Now an authoritative, peer-reviewed research undermines the pesticide industry's long-repeated arguments that bees are not being harmed, and adds more pressure on UK and US authorities to follow other countries by introducing bans on the chemicals. Although neonicotinoids have faced bans or restrictions in Germany, France, Italy and Slovenia, regulators in the UK and the US have so far accepted the industry's contention that the toxins were not poisoning bees. The pesticide industry blame parasites and diseases for killing bees, and maintained that the levels of neonicotinoids in pollen were too low to damage their health.
Agricultural crops around the world are dosed with the chemicals to prevent insects from damaging them. But evidence has been mounting that they could be to blame for the "colony collapse disorder" that has been decimating bee populations. The US has been losing one-third of its honeybee hives every year, while beekeepers in Europe say that more than one million bee colonies have been wiped out in France, Germany, Italy and the UK since 1994.
In a new study from scientists at Purdue University in West Lafayette, Indiana. They found neonicotinoids in bees, in pollen, in soil and in dandelions, suggesting that bees could be contaminated in several different ways.
"We know that these insecticides are highly toxic to bees; we found them in each sample of dead and dying bees," said Christian Krupke, associate professor of entomology at Purdue and a co-author of the study. Bees also suffered from tremors, unco-ordinated movement and convulsions, which are all signs of insecticide poisoning. "This material is so concentrated that even small amounts landing on flowering plants around a field can kill foragers or be transported to the hive in contaminated pollen," Krupke said. "It stands out as being an enormous source of potential environmental contamination, not just for honeybees, but for any insects living in or near these fields. The fact that these compounds can persist for months or years means that plants growing in these soils can take up these compounds in leaf tissue or pollen."
Buglife, which campaigns to protect insects, described neonicotinoids as "massively toxic" to wildlife. "All the evidence indicates that this pollution kills bees, moths, hoverflies and other essential pollinator species," said Craig Macadam, the group's Scottish officer. "The government must ban neonicotinoids now before further damage is done to our fragile ecosystems."
"We are facing a global ecological catastrophe in which honeybees, bumblebees and butterflies are being wiped from the face of the landscape in every country where neonicotinoids have been introduced," said Graham White, a beekeeper from the Scottish Borders. "The appalling truth is that we no longer have a credible regulatory system for pesticides in Scotland or the UK. All of the so-called regulators are so symbiotically and financially dependent on the pesticide industry that they have no independent freedom of action."