Thanks to some good traveller friends, researchers were able to accumulate and sample 198 different honeys from every continent except Antarctica for the span of three years (starting 2012).
With these sweet delights, Alex Aebi of the University of Neuchâtel, Switzerland and his team were able to have a global test on honey's neonicotinoid contents. They found that 75% of these have at least one of the five neonicotinoid pesticides, and nearly half of those contained two to five different kinds!
Perhaps more disturbingly, they also found that 48 per cent of these contaminated samples exceeded the minimum dose of neonicotinoid that can cause “marked detrimental effects” in pollinators. “The situation is indeed bad for pollinators,” says Aebi.
“Finding neonicotinoids in honey is perhaps not surprising,” says Christopher Connolly of the University of Dundee, UK, as pesticides have been used widely around the world. “But to find neuroactive levels, in so many samples at many global sites, is shocking.”
And since bees feed on honey to survive winter, this could mean that our buzzing friends are chronically exposed to neonicotinoids. “Recent scientific evidence [even] showed an increased sensitivity to neonicotinoids after frequent or long-term exposure,” says Aebi.
Moreover, the mixture of different neonicotinoids in honeys also spells doom as all can affect various receptor proteins in bees' nervous systems, ultimately affecting their health. Some chemicals can even increase each others’ toxic levels later on, says Connolly. The contamination, however, is still not high enough to affect us.
Unfortunately, there are still no direct evidence on this occurrence as of now which makes it difficult to understand further how neonicotinoids can affect these insects. Nonetheless, this just shows how pesticides affect the environment greatly and that it would be not so long before it directly influences our health.
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