New
data unearths pesticide peril in beehives
Cornell University
Honeybees -- employed to pollinate crops during the blooming
season -- encounter danger due to lingering and wandering pesticides, according
to a new Cornell University study that analyzed the bee's own food.
Researchers used 120 pristine honeybee colonies that were placed
near 30 apple orchards around New York state. After allowing the bees to forage
for several days during the apple flowering period, the scientists examined
each hive's "beebread" -- the bees' food stores made from gathered
pollen -- to search for traces of pesticides.
In 17 percent of colonies, the beebread revealed the presence of
acutely high levels of pesticide exposure, while 73 percent were found to have
chronic exposure.
"Surprisingly, there is not much known about the magnitude
of risk or mechanisms of pesticide exposure when honeybees are brought in to
pollinate major agricultural crops," said lead author Scott McArt,
assistant professor of entomology at Cornell.
"Beekeepers are very concerned about pesticides, but there's very little field data. We're trying to fill that gap in knowledge, so there's less mystery and more fact regarding this controversial topic."
More than 60 percent of the found pesticides were attributed to
orchards and surrounding farmland that were not sprayed during the apple bloom
season, according to the study.
McArt said that persistent insecticides aimed at other crops may
be surrounding the orchards. In addition, pre-bloom sprays in orchards may
accumulate in nearby flowering weeds.
"We found risk was attributed to many different types of
pesticides. Neonicotinoids were not the whole story, but they were part of the
story." he said.
"Because neonicotinoids are persistent in the environment
and accumulate in pollen and nectar, they are of concern. But one of our major
findings is that many other pesticides contribute to risk."