Bee-harming pesticides in 75 percent of honey worldwide: study

October 5, 2017 by Kerry Sheridan
Bees help pollinate 90 percent of the world's major crops, but in recent years have been dying off from "colony collapse di
Bees help pollinate 90 percent of the world's major crops, but in recent years have been dying off from "colony collapse disorder"

Traces of pesticides that act as nerve agents on bees have been found in 75 percent of honey worldwide, raising concern about the survival of these crucial crop pollinators, researchers said Thursday.

Human health is not likely at risk from the concentrations detected in a global sampling of 198 types of honey, which were below what the European Union authorizes for human consumption, said the report in the journal Science.

However, the study found that 34 percent of honey samples were contaminated with "concentrations of neonicotinoids that are known to be detrimental" to bees, and warned that chronic exposure is a threat to bee survival.

Bees help pollinate 90 percent of the world's major crops, but in recent years have been dying off from "," a mysterious scourge blamed on mites, pesticides, virus, fungus, or some combination of these factors.

"The findings are alarming," said Chris Connolly, a neurobiology expert at the University of Dundee, who also wrote a Perspective article alongside the research in Science.

"The levels detected are sufficient to affect bee brain function and may hinder their ability to forage on, and pollinate, our crops and our native plants."

Neonicotinoids have been declared a key factor in bee decline worldwide, and the European Union issued a partial ban on their use in 2013.

For the Science study, the European samples were collected largely before this ban took effect, Connolly said. Further research is needed to gauge the effectiveness of the EU steps.

Five common pesticides

Bees collect nectar as they pollinate plants, and over time this sugary liquid accumulates into the thick syrup of honey.

To test contamination levels, samples of honey were taken from local producers worldwide, and researchers tested for five commonly used neonicotinoids: acetamiprid, clothianidin, imidacloprid, thiacloprid, and thiamethoxam.

These pesticides, introduced in the mid 1990s, are based on the chemical structure of nicotine and attack the nervous systems of insect pests.

"Overall, 75 percent of all honey samples contained at least one neonicotinoid," said the study, led by Edward Mitchell of the University of Neuchatel in Switzerland.

"Of these contaminated samples, 30 percent contained a single neonicotinoid, 45 percent contained two or more, and 10 percent contained four or five."

The frequency of contamination was highest in the North American samples (86 percent), followed by Asia (80 percent) and Europe (79 percent).

The lowest concentrations were seen in South American samples (57 percent).

"These results suggest that a substantial proportion of world pollinators are probably affected by neonicotinoids," said the study.

'Serious concern '

Our planet is home to some 20,000 species of bees, which fertilize more than 90 percent of the world's 107 major crops.

The United Nations warned in 2016 that 40 percent of invertebrate pollinators—particularly bees and butterflies—risk global extinction.

Experts said that while the findings are not exactly a surprise, the threat posed by neonicotinoids should be taken seriously.

"The levels recorded (up to 56 nanogram per gram) lie within the bioactive range that has been shown to affect bee behavior and colony health," said plant ecologist Jonathan Storkey, who was not involved in the study.

"Scientists showed earlier this year that levels of less than 9 ng/g reduced wild bee reproductive success," he added.

"I therefore agree with the authors that the accumulation of pesticides in the environment and the concentrations found in hives is a serious environmental concern and is likely contributing to pollinator declines."

According to Lynn Dicks, natural environment research council fellow at the University of East Anglia, the findings are "sobering" but don't offer a precise picture of the threat to bees.

"The severity of the global threat to all wild pollinators from neonicotinoids is not completely clear from this study, because we don't know how the levels measured in honey relate to actual levels in nectar and pollen that wild pollinators are exposed to," she said.

The levels of exposure to harmful pesticides may be far higher than what can be measured in honey, said Felix Wackers, a professor at Lancaster University who was not involved in the research.

"This shows that honeybees are commonly exposed to this group of while collecting -contaminated nectar from treated crops or from flowers that have come into contact with spray drift or soil residues," he said.

