Read this article here.