25000 Bees Dead in Oregon Parking Lot: How Safe are Pesticides?

A Target parking lot in Oregon became a mass graveyard for bees earlier this week. About 25,000 bumblebees were found dead, some of them still twitching or walking in tight circles on the asphalt, according to The Oregonian. The culprit was a pesticide, bringing into question the safety of their use in the environment.

Bumblebees are crucial pollinators in Oregon. Like honeybees, they help farmers grow everything from apples to cucumbers to watermelon. Yet over the years, these insects have continued to decline. They're being affected by environmental shifts, pesticides and other chemicals that have infiltrated their habitat.

In this case, an improperly applied pesticide may indeed be the culprit for the mass amount of bee deaths. Insects fell out of the 55 blooming European linden trees in the parking lot. These deaths continued into Wednesday as a massive amount of bumblebees littered the lot in addition to a few ladybugs. It turns out that the trees were actually sprayed on Saturday with an insecticide called Safari, according to the Oregonian. However, it will take a few more days to confirm this was the cause of the bee deaths.

Safari is part of the neonicotinoid pesticide family. It's sprayed on a plant so that its leaves, flowers and nectar become toxic to almost all insects. In fact, research at several universities seems to point out that neonicotinoids may be responsible for the devastating colony collapse disorder (CCD), according to Discovery News. This condition has helped wipe out pollinators across the United States as adult bees die off, leaving the colony undefended and unable to survive.

In fact, the European Commissions slapped a two-year ban on insecticides suspected of killing off bee colonies following the findings by the European Food Safety Authority. Despite the fact that neonicotinoids are under intense scrutiny, though, there may be other pesticides out there harming bees.

"These neonicotinoids are just one of hundreds of compounds being used and I would be surprised if it was all down to just these chemicals," said Christopher Connolly, a neuroscientist at the University of Dundee, in a news release concerning the ban of pesticides. He exposed bee brains to several pesticides and organo-based pesticides and found that the nerves spun into hyperactivity and then stopped working completely. The fact that previous tests had actually missed this particular symptom is troubling--yet not completely surprising. The nerve agents effects were missed because safety screens looked to see how many honeybees die after four days exposure.

This latest stretch of bee deaths highlights the importance of properly testing pesticides before placing them on the market-especially when they can cause environmental impacts like the ones see in Oregon.

"There haven't been nearly enough studies of all the pesticides or interactions between them," said Connolly. "Beneficial insects such as ladybirds and bees are exposed to lots of different chemicals and we have a really poor understanding of what it does to them."