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This briefing from the House of Commons Library examines the interaction between bees and a group of insecticides, known as neonicotinoids.

Neonicotinoids have been in the spotlight after a number of studies yielded evidence that they have sub-lethal, harmful effects on bees. However, much of that evidence is contested and the picture emerging from the numerous scientific studies on bees and insecticides is complicated and nuanced.

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.
  • After leaked draft regulations were shared with the Guardian newspaper, it was reported in March 2017 that the EU was preparing regulations to ban the use of neonicotinoids.
  • The NFU applied to use neonicotinoid pesticides on 11% of the oil seed rape (OSR) crop in England in 2017. It was announced in April 2017 that, on advice from the Expert Committee on Pesticides, Defra had refused the applications.
  • An application for an emergency authorisation in 2016 was also refused.
  • In July 2015, the UK Government granted an emergency authorisation for the use of restricted neonicotinoids on OSR seeds after an application from the National Farmers’ Union (NFU).

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 and 2017
  • 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

Bees and other pollinators, such as moths and butterflies, play an important role in natural habitats and food supply by pollinating crops and wild plants.

Pollinators, including bees, are showing declines worldwide but, although the overall trend is downwards, this is not universal and not all species are declining. Some are threatened whilst others are extending their ranges.  The same bee species that are being found to be threatened at EU level are not always the same as those that pollinate commercial crops.

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 has been increasing scrutiny of the harmful, sub-lethal impacts of pesticides in general and neonicotinoids in particular on bees. There are numerous scientific studies on bees and pesticides, but neonicotinoids’ effects are not yet fully understood (and differ among neonicotinoids).  There are gaps in the evidence – some of it is contested and sometimes contradictory and there are disparities between laboratory and field study results.  The methodology of some studies has also been questioned; manufacturers have (broadly speaking) argued that the doses used in some laboratory tests are far higher than bees would encounter in the field and so unrealistic compared to field conditions.

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 it’s 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 can be applied to the seed before sowing (a cheaper method of application) and will be taken up by the whole of the plant including the pollen and nectar.

Clothianidin, imidacloprid and thiamethoxam have been restricted for use at EU level since December 2013 (and there were controls before that).   Imidacloprid was listed as an approved substance on 1 August 2009.  Clothianidin is listed as an approved substance as a seed treatment only when measures have been taken to minimise leakage into the environment.

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 were important for farming and food production and there was no evidence that restricting them helps bee populations. The CPA pointed 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 pests.

The 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. 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 restrictions did the European Commission impose in 2013?

The European Food Safety Authority published an assessment in May 2012. This led the European Commission to restrict the use of imidacloprid, thiamethoxam and clothianidin for two years from December 2013.

Will the EU now ban the use of neonicotinoids?

These restrictions will stay in place until the Commission decides to change them. A review of the evidence was promised after two years – in other words by 2015 – but that was expected to be published in January 2017.  There has been speculation that the EFSA report might not appear until September 2017.

After leaked draft regulations were shared with the Guardian newspaper, it was reported in March 2017 that the EU was preparing regulations to ban the use of neonicotinoids.  Commenting on the leak, the Guardian suggested that, although there was only limited evidence to link pesticide exposure with falls in overall bee populations, the European Commission had decided to act on EFSA’s risk assessments.

 What is the UK government’s stance?

The UK Government did not support the restrictions but has implemented them in full. The Government was reluctant because, in its view, field trial evidence did not merit the restrictions; the Government believed that there had not been sufficient analysis of the impacts of the other insecticides that would be used instead.

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:

  • Woodcock et al (2017) used large field experiments to assess the effects of crop treatment with clothianidin or thiamethoxam on honey bees and wild bees in Germany, Hungary and the UK. They found that neonicotinoids reduced bee species’ capacity to establish new populations in the year following exposure.
  • Baron et al (2017) examined the effects of field-relevant doses of one neonicotinoid, thiamethoxam, on wild queens of four bumblebee species and found that two weeks’ exposure led to a reduction in feeding in two out of four species, with evidence too of effects on ovary development in multiple species of wild bumblebee queens.
  • 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.

In August 2015, FoE sought judicial review of the Government’s decision process to grant the emergency authorisation, arguing that it did not comply with EU law governing such authorisations, but the application was denied.

Unsuccessful applications for emergency authorisations in 2016 and 2017

More recent applications for emergency authorisations have been refused.

In 2016, a similar application from the NFU and the Agriculture and Horticulture Development Board (AHDB, a statutory levy board, funded by farmers, growers and others in the supply chain and managed as an independent organisation) 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).

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.

The ECP considered the application at its meeting on 11 April 2017. In its advice to Ministers, the ECP drew attention to gaps in the information provided by the NFU and also expressed concern about whether the emergency use would be sufficiently “limited and controlled”. The ECP also examined the information submitted about risks to pollinators.

Farming minister George Eustice announced in April 2017 that, taking account of the ECP’s advice, Defra had rejected the applications, as the ECP had concluded that neither met the requirements for emergency authorisation.

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, 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 2016, he again spoke of the need for decisions to be based on the level of identified risk. In February 2017, Lord Gardiner of Kimble argued for an approach based on risk assessment, saying that protection of people and the environment will be the highest priority.

Most recently, George Eustice has reiterated the Government’s commitment to a scientific assessment of risk and has said that pesticides that carry unacceptable risks to pollinators should not be authorised.

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. 

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

The Commons Library debate pack on bees and neonicotinoids

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