In summary, this field research has showed that while rare effects cannot be excluded, under normal circumstances neonicotinoids are not having harmful effects on bees.
It has also circulated an updated assessment of the key evidence about neonicotinoids and bees to ‘help inform national and international considerations of this issue’. It supports the view that the risk to bee populations from neonicotinoids, as they are currently used (in the UK), is low.
The NFU lead on bee health, Dr Chris Hartfield, said: “The Defra study shows that there are still significant question marks over the science and evidence around bees and neonicotinoids. A number of studies have shown that dosing bees in the laboratory with neonicotinoids has harmful effects on their behaviour and life cycles.
"However, this latest Defra research is one of several field studies showing that these harmful effects on bees are not seen under normal field situations. These studies also suggest that laboratory dosing can exaggerate the exposure that bees would experience in ‘real-life’ field situations.
“We need to be careful not to get drawn into a game of ‘research study top-trumps’. Defra’s latest research is one more study, with limitations and flaws like all other studies. However what it does show clearly is that we do not have an adequate understanding of the levels of exposure to neonicotinoids experienced by bees under field conditions. And without that fundamental understanding it is clear that we cannot quantify whether and how harmful the impacts are to bees under field conditions.
“The European Commission has decided to manage the risks identified by EFSA around neonicotinoids and bees by banning the use of these insecticides. The Defra study shows that this precautionary approach by the Commission is neither proportionate nor justified by the current evidence we have available.
“Everyone who works to improve bee health would like a silver bullet and a single target to aim it at. But the reality is that bees continue to face multiple challenges of pests and disease, the fragmentation, degradation and loss of habitats, changing climate, invasive species and chemicals they encounter in their environment. We do not have the evidence to point the finger of blame for widespread declines in pollinator populations at any single factor.”