‘Are Neonicotinoids Killing Bees?’ This was the provocative title of a conference held recently in London. Organized by SCI’s AgriSciences group, the conference was attended by EU experts from academia, the crop protection industry, farming community and government agencies, who gathered to hold a balanced and constructive debate about this controversial question. For the participants, pollinator health is of key interest, since bees and other pollinating insects are key contributors to sustainable agriculture as pollinators for many food crops.
Bee health has become an issue of public interest in recent years – receiving plenty of media coverage. Unfortunately, this coverage has been largely focused around individual studies on the alleged impacts of pesticides, and particularly neonicotinoids, and the topic has often gained attention due to sensational headlines or misleading language. Scientific publications on studies performed under field-relevant conditions and showing no effects, mostly remain unnoticed.
Bee health is a complex topic, influenced by multiple stressors. For the honey bee, the parasitic Varroa mite and associated viruses are recognized as a common and widespread threat in Europe and North America. For wild pollinators, habitat loss is a key factor. Despite these facts, pesticides remain the focal point of attention. In 2013, increasing public pressure led the European Commission to restrict certain uses of some neonicotinoid insecticides after the European Food Safety Authority (EFSA) highlighted perceived risks and alleged data gaps for their use in bee-attractive crops.
The aim of the AgriSciences conference was to encourage participants to explore and critically review the data behind these restrictions and new scientific evidence related to the bee safety of neonicotinoids, analyze the impact of alternative control methods and consider options for the future. This by offering well-rounded scientific information to the participants to aid decision-making.
The crop protection industry highlighted the continuous work to prevent any risk to bees from pesticides, through extensive testing, risk assessment and stewardship measures. Crop protection products have to undergo comprehensive ecotoxicological tests before they can be authorized, including numerous in-depth bee safety tests. It was noted that neonicotinoids in particular have been subjected to very thorough and intensive testing procedures ranging from simple laboratory tests to field studies, some of which were conducted over several years under realistic conditions.
“Many field trials from different groups of scientists have proven that crops that have been seed-treated with neonicotinoids do not harm the health of honey bee colonies under realistic conditions,” says Dr Christian Maus, Global Pollinator Safety Manager at the Bayer Bee Care Center, Germany. During his presentation he explained the complexity of field studies and presented the latest results from one of the largest field studies of oilseed rape that has recently been conducted in Northern Germany. The study showed that there were no signs of harm of a neonicotinoid seed treatment in oilseed rape for honey bees, bumble bees and a solitary bee species. “The feedback on our study was very positive. We also discussed many other critical studies and interpreted data, which are often looked at just from a single perspective,” he stated.
Data on neonicotinoids and bees is overwhelming, with scientific publications currently coming out almost weekly, most of them highlighting effects. Most published studies are laboratory-based or otherwise look at exposure scenarios that do not accurately reflect field conditions. A problem with some other studies is that an impact is suggested based on correlation, not causation. The conference participants considered an analogy based on a graph showing levels of autism and levels of organic food sales during a particular time period: though both rose in the same time frame, does this mean that one affects the other? Can correlations have an impact? Politically they can, as learned from the discussion about the neonicotinoids.
Besides what is already known, a number of areas for further research were suggested during the conference which would complement our current knowledge. These included the topic of non-Apis bees; mechanisms behind observed sublethal effects and, moreover, a comparative approach balancing alleged effects of neonicotinoids with those of other, alternatively used chemistries.
Conference attendees learned how the crop protection industry is diligently working to prevent risk from pesticides – including neonicotinoids. A specific point of consideration was how Bayer and other producers of crop protection products have been working intensively with the seed industry to reduce the risk of exposure of pollinators to pesticides, for instance through dust drift that could affect pollinator health during sowing of pesticide-treated seeds. The outcome of these efforts has been a number of effective safety measures including development of new technologies to avoid dust emission such as SweepAir and deflectors, higher quality standards for treating seed and improvements in seed coatings themselves.
An important take-away from the conference was that monitoring data indicates that there is no systematic evidence of a spatial or temporal correlation between the use of neonicotinoids and increased honey bee colony mortality. Conference presenters Norman Carreck, from Sussex University, UK and Peter Campbell, of Syngenta, UK, both highlighted the Defra/MAFF monitoring data on honey bee pesticide intoxication incidents in the UK, indicating no incidents linked to approved uses of neonicotinoids in the last 10 years, a period in which their use as seed treatment increased dramatically along with an almost doubling of oilseed rape hectares during this time.
The importance of seed treatment with neonicotinoids for crop protection becomes clear now that it is no longer readily available. UK farmers indicated trouble combatting aphids and the cabbage stem flea beetle in oilseed rape crops, resulting in an increased use of insecticide sprays with older products.
Summarizing her thoughts following the event, Coralie van Breukelen-Groeneveld, Head of the Bayer Bee Care Center, said, “It has been a long time since an event like this has taken place in Europe, where so many different stakeholders come together and really discuss and exchange on the latest updates regarding bee health from multiple perspectives in a constructive way. What really struck me was all the work that has been done on the safety of neonicotinoids. Like Peter Campbell, I can’t help but wonder what we could have achieved if all the money spent on focusing on pesticides had been invested in finding solutions to the key factors impacting bee health.” Bayer’s Bee Care Program goes far beyond activities related to pesticide safety testing and stewardship for bees. In collaboration with many partners, we contribute to bee health and pollinator research.
To get more information on neonicotinoids, you can download our latest BEEINFOrmed fact sheet “The Bee Safety of Neonicotinoid Insecticides”.
You will find detailed information about our study in northeastern Germany in our BEENOW article “Rapeseed: A Safe Source of Food?”.
In addition, results of the above study have just been made public as a series of articles in Ecotoxicology journal.
In a related article in Forbes, Henry Miller gives “Six Reasons Not To Worry about the Bees”.