"The actual level of exposure can be substantially higher, as the samples analyzed in this study represents an average of nectar collection over time and space."

Explore further: Pesticides found in most pollen collected from foraging bees in Massachusetts

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8 comments

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EyeNStein
5 / 5 (4) Oct 05, 2017
Well done Momsanto: Another environment, well trampled for profit.
Tom_Andersen
1 / 5 (2) Oct 05, 2017
Articles titled 'X' detected in 'Y' are useless. What normal people (like editors at Science it seems) is that modern detection methods are so sensitive that they can detect anything in anything. Want to count the plutonium in milk, bird poop in wine, TNT in blue jeans, etc - it's all quite doable.

Its related to the fact that every time you take a breath some of the air in that breath was also breathed by Einstien, Newton, and Socrates.
Da Schneib
5 / 5 (2) Oct 05, 2017
Neonicotinoid insecticides seem to be only part of the problem, and not the biggest part. Varroa destructor mites seem to be the biggest problem bee colonies have. It would be a good idea to reduce neonicotinoid insecticides, and protect colonies from foraging in fields that have been recently sprayed with them, and there are laws and regulations in place about this, but finding something to combat the varroa mites that won't hurt the bees seems to be the big gainer.

Colony collapse disorder seems to be on the wane now that there is attention focused on it.
malapropism
5 / 5 (4) Oct 05, 2017
Articles titled 'X' detected in 'Y' are useless. What normal people (like editors at Science it seems) is that modern detection methods are so sensitive that they can detect anything in anything. Want to count the plutonium in milk, bird poop in wine, TNT in blue jeans, etc - it's all quite doable.

Its related to the fact that every time you take a breath some of the air in that breath was also breathed by Einstien, Newton, and Socrates.

Possibly you didn't read the part of this article that stated,
the study found that 34 percent of honey samples were contaminated with "concentrations of neonicotinoids that are known to be detrimental" to bees, and warned that chronic exposure is a threat to bee survival
or possibly you didn't read the article at all and your post was a reflexive comment based on the title. Whatever the reason, it's clear the words "concentrations, neonicotinoids, detrimental, bees" are important and argue against the veracity of your comment.
rrrander
1 / 5 (3) Oct 05, 2017
It's not the pesticides, it's the opposite. The decline in bee population started AFTER major pesticide bans. It's highly likely parasitic mites that kill bees that were being controlled by the pesticides flourished after the pesticides were discontinued. Bee population declines have been marked in large cities where most of the pesticides bans have been put in place. This is why they really can't pin specifics on this problem where they believe the pesticides are responsible.
Whydening Gyre
not rated yet Oct 05, 2017
It's not the pesticides, it's the opposite. The decline in bee population started AFTER major pesticide bans. It's highly likely parasitic mites that kill bees that were being controlled by the pesticides flourished after the pesticides were discontinued. Bee population declines have been marked in large cities where most of the pesticides bans have been put in place. This is why they really can't pin specifics on this problem where they believe the pesticides are responsible.

Well, they are not doing anything to the bees that took up residence in my fireplace chimney...
howhot3
not rated yet Oct 05, 2017
Neonicotinoid insecticides seem to be only part of the problem, A concern has been expressed that herbicides like Roundup maybe a major cause of bee colony collapse.
larrybeetree
not rated yet Oct 06, 2017
Have seen feral bees survive fine miles away from industrial farming. The lack of cavity structure of large trees world wide from removal has a large part in bee stress. The tidy yards with no rotting wood for other pollinator species to use is a factor. Nature Deficient Disorder is real. Schools for the most part do not teach about natural resources. It is not uncommon in USA to see a person 75 pounds overweight with a Round UP spray bottle hitting a few dandelions. They could be pulling the few "weeds". I say weeds, because half the so called weeds are edible. Yes there are noxious weeds that are nasty to horses/cows. But who knows which ones? Schools need to step up for starters.

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