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Neonicotinoids and bees; what is the fuss all about?

May

07

When I was first asked to support a ban on neonicotinoid insecticides, I was very sceptical. I’d previously been asked to sign up for campaigns claiming that bee declines were due to mobile phones, GM crops, overhead power lines, and various other eccentric or implausible notions. However, a review of the science suggested that there was something worth investigating, and for the last two years I seem to have had time for little else.

The issue has focussed largely on harm these chemicals might be doing to bees, both domestic honeybees and wild pollinators such as bumblebees. I’ll focus on bumblebees here, for they are the subject of my particular expertise. Neonics are widely applied as a seed dressing to crops such as oilseed rape, and being systemic they spread through the plant tissues into the nectar and pollen. They are highly toxic to insects; for example the “LD50” (the dose that kills half of test subjects) in honeybees is about 4 billionths of a gram. To put that in context, 1 gram – little more than the weight of a sachet of salt – would provide an LD50 to 250 million honeybees, or roughly 50 metric tonnes of bee. They are neurotoxins, binding to neural receptors in the brain and causing swift paralysis and death.

Until recently, there had been few studies of neonics and bumblebees, all small scale and nearly all performed in cages or glasshouses. Taken together, they seemed to suggest that exposure to very low levels of these chemicals, such as might occur when a bee fed on a treated oilseed rape crop, was not sufficient to kill many bees, but it seemed to affect their behaviour, particularly their ability to learn, gather food, and navigate. These are not impacts that are assessed by any of the safety tests by which pesticides are judged (although there are plans to introduce such tests in Europe in the very near future). They are also impacts that are likely to be much more important in the field, when bees naturally perform astonishing feats of navigation and learning when gathering food from flowers. It seemed to me, and to a number of other researchers around the world, that there was a need to study what impacts these sublethal affects might have on bee colonies in natural situations.

To investigate this, we exposed bumblebee nests to the concentrations of neonics found in the pollen and nectar of oilseed rape for two weeks, and then placed the nests out in the field to see how they fared compared to control nests. Over the following 6 weeks the treated nests grew more slowly, and ultimately produced 85% fewer new queens. Since our study, work from other labs has confirmed that field-realistic doses greatly reduce pollen collection in bumblebee workers, potentially explaining why our treated nests performed poorly. It has also been found that concentrations of neonicotinoid as low as 1 part per billion (ppb) in their food cause a drop in egg laying in bumblebees of 30%. Considerably higher concentrations than this have been found in pollen of treated crops (the typical range in pollen is about 1-10 ppb, although 50 ppb has been found in lucerne pollen, and over 100 ppb in melon pollen).

For bumblebees, the evidence so far is convincing and coherent; exposure to levels of neonic commonly found in crops have profound impacts on colony success. The only study which apparently contradicts this was recently placed online by Defra, a report describing a study they conducted in 2012 in which they attempted to repeat our work but with the pesticide exposure phase of the experiment occurring in the field. They placed bumblebee nests next to the only untreated field of oilseed rape they could find, or next to one of two other fields treated with two different neonics, and they followed the colonies over time. Unfortunately they had no replication – just one field per treatment – and, disastrously but interestingly, the control nests all became contaminated with neonics. The summary of this report claims the study shows no clear effect of neonicotinoids on bumblebee colonies; hardly surprising, given the absence of any controls – and hardly the sort of convincing evidence one would wish government to base its policies upon. It is also not really true – in fact there was a highly significant negative relationship between neonicotinoid levels recorded in each nest and how well the nest performed, but the authors removed this relationship by “taking out outliers” – by which they mean removing the nests that received the highest exposure (which also happened to be the nests that performed most poorly) from their data set and then re-ran the tests.

Perhaps the most valuable lesson to be learned from this work is that bumblebee nests placed into the English landscape become contaminated with multiple types of neonic, even when on farms where none are used. Many of the nests had concentration of neonic higher than 1 part per billion, and most had detectable levels of at least two different neonics.  Bizarrely, the results suggest that bumblebees have a particular predilection for the neonic thiamethoxam, for the control bees seemed to have ignored the untreated rape field right next to their nests and flown a long way to find a thiamethoxam-treated crop.

While the debate has focussed heavily on bees so far, there are broader issues to consider. Neonics are very persistent in soils, and evidence has recently emerged that they accumulate over time; a study in East Anglia performed by Bayer in the 1990s found concentrations up to 60 parts per billion in soil after 6 years of annual use. This is likely to be enough to have profound impacts on soil life. It has also emerged that they get into field margin vegetation, and into streams and ponds. A concentration of just 0.6 parts per billion is enough to kill mayfly nymphs. It may be that, while focussing on bees, we have missed the bigger picture. 

