The worrying discovery was made by a team from the National Veterinary Research Institute in Poland, who used a method more commonly used to detect pesticides in food to analyse poisoned bees for a range of substances. The method, called QuEChERS, can be used to detect up to 200 different pesticides, and by investigating more than 70 honeybee poisoning incidents, they detected 57 different types, the vast majority of which are approved for use in the European Union.
The QuEChERS analysis technique uses liquid chromatography tandem mass spectrometry and gas chromatography tandem mass spectrometry to analyse which pesticides are present in samples of the poisoned bees.
Tomasz Kiljanek, lead author of the study, which has been published in the Journal of Chromatography, said:
“Bee health is a matter of public concern – bees are considered critically important for the environment and agriculture by pollinating more than 80 per cent of crops and wild plants in Europe.”
Combinations of pesticides, levels of exposure and different environments are all factors that can affect bee health. And when so many pesticides are in use, it’s difficult to find out which ones are responsible for harming the bees. But finding out what pesticides are at which concentration levels in bees is vital to understanding the situation, so that measures can be taken in future to ensure their survival.
Kiljanek said: “This is just the beginning of our research on the impact of pesticides on honeybee health.”
“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 current used pesticides.”
Bee decline isn’t entirely due to pesticide use – other factors, like the decline of the UK’s flower-rich grassland, climate change and the spread of diseases have all taken their toll on bee populations.
But when countries around the world are expecting future food security issues due to the decline of pollinating insects like bees, getting to the bottom of the pesticide problem is an important step.