Vets, Bees and Pesticides

This may be simplistic, but when an insect is subjected to a battery of pesticides, doesn’t it make sense that their population might suffer?

Since 2003 in North America and Europe the tragedy known as Colony Collapse Disorder (CCD) has been wiping out bees. In Europe, the EPILOBEE project concludes that yearly colony mortality rates between 2012 and 2014 were up to 36 percent; in the U.S. data shows that annual colony losses reported by beekeepers reached up to 45 percent. As in, a lot of our bees are dying every year. Scientists have been unable to pin responsibility to a single source; there seems to be a number of factors thrown into the mix, but not the least of which is pesticide exposure.

Yet even that is complicated. It’s not like there is just a pesticide or two as the culprit ... and the relationship between bees and pesticide is complex, say scientists. But now researchers from the National Veterinary Research Institute in Poland have developed a method for much more detailed analyses of pesticides – they can now analyze 200 pesticides at the same time – and results of their recent study using the method are eye-opening.

"Bee health is a matter of public concern – bees are considered critically important for the environment and agriculture by pollinating more than 80 percent of crops and wild plants in Europe," said Tomasz Kiljanek, lead author of the study. "We wanted to develop a test for a large number of pesticides currently approved for use in the European Union to see what is poisoning the bees."

With so many pesticides currently in use, it's difficult to work out which ones are harming the bees. Certain combinations of pesticides, or their use over time, could affect honeybees in different ways. In order to understand what's really going on, we need to know which pesticides and at what concentration levels are present in honeybees, say the researchers. What they found after investigating more than 70 honeybee poisoning incidents was the presence of 57 different pesticides present in the bees.

"This is just the beginning of our research on the impact of pesticides on honeybee health," said Kiljanek. "Honeybee poisoning incidents are the tip of the iceberg. Even at very low levels, pesticides can weaken bees' defense systems, allowing parasites or viruses to kill the colony. Our results will help expand our knowledge about the influence of pesticides on honeybee health, and will provide important information for other researchers to better assess the risk connected with the mix of currently used pesticides."

Source: treehugger