A new class of pesticides positioned to replace neonicotinoids may be just as harmful to crop-pollinating bees, researchers cautioned Wednesday.
In experiments, the ability of bumblebees to reproduce, and the rate at which their colonies grow, were both compromised by the new sulfoximine-based insecticides, they reported in the journal Nature.
Colonies exposed to low doses of the pesticide in the lab yielded significantly less workers and half as many reproductive males after the bees were transferred to a field setting.
“Our results show that sulfoxaflor” — one of the new class of insecticide — “can have a negative impact on the reproductive output of bumblebee colonies,” said lead author Harry Siviter, a researcher at Royal Holloway University of London.
As with neonicotinoids, sulfoxaflor does not directly kill bees, but appears to affect the immune system or the ability to reproduce.
Foraging behaviour, and the amount of pollen collected by individual bees remained unchanged in the experiment.
The study has been published amid legal challenges and shifting national policies on neonicotinoids, among the most commonly used insecticides in the world.
In April, European Union countries voted to ban three neonicotinoid-based products in open fields, restricting use to covered greenhouses.
Earlier this month Canada followed suit, announcing the phase-out of two of the pesticides widely applied to canola, corn and soybean crops.
Neonicotinoids are based on the chemical structure of nicotine and attack insect nervous systems. Sulfoximine insecticides, while in a different class, act in a similar way.
Unlike contact pesticides — which remain on the surface of foliage — neonicotinoids are absorbed by the plant from the seed phase and transported to leaves, flowers, roots and stems.
They have been widely used over the last 20 years, and were designed to control sap-feeding insects such as aphids and root-feeding grubs.
Past studies have found neonicotinoids can cause bees to become disorientated such that they cannot find their way back to the hive, and lower their resistance to disease.
– Colony collapse –
Other research has shown that crop pests have also built up resistance.
“Sulfoximine-based insecticides are a likely successor and are being registered for use globally,” Siviter noted.
In 2013, the US Environmental Protection Agency (EPA) approved two sulfoxaflor-based pesticides for sale under the brand names Transform and Closer.
Sulfoxaflor is also registered in Argentina, Australia, Canada, China, India, Mexico and a couple of dozen other countries.
Experts not involved in the research praised its methodology and said the findings should sound an alarm.
“This study shows an unacceptable scale of impact on bumblebee reproductive success, after realistic levels of exposure to sulfoxaflor,” commented Lynn Dicks, an Natural Environmental Research Council Fellow at the University of East Anglia.
Conducting such research should be a “mandatory requirement” before pesticide companies bring such products to market, he said.
For Nigel Raine, a professor at the University of Guelph in Canada who holds a chair in pollinator conservation, “the findings suggest that concerns over the risks of exposing bees to insecticides should not be limited to neonicotinoids.”
Fears have been growing globally in recent years over the health of bees.
Pesticides have been blamed as a cause of colony collapse disorder along with mites, pesticides, virus and fungus, or some combination of these factors.
The United Nations warned last year that 40 percent of invertebrate pollinators — particularly bees and butterflies — risk global extinction.
Florida Republicans concoct a new scheme to make it harder for students to vote
Florida Republicans do not want to make voting easy for college students — a demographic that leans heavily Democratic.
Former GOP Secretary of State Ken Detzner, an appointee of Gov. Rick Scott, took that to the extreme in 2014, with an order banning county election officials from setting up any early voting sites on college campuses. Last year, following a lawsuit by the League of Women Voters, federal District Judge Mark Walker struck down that order as an unconstitutional burden on students' voting rights. As a result, some 60,000 people were able to vote early on 11 college campuses in Florida in 2018.
WATCH: Trump supporter arrested for smacking reporter’s phone outside Orlando rally
A Trump supporter was arrested during an altercation with a reporter and another man outside the president's Orlando campaign rally.
Video recorded by an Orlando Sentinel reporter shows a man wearing a red "Make America Great Again" hat and another man outside the Amway Center, where President Donald Trump officially kicked off his 2020 campaign.
The two men appear to be arguing with one another, although the second man also appears to be angry about something that took place inside the arena, when the man wearing the Trump hat notices the reporter recording them with a phone.
The real threat to America isn’t Trump’s ‘deep state’ — it’s Trump’s corrupt state: Robert Reich
Trump has been ramping up his “Deep State” rhetoric again. He’s back to blaming a cabal of bureaucrats, FBI and CIA agents, Democrats, and “enemies of the people” in the mainstream media, for conspiring to remove him from office in order to allow the denizens of foreign shi*tholes to overrun America.
But with each passing day it’s becoming clearer that the real threat to America isn’t Trump’s Deep State. It’s Trump’s Corrupt State.
Not since Warren G. Harding’s sordid administration have as many grifters, crooks and cronies occupied high positions in Washington.