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Mounting Evidence for Neonicotinoid Environmental Impact

Mounting Evidence for Neonicotinoid Environmental Impact

13 April 2015

EU - Evidence for the negative impact of neonicotinoid pesticides on the environment is rapidly increasing, according to a joint report from the European Academies of Science to the European Commission.

The report focuses on research performed since 2012, including laboratory research, greenhouse experiments, field work, and descriptive studies in the field looking at the relationship between concentrations of neonicotinoids in the environment and the presence or dynamics of animal species.

Whilst each of these methods have their shortcomings, the report concludes that the various approaches as a whole show mounting evidence for negative impact on the groups of wild organisms that have an important function in agricultural areas.

Some of the organisms affected fulfil important functions in agricultural areas, for example, the wild pollinators and the predatory insects which can play an important role in the biological control of pests.

These significant negative effects include changes to orientation, food-seeking behaviour and resilience to virus infections and parasites. 

The scientists also concluded that even very low concentrations of neonicotinoids can have a significant impact if they are present in the environment for longer periods.

Over the last few years there has been an intensive public debate on whether it is wise to use neonicotinoids. Much of the discussion has focused on real or alleged effects on the honeybee.

Various studies concentrating on the honeybee have tended to produce conflicting results, which the report points out is due to the difficulty in separating environmental effects on the domestic honeybee from socio-economic effects on beekeepers.

In addition, the exceptionally large size of honeybee colonies gives the species a much greater resilience to the effects of toxic substances than smaller, wild bee species which do not form colonies at all.

The scientists advocate a shift of attention from the honeybee to other species important for pollination or biological control of pests, such as wild bees, hover flies, butterflies, moths, ground beetles and farmland birds. These species have shown a systematic decline in species richness over the last few decades.

The report committee notes that in particular the large-scale, usually pre-emptive, prophylactic use of neonicotinoids in the form of seed coatings leads to unnecessarily high pollution levels in the environment.

Most of the toxic substances in the seed coatings enter the soil within a few weeks.

The report concludes that giving permission to use these substances on a large scale does not coincide with earlier EU policy, as Europe invests a great deal in restoring natural environments and there are now strong indications that neonicotinoid use greatly limits the possibilities for restoration.

Commenting on the new report, National Farmers Union Vice President Guy Smith said: “This research is not new and relies heavily on lab-based studies which are not reflective of what has been seen in the field.

"The motives behind the literature which has been studied are questionable; hence why the NFU continually lobbies for regulations to be based on balanced, sound science – not regurgitation of existing studies when new information is needed.

“The neonicotinoids restrictions have taken away a vital tool in the toolbox of UK farmers. Many farmers across the nation have seen their crops be compromised by cabbage stem flea beetle; a pest which was eating away at our plants before they even surfaced due to the absence of the neonicotinoid seed coating protecting the plant in its first growth stages. Its larvae are now inside many plants causing damage from the inside-out. We are yet to see the potentially destructive impacts of turnip yellow virus infections.

“The irony is oilseed rape is an extremely important crop for pollinators including bees, providing an abundant, early, supply of pollen, and helping to create a varied habitat. Conversely, bees are essential to farmers in helping pollinate their crops. But with pests threatening acres of oilseed rape, it is likely farmers will reluctantly reduce the area of the crop grown or simply choose an alternative crop to grow.

“There is no evidence that the restriction has been beneficial to pollinators and the NFU remains concerned that it is politically motivated and the basis for it has oversimplified issues of pollinator numbers which is subject to multiple pressures such as varroa and habitat loss.”

Further Reading

You can view the full report by clicking here.

TheCropSite News Desk

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