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Commons Library analysis: Bees and neonicotinoids

Published Thursday, March 9, 2017

This briefing concentrates on the interaction between bees and a group of insecticides - known as neonicotinoids - which have been in the spotlight after a number of studies yielded evidence (although much of that evidence is contested) of sub-lethal, harmful effects on bees. In July 2015, the UK Government granted an emergency authorisation for the use of restricted neonicotinoids on oil seed rape seeds in four English counties. A similar application for an emergency authorisation for 2016 was rejected and the NFU has submitted a fresh application for 2017..

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Key points are:

  • The use of three neonicotinoid insecticides - clothianidin and imidacloprid (made by Bayer) and thiamethoxam (made by Syngenta) - has been subject to 2 year precautionary restrictions in the EU since December 2013. This is based on concerns that they have sub-lethal but still harmful effects on bees.
  • The UK Government has implemented the restrictions but did not support them because, in its view, field trial evidence did not support the restrictions. The Government believed that there had not been sufficient analysis of the impacts of the other insecticides that would be used instead.
  • The EU Commission is currently reviewing the restrictions taking into account "relevant scientific and technical developments”. The European Food Safety Authority was expected to complete a review in January 2017, but nothing has yet been made public.
  • The restrictions are not time-limited and will stay in place until the Commission decides to change them.
  • In July 2015, the UK Government granted an emergency authorisation for the use of restricted neonicotinoids on oil seed rape (OSR) seeds after an application from the National Farmers’ Union (NFU).
  • An application for an emergency authorisation in 2016 was refused and the NFU has applied to use neonicotinoid pesticides on 11% of the OSR crop in England in 2017.

This briefing therefore examines:

  • The risks that neonicotinoids might pose to bees and the evidence for those risks (and conversely the risks of not using neonicotinoids)
  • Bee health: why are numbers declining?
  • The UK’s restriction on neonicotinoids
  • The UK emergency authorisation in 2015 and unsuccessful applications for authorisations in 2016
  • How pesticides are regulated at the EU level and in the UK
  • EU Commission restrictions imposed in 2013 and
  • Scientific studies and reviews in recent years and before the imposition of the restrictions in 2013.

In a nutshell

Pollinators, including bees, are showing declines worldwide but, although the overall trend is downwards, this is not universal and not all species are declining.  Where declines in bee health and bee numbers have been observed, a number of factors - such as disease, habitat loss, climate change and pesticides – are thought to have contributed.

There are numerous scientific studies on bees and pesticides, but neonicotinoids’ effects are not yet fully understood (and differ among neonicotinoids).  Although the evidence is not conclusive, the EU, acting on the precautionary principle, took action in 2013 and imposed restrictions on the use of three neonicotinoids - clothianidin, imidacloprid and thiamethoxam. These controls are often spoken of as a ban, but neonicotinoids may still be used in certain situations and so it is more accurate to describe them as restrictions.

The UK government did not consider that the evidence merited this action, but abided by the restrictions, although its granting of emergency authorisations for neonicotinoid use in 2015 prompted concern in some quarters that it might seek to overturn the restrictions.

For policy makers and other concerned bodies, the situation remains contested and unclear: an October 2015 review statement by a group of pollinator experts concluded that the evidence still does not provide a clear steer for policy makers in relation to neonicotinoids.

The European Food Safety Authority (EFSA) was expected to complete a review of available data on the risk to bees from clothianidin, imidacloprid and thiamethoxam, update its risk assessments and report to the Commission in January 2017. Nothing has yet been made public and there has been speculation that the EFSA report might not appear until September 2017.

What do we know about bee health?

In the UK, wild bees and other wild pollinators have declined in number in the last 50 years, with changes in the species reflecting changes in our landscapes. Managed bees in hives, though, are faring better; their numbers in the UK are recovering from large losses due to the Varroa mite in the early 1990s.

Pollinator strategies set out (broadly speaking) to support pollinator populations and enable their survival and success. There are pollinator strategies for England and for Wales and an All-Ireland strategy, as well as one being developed in Scotland, to tackle adverse impacts on bees and other pollinators beyond pesticides.

What are neonicotinoids?

Neonicotinoids are widely-used insecticides. They were developed in the 1980s and 1990s and were the first new class of pesticides for 50 years. They have low mammalian toxicity, which has made them an important means of crop protection. Bayer CropScience and Syngenta are the main producers. Neonicotinoids are systemic, which means that they are taken up by the whole of the plant including the pollen and nectar.

Are neonicotinoids bad for bees?

The Centre for Ecology and Hydrology (CEH) suggested in August 2016 that neonicotinoid use is linked to large-scale and long-term decline in wild bee species distributions and communities. Other, more recent studies are mentioned below.

Manufacturers of neonicotinoids, on the other hand, have generally argued that they are unlikely to be responsible for declining bee health or bee numbers and that the alternatives (such as organophosphates) might pose greater risks. On its Bee Care website, Bayer points to the many factors influencing bee health and bee numbers and maintains that realistic field studies show no harmful effects to bees from neonicotinoids.

Similarly, the relationship between restrictions on neonicotinoid use, crop damage and yields is contested.

The Crop Protection Association (CPA, which comprises 22 companies from the UK plant science industry) responded to the CEH study, arguing that neonicotinoids are important for farming and food production and there is no evidence that restricting them helps bee populations. The CPA points to the links between the decline of wild bee populations and several other factors – especially the Varroa mite.

