By Lily Smith
The first global honey survey has been conducted by soil biologist Edward Mitchell and his team at the University of Neuchâtel in Switzerland recently, through the means of testing honey in order to find out the extent to which honey bees and other pollinators are exposed to the harmful pesticide of Neonicotinoids.
Neonicotinoids as a pesticide became popular in the 1990’s, as it was discovered that they attacked the central nervous system of insects but did not have the same effect on humans. However, neonicotinoids have previously caused controversy as studies show that the pesticide not only harms pests but pollinators as well.
Mitchell and his team requested that family and friends send them local honey samples from their homes and vacation destinations around the world. Through this method of crowdsourcing, they managed to collect 198 samples from various locations.
The study found that three out of four of the honey samples contained at least one of the five commonly used neonicotinoids. Mitchell states that “on the global scale, contamination is really striking”, as traces of the pesticide were found even on remote islands with very little agriculture.
The study also found that 86% of North American honey samples contained at least one of the five popularly used neonicotinoids, as did 57% of South American honey samples. Most shockingly almost half of all samples contained more than one type of neonicotinoid, suggesting that bees often forage at multiple sites where neonicotinoids are in use.
There has been debate about whether the use of neonicotinoids is contributing to the decline of pollinators. This said farmers and pesticide manufacturers claim that parasite infection and habitat loss have bigger impacts and are the main causes for the decline.
Research shows that parasitic mites have had serious effects on the population of pollinators. Studies suggest that since the arrival of the parasite Acarapis woodi in 1981 bee colonies in the United States have declined by 39%. Extended research has also been conducted on the effects of habitat loss on the population of pollinators, with studies finding that a lack of natural habitats is putting a large strain on the resources of pollinators. This said it is clear that all of these factors are playing a role in the ever-declining population of pollinators.
Mitchell suggests that the results from the study show that honey bees and therefore most likely other pollinators are being exposed to levels of neonicotinoids that have been proven to harm insects in previous studies. This said these concentrations are below a level that would harm humans if consumed.
Main concerns about the effects of neonicotinoids have focused on European honeybees, that which have been spread across the world to act as pollinators. This said, Geraldine Wright, an insect neuroethologist of Newcastle University states that native pollinators are just as vulnerable to the harmful pesticide. Bumblebees and sweat bees, for example, live in much smaller hives than honeybees and therefore are more vulnerable, as just a few foragers could spread contamination throughout the colony.