 

The economics

A common argument in favour of neonics is that they provide huge economic benefits, and that the alternatives are worse. A glossy document produced by the “Humbolt Form” (funded exclusively by the agrochemical industry) in early 2013 claimed that a ban on neonicotinoids would cost the EU 17 billion Euros and 50,000 jobs. However, the hard evidence for these claims seemed to be lacking. Indeed, the evidence that neonicotinoids are important for crop production is surprisingly difficult to find. Studies from USA show that yields of soya bean do not benefit at all from neonic seed dressing, despite their application being standard practice. Sadly, similar experiments in the UK have not been conducted. Since farmers get most of their agronomic advice from companies that supply pesticides, it is reasonable to suppose that a good proportion of UK pesticide use may be unnecessary.

 

Whatever happened to IPM?

When I was at University in the 1980’s, I read Rachel Carson’s Silent Spring, and was taught about the terrible mistakes made in agriculture in the 1950s and 1960s when indiscriminate use of persistent, broad-spectrum insecticides, and an abandonment of traditional cropping practices such as rotations led to huge pest outbreaks. The pest insects had all become resistant, while their natural enemies had largely been eradicated. As a result, an approach called Integrated Pest Management (IPM) had been developed, and we were taught that this was the future of pest control. IPM is predicated on minimising pesticide use: farmers monitor their crop pests, and only take action when necessary; they encourage natural enemies as far as possible, use crop rotations and other cultural controls to suppress pests, and only use the insecticides as a last resort. Even then, they avoid those that persist in the environment.

Whatever happened to this philosophy? Why are we now applying pesticides prophylactically to more or less all crops? Did we learn nothing from our past mistakes?  

 

The politics

The EFSA spent 6 months evaluating all the evidence, and concluded that current use of neonics poses unacceptable risks to bees. The UK’s Environmental Audit Committee (a group of MPs) agreed. Numerous NGO’s, including the RSPB, who are normally very cautious, also agree. Even the WI support a ban. What was once a radical stance is now where the vast majority of informed opinion lies; on 29 April the EU member states voted for a 2 year moratorium on use of the three most-commonly used neonics on crops visited by bees.

The UK voted against the ban, with Chief Scientific Advisor Sir Mark Walport saying that everyone else had misinterpreted the evidence. He also argued that applying the precautionary principle would lead us to continue using neonicotinoids, an argument that few of us could follow.

 

What Next?

The moratorium is only for two years, yet we have clear evidence that it will take far longer than this for neonicotinoids that have accumulated in soils to break down. In any case, they are still being widely used, on winter wheat for example, and some types of neonic are not included in the ban.  So it is unlikely that we will see the benefits of the moratorium in rebounding bee populations any time soon. In any case, there seems to be no plan to actually monitor bee populations, so even if they did recover it is not clear how we would know.

What will farmers do without neonics? It is hard to say. It would be nice if they returned to an IPM approach, but with their main / only source of advice being from people with a vested interest in selling chemicals, this seems unlikely. 

 

Have we solved the bees’ problems?

I’m afraid the answer is an emphatic NO. Bees have been declining for many decades, and much of their decline has been due to loss of flower-rich habitat, which has been exacerbated by the arrival of non-native diseases, and by widespread use of pesticides. We have taken a step to reduce (but not remove) their exposure to some brands of one type of pesticide, for two years. That is nowhere near enough. If we want to ensure healthy populations of honeybees, bumblebees, and other wild pollinating insects upon which we depend for our crop production, and more generally if we wish to support the healthy, diverse ecosystems upon which our future health and wellbeing depends, then we need to find ways to produce food in a sustainable way which incorporates the needs of biodiversity. At present we are failing to do this.

 

Dave Goulson's research lab website

 

Does anyone remember Rachel Carson? More on pesticides and bees...

Jan

15

As part of a project to study impacts of pesticides on bumblebees, we have recently been surveying what chemicals the local farmers in East Sussex use each year. Perhaps I was naive, but I found the figures to be astonishing. Below, I’ve pasted a list of the chemicals applied to two fairly typical fields, one with winter oilseed rape, one with winter wheat, in a single growing season (2012/13). For both crops, it is a very long list.