The NFU in England and Scotland claimed in 2015 that the restriction on neonicotinoids had caused heavy losses through oilseed rape crop (OSR) damage from pestsThe most recent figures, available in the ADAS Final Harvest Report 2016, indicate that yields are down: the national yield estimate for winter OSR was 3.0-3.2 t/ha – an 11-17% decrease on the five year average (3.6 t/ha).  Commenting on the poor harvest and decreasing OSR area, the NFU said in November 2016 that it was reviewing the way forward, as OSR production might be in jeopardy if neonicotinoids remained restricted.

The Humboldt Forum for Food and Agriculture in 2013 (in a report funded by Bayer CropScience and Syngenta) estimated that the overall cost of a ban could be as high as €4.5 billion and, over a five-year period, put one million arable production jobs at risk across the EU.   More recently, Farmers Weekly reported in August 2015 that the restrictions on neonicotinoids had cost farmers £22 million: £7.8 million for alternative chemical use, £11.4 million for applying the chemicals and £2.3 for crop lost and not replanted.

Wildlife and environmental groups take a different view.

In an open letter to the UK government in December 2016, to mark the third anniversary of the restrictions,18 wildlife and environmental groups argued that it was “clear that there is now more than enough evidence to retain the ban and extend it to all crops, and that this is essential to reverse the decline of bees and other pollinators”, although the NFU disputed these claims.  The Wildlife Trusts are calling for an outright ban on neonicotinoids. Friends of the Earth (FoE) also continue to call for a ban on neonicotinoids. In a report published in January 2017, looking in particular at the use of clothianidin on wheat, FoE urged the UK government to “commit to a comprehensive ban now that will apply whatever our future relationship with the EU”. The RSPB continues to be concerned about neonicotinoids’ potential effects on biodiversity.

What does the scientific evidence say?

It is sometimes asserted that neonicotinoids must be harmful to bees, but the picture emerging from the numerous scientific studies on bees and pesticides is more complicated and more nuanced.

Already this year there have been studies published, attempting to shed more light on the interaction of factors such as exposure to neonicotinoid pesticides and bee behaviour and health:

  • Klein et al (2017) found that “even at low intensity levels, many stressors damage the bee brain, disrupting key cognitive functions needed for effective foraging, with dramatic consequences for brood development and colony survival”.
  • LaLone et al (2017) concluded that “sufficient biological plausibility exists to link activation of [nicotinic acetylcholine receptors by neonicotinoids] to colony death.”
  • Schick et al (2017) found that data in a 2013 study of thiamethoxam funded by Syngenta - which had concluded that there was no evidence of detrimental effects and so thiamethoxam posed a “low risk” to bees – had not been sufficiently analysed and so the 2013 study’s findings were both misleading and unacceptable in principle.
  • In preliminary findings from a study reported in Farmers Weekly in December 2016, Dr Penelope Whitehorn at Stirling University found that bees’ ability to produce the buzz needed to shake pollen from crops such as potatoes, tomatoes and aubergines (so-called buzz pollination) may be harmed by neonicotinoids.

In 2015, Botias et al drew attention to the contamination of wildflowers at the margins of arable fields and the associated persistence of neonicotinoids, which would increase bees’ exposure.

UK emergency authorisation in 2015

Even where, as with certain neonicotinoids, use of a pesticide has been restricted at EU level, it is still possible to seek an emergency authorisation for its use if certain criteria are met.

In July 2015, the UK Government (advised by the Expert Committee on Pesticides or ECP) granted such an authorisation to the NFU, after the initial application was refused because it was not sufficiently targeted. The authorisation allowed use of a restricted seed treatment for 120 days in Suffolk, Cambridgeshire, Bedfordshire and Hertfordshire.

A similar application from the NFU and the Agriculture and Horticulture Development Board (AHDB) for 2016 was refused: the two organisations had sought emergency authorisation for products containing neonicotinoid active substances for use as seed treatments on winter OSR to control Cabbage Stem Flea Beetle (CSFB).

Application for emergency authorisations in 2017

Farmers Weekly reported in January 2017 that – because of ongoing problems with CSFB - the NFU had applied to use neonicotinoid pesticides on 11% of the OSR crop in 2017. On the NFU website, the NFU vice-president, Guy Smith, set out the farmers’ case.

What impact might Brexit have?

Concerns about the future of the restrictions have been amplified by the UK’s decision to leave the EU.

In the Brexit white paper published on 2 February 2017, the Government sets out its approach to agriculture, fisheries and food. It confirms that the UK will not be seeking to remain in the Single Market and argues that Brexit presents an opportunity to create a “world-leading” food and farming industry.

Further details of the UK government’s approach to agriculture – and more specifically to pesticide regulation - post-Brexit have yet to emerge but, before the referendum, farming minister George Eustice was reported as saying that the EU's precautionary principle needed to be reformed in favour of a US style, risk-based approach, allowing faster authorisation of pesticides.  In response to a PQ in October last year, George Eustice again spoke of the need for decisions to be based on the level of identified risk. In February 2017, Lord Gardiner of Kimble too argued for an approach based on risk assessment, saying that protection of people and the environment will be the highest priority.

This might therefore indicate that the Government could be minded to take a very different approach to pesticides approval with any opportunity for more UK autonomy, although (obviously) much would depend on the terms agreed on exit. Membership of the EEA (for example) requires adopting some pesticides marketing and approval systems. 

The Commons Library debate pack on bees and neonicotinoids was published for a Commons debate in December 2015, triggered by an e-petition.

Other briefings on farming and environmental issues are available on Parliament’s topic pages for agriculture and nature conservation.


Commons Briefing papers SN06656

Authors: Emma Downing; Gabrielle Garton Grimwood

Topics: Agriculture, Biodiversity, Countryside

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