The research was detailed at a scientific briefing in London organized by the Soil Association, Dave Goulson, professor of biology at the University of Sussex specializing in the ecology and conservation of bumblebee, says the new research found that when neonicotinoids are applied to seeds, low concentrations are found in the nectar and pollen of the crop, which are then collected and consumed by bees.
But throughout spring and summer, mixtures of neonicotinoids and other pesticides are also found in the pollen and the nectar of wildflowers growing in arable field margins and hedgerow flowers such as hawthorn, wild rose, blackberries and honeysuckle at concentrations that are sometimes much higher than those found in the crop.
“Indeed, the large majority (97%) of neonicotinoids brought back in pollen to honey bee hives in arable landscapes was from wildflowers, not crops,” Goulson says.
“Both previous and ongoing field studies have been based on the premise that exposure to neonicotinoids would occur only during the blooming period of flowering crops and that it may be diluted by bees also foraging on untreated wildflowers.
“Here, we show that exposure is likely to be higher and more prolonged than currently recognized because of widespread contamination of wild plants growing near treated crops.”
Soil Association policy director Peter Melchett said one in 10 species of Europe’s wild bees is facing extinction, and neonicotinoid insecticides are increasingly seen as contributing to these declines.
“This shocking new research shows that the very wildflowers that were designed to protect bees are actually killing them.” Melchett said.
“The scientific panel agreed pesticides in general, and neonicotinoids in particular, are one of the key reasons why bumblebees and other pollinators are in decline. But the dramatic new issue raised at this briefing is that we cannot save bees while we continue any use of neonicotinoids – the current ban should be extended to all crops.
“The routine, regular use of any toxic chemical or drug is now seen as bad practice and seed coatings like neonicotinoids are just that – used routinely, and long before any problem emerges,” Melchett said.
“This prophylactic use of pesticides should be stopped.”
To combat bee decline, the UK government’s pollinator strategy has focused on creating safe havens for bees by increasing flower habitats next to fields, but Melchett said the new research shows these flowers may be laden with dangerous chemicals.”
The panel concluded that the ban on neonicotinoids should be maintained and more work needs to be done looking at chronic exposure to neonics. It said the regulatory system is flawed and only looks at a limited period of exposure and does not include exposure to chemical cocktails. The panel also called for more large-scale landscape studies.