I should stress that these are perfectly normal farms; not especially intensive, situated on the edge of the South Downs, an area of gentle hills, hedgerows and wooded valleys. Beautiful, rural England; Constable would have liked it here. But let’s look at it from a bee’s perspective, focussing on the oilseed rape, since this is a crop they will feed on when it flowers:

Firstly, the crop is sown in late summer with a seed dressing containing the insecticide thiamethoxam. This is a systemic neonicotinoid, with exceedingly high toxicity to bees. We know it is taken up by the plant, and that detectable levels will be in the nectar and pollen gathered by bees in the following spring. In November, despite the supposed protection of the neonicotinoid, the crop is sprayed with another insecticide, the charmingly named Gandalf. What harm could the wise old wizard possibly do? Gandalf contains beta-cyfluthrin, a pyrethroid. Pyrethroids are highly toxic to bees and other insects, but there should be no bees about in November so that is probably OK. The following May, when it is flowering, the crop is sprayed with another pyrethroid,  alpha-cypermethrin. Less than three weeks later, the crop is blitzed with three more pyrethroids, all mixed together, a real belt-and-braces approach. Why use one when three will do? The crop is still flowering at this point (it was a late year), and would be covered in foraging bumblebees and other pollinators.

In between, the crop is also treated with a barrage of herbicides, fungicides, molluscicides and fertilizers – 22 different chemicals in total. Most of these may have little toxicity to bees in themselves, but some, such as a group of fungicides (the DMI fungicides), are known to act synergistically with both neonicotinoids and pyrethroids, making the insecticides much more toxic to bees. On the final application date, when the crop is flowering, one of these fungicides (prothioconazole) is added to the tank mix with the three pyrethroids. Any bee feeding will be simultaneously exposed to the three pyrethroids, the thiamethoxam in the nectar and pollen, and a fungicide that makes these insecticides more toxic.     

We don’t know what impact all of this really has on them. The safety tests generally expose test insects to just one chemical at a time, usually for just 2 days, but in reality they are chronically exposed to multiple pesticides throughout their lives. The fact that we still have bees in farmland suggests that they must be pretty tough. More broadly, we don’t know what impacts all of this has on other pollinators, or wildlife in general. Industry would tell us that all is well. They would also tell us (and the farmers that they advise) that all of these applications are vitally important parts of crop production, and that without them food production would collapse. I have my doubts. Is this really how we want to see the countryside managed? Do we really want to eat food produced this way?

I think I might head home early and finish digging over my veggie plot. At least I can control what goes into that.  

[PS If you find this blog of interest, please share it with your friends using the buttons below right] 

Winter Oilseed Rape

Date

Type of compound

Brand name

Active ingredients

Application method

25/08/2012

 

Insecticide and fungicide

Cruiser

280 g/l thiamethoxam, 8 g/l fludioxonil and 32.3 g/l metalaxyl-M

Seed dressing

Herbicide

Shadow

Quinmerac, Dimethenamid-p, Metazachlor

Spray

Herbicide

Dictate

480g/litre bentazone as sodium salt in the form of soluble concentrate

Spray

Fungicide

Fiddle

Clomazone

Spray

08/09/2012

Molluscicide

Tds Major

Metaldehyde

Slug pelleter

12/09/2012

Herbicide

Shadow

Quinmerac, Dimethenamid-p, Metazachlor

Spray

10/10/2012

Fungicide

Crawler

Carbetamide

Slug pelleter

05/11/2012

Fungicide

Genie 25

Flusilazole

Spray

Insecticide

Gandalf

Beta-cyfluthrin

Spray

16/02/2013

Fertiliser

Double Top

Ammonium Sulphate and Ammonium Nitrate

Fertiliser spreader

Fungicide

Crawler

Carbetamide

Slug pelleter

Herbicide

Pilot Ultra

Quizalofop-P-ethyl

Spray

10/04/2013

Fertiliser

Nitram

Ammonium nitrate

Fertiliser spreader

22/04/2013

Fertiliser

Nitram

Ammonium nitrate

Fertiliser spreader

17/05/2013

Fungicide

Filan

Boscalid

Spray

Fungicide

Flanker

Picoxystrobin

Spray

Insecticide

Alert

Alpha-cypermethrin

Spray

05/06/2013

Fungicide

Propulse

Fluopyram, Prothioconazole

Spray

Insecticide

Hallmark Zeon

100 g/l lambda-cyhalothrin and 1,2-benzisothiazolin-3-one

Spray

Insecticide

Gandalf

Beta-cyfluthrin

Spray

Insecticide

Mavrik

Tau-fluvalinate

Spray

  

