Scientists now are enabled to work out the reasons of global decline in honey bees by using a new method, which could detect a large number of pesticides in bees. A recent research using that method has found that poison honey bees contain up to 57 different pesticides.
In the Journal of Chromatography A, the team of researchers led by Tomasz Kiljanek of the Department of Pharmacology and Toxicology has reported their process and method of studying, finding out pesticides and metabolites in honey bees.
The population of honey bees in the US and the whole world is decreasing. As approximately 35% of the food consumed in the US comes from crops which are pollinated by honey bees, the lack of this insect might lead to low-quality dinners.
One of the factors contributing to the fall in honey bee population in the US and Europe is colony collapse disorder (CCD). However, the causes and mechanism of CCD has not been explained clearly yet. Many other factors, including pesticides, are suspected of involving in that matter.
As some studies said pesticides were associated to bee deaths, the use of neonicotinoid pesticides has been banned. However, banning one pesticide is not enough to tackle with the problem of bee population decline, the author of new study indicated. It is a hard task to work out which pesticides would be harmful, due to the wide use of so many pesticides today. Harm can also be accumulated over time, or from combined effects.
Kiljanek indicated that even at low levels, due to interaction effects, bees’ defence systems could be weakened by pesticides, becoming vurnerable to viruses and parasites. Hence, researchers are in need of more sensitive and effective ways to detect as many pesticides in bees as possible. Thus, there comes a test for a large number of pesticides in order to point out what has poisoned the bees.
Basing on a system called QuEChERS that is used to detect pesticides in food, Kiljanek and his team has developed their own method to detect pesticides.
Their system uses a combination of mass spectrometry and chromatography. Mass spectrometry is a method to identify and quantify molecules while chromatography is to separate the ingredients of a mixture.
In order to implement that method, researchers has got some difficulties in preparing a sample to analyse without including compounds from the bees. The bee’s body is very complex, and the sample must contain no beeswax, chitin and proteins.
Eventually, researchers have successfully adapted that method and tested poisoned bees for nearly 200 pesticides at the same time, of which 98% are approved for pesticide use in the EU. 70 poisoned bees were investigated and 57 pesticides were found in their body.
Kiljanek commented that those findings are just the first step to deal with the impact of pesticides on honey bees. Their outcomes will improve the knowledge about the influences of pesticides in bee health and provide significant information for other scientists to evaluate the risk from mixed pesticides.