Winter wheat

20/09/2012

Insecticide and fungicide

Redigo Deter

50 g/L (4.3% w/w) prothioconazole and 250 g/L (21.4% w/w) clothianidin

Seed treatment

28/09/2012

Molluscicide

Tds Major

Metaldehyde

Slug pelleter

26/10/2012

Molluscicide

Osarex W

Metaldehyde

Slug pelleter

02/11/2012

Molluscicide

Tds Major

Metaldehyde

Slug pelleter

06/11/2012

Herbicide

Dictate

480g/litre bentazone as sodium salt in the form of soluble concentrate

Spray

Herbicide

Fidox

Prosulfocarb

Spray

Herbicide

Liberator

Flufenacet, Diflufenican

Spray

Insecticide

Gandalf

Beta-cyfluthrin

Spray

10/01/2013

Molluscicide

Tds Major

Metaldehyde

Slug pelleter

06/03/2013

Fertiliser

Sulphur Gold

Amonium sulphate-nitrate

Fertiliser spreader

08/04/2013

Fertiliser

Nitram

Amonium nitrate

Fertiliser spreader

23/04/2013

Herbicide

Quintacel5c

645 g/l (57% w/w) chlormequat chloride

Spray

Herbicide

Scitec

Trinexapac-ethyl

Spray

Fertiliser

Bittersaltz

Magnesium Sulfate

Spray

Fertiliser

Nutriphite Excel

Phosphate

Spray

30/04/2013

Fertiliser

Nitram

Amonium nitrate

Fertiliser spreader

07/05/2013

Fungicide

Bassoon

Epoxiconazole

Spray

Fungicide

Kingdom

Boscalid, Epoxiconazole

Spray

Fungicide

Bravo 500

Chlorothalonil

Spray

Herbicide

Quintacel5c

645 g/l (57% w/w) chlormequat chloride

Spray

Herbicide

Oxytril Cm

Ioxynil, Bromoxynil

Spray

27/05/2013

Fungicide

Adexar

Epoxiconazole, Fluxapyroxad

Spray

Fungicide

Bassoon

Epoxiconazole

Spray

Fungicide

Bravo 500

Chlorothalonil

Spray

19/06/2013

Fungicide

Cello

Prothioconazole, Spiroxamine, Tebuconazole

Spray

Note: These data were compiled from information provided by the farmer, by my wonderful postdoc Dr Cristina Botias-Talamantes. Keep an eye on this blog for more revelations from her ongoing work.

Dave Goulson's research lab website

Launch of the Worldwide Integrated Assessment (WIA) on the environmental impacts of systemic pesticides

Jun

27

On Tuesday this week I was in Brussels, for a press conference to launch a major series of scientific publications on the impacts of neonicotinoid insecticides on the environment. On the same day, press conferences were also held in Manila, Tokyo and Ottawa. The publications are the culmination of 5 years work involving more than 50 scientists from 4 continents, and together we reviewed evidence from >800 scientific papers. Our findings are being published as 7 papers in a special issue of the journal Environmental Science and Pollution Research. All have been accepted for publication following full, independent, scientific peer-review. The first of the seven is online now at http://link.springer.com/article/10.1007/s11356-014-3180-5; this deals with impacts on vertebrates. The rest of the papers will appear soon as the journal finishes processing them for publication.

The conclusions of our work, in brief, are that these systemic pesticides are accumulating in soils and polluting waterways and natural vegetation across the world, leading to widespread impacts on wildlife inhabiting farmland and aquatic habitats. There is also growing evidence that much of their use is unnecessary and ineffective. But you can read all about this over the coming months as the papers come out: all of them are to be open access.

On Monday, the day before the press conference and before anyone could have seen the full set of documents, I received a rebuttal of our work from Croplife, an organisation that represents the agrochemical industry. It was quite clear that they hadn’t read any of it. Their criticisms were: that the work was selective in what it reviewed (we looked at 800 papers, everything that we could find); that we looked only at lab studies (a bizarre claim, and completely untrue); that we ignored the economic importance of neonicotinoids and didn’t consider how farmers would cope without them (there is a whole paper in the WIA just on this topic).

We have also been criticised because not all of our papers are yet available. Had this been a single report, just placed on the internet without scientific review, we could easily have made it all available. This is what industry usually does. But the scientific review and editing process is slow and not all of the papers were quite ready. On the plus side, they have the huge advantage that they have all passed independent scrutiny.  

On Wednesday, Syngenta launched a request to the UK government for an exemption to the European moratorium. They want to treat 186,000 hectares of oilseed rape woth a neonicotinoid – 30% of the UK crop – because they say that otherwise there is a “danger to production”. There appears to be no scientific evidence to back up this claim. Indeed, just a week ago on 18 June an industry spokesman appeared before the UK’s Environmental Audit Committee and was asked to provide a single scientific study showing that neonicotinoid seed dressings increased yield of any arable crop. Embarrassingly, he could not. They’ve been selling neonics for 20 years, but can provide no evidence that they work!? How do they differ from the quack doctors of days gone by, who peddled cure-alls on street corners with their slick patter?

One can read Syngenta’s request another way – they seem to be conceding that 70% of the UK’s oilseed rape doesn’t need treating with neonics. Why then was 100% treated before the moratorium?

This simply appears to be a ploy by industry to bypass the EU moratorium, which was based on sound scientific evidence, and recommended by the European Food Standards Agency. If you’d like to sign a petition against their request, go to: https://secure.38degrees.org.uk/a-ban-is-a-ban

Neonics, crop losses, and ‘green activists’ – a plea for a little more accuracy in the media

Dec

20

I warn you now: this blog won’t be of much interest unless you’ve been following the neonic debate closely. It is in response to an opinion piece in the Telegraph by Christopher Booker (6 December 2014) and several recent blogs in a similar vein.

The gist of the article by Booker is that a group of dodgy scientists and green activists working for the International Union for the Conservation of Nature (IUCN) got together in 2010 and plotted to get neonics banned. They are said to have received £350,000 of EU money via the IUCN to fund this work, which ultimately resulted in the current moratorium on neonics. This moratorium has, according to Booker, “done huge damage to agriculture all over Europe”. He cites a recent EU report as saying that the cost to UK farmers alone already stands at £640 million. Booker goes on to say that there is no good evidence that neonics harm bees. He states that Defra’s own field trials had shown no damage to bees, whereas the IUCN group relied only on highly artificial laboratory experiments to reach their conclusions. He finishes with the bold claim that Owen Paterson, who fought against the moratorium and cited the Defra field trial in support of his position, was “easily the best-informed and most effective Defra secretary of state we’ve ever had”.

This all sounds like a great tale of dodgy doings, but let’s look at the actual facts for a minute. There is a group of scientists, linked to IUCN, who published a series of peer-reviewed scientific review papers on the impacts of neonics on the environment in summer 2014. These papers are all available for anyone to read at http://link.springer.com/article/10.1007/s11356-014-3470-y. They are simply a review of the existing evidence – if you are really interested, read them yourself, and you can decide whether they are any good. I was asked to join this group in summer 2012, with a view to helping to write these papers, and it seemed like a good idea – the group contains many well-respected scientists from all over the world, bringing together diverse expertise. Scientists commonly come together in this way to write lengthy reviews of important topics. It is wildly inaccurate to say, as Booker does, that we relied “only on highly artificial laboratory experiments” – our reviews examined and describe hundreds of studies, many of them conducted in the field. The Defra field trial to which Booker attaches such weight was a total cock-up since all the ‘control’ bees became exposed to pesticides, so it was never published.      

You might wonder whether I received a share of the £350,000 for my contribution. So far as I know, there never was £350,000. I received nothing – in fact on the one occasion when I attended a meeting of this group I had to pay my own travel expenses. The whole thing was done on a shoestring, as meetings of scientists usually are. I did get a free cup of coffee. 

So what about the central claim that this group somehow engineered the neonic ban? The ban was proposed in January 2013, as a direct result of the European Food Standards Agency publishing three reports on neonics which concluded that they posed an “unacceptable risk” to bees. This was voted through in April 2013, and began in December 2013. Our reviews were not published until the summer of 2014, 16 months AFTER the ban was agreed in the European Parliament. So unless members of the European Parliament are able to see into the future, it is hard to see how their decision could have been influenced in any way by a group that had not at the time published anything whatsoever.

Finally, what about the “huge damage” that the neonic ban has done, and this figure of £640 million in crop losses in the UK alone?  I follow this topic closely, but have not heard of any such report. £640 million would represent the loss of about 12% of Britain’s entire agricultural output (including arable, dairy, horticulture etc.). Since the moratorium really only applies to oilseed rape, this would require the entire crop to have been wiped out (the total annual value of this crop varies between about £400 million and £700 million). However, the first sowing of oilseed rape without neonics in the UK was august 2014. About 1.5% was lost to flea beetle, according to the Home Grown Cereal Authority. Yes, that is correct - so 98.5% of the crop is fine. The crop won’t be harvest until summer 2015, so we have no way of knowing what the yield will be, or what losses, if there are any, might be due to the absence of neonics. So where on earth does this figure come from? Perhaps Booker also possesses the gift of foresight, and has foreseen a biblical plague of locusts in the spring?

Given all these wild inaccuracies, the claim that climate-sceptic Owen Patterson was “easily the best-informed and most effective Defra secretary of state we’ve ever had” starts to seem quite reasonable by comparison. Why do newspapers publish such twaddle?

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PS To learn more about the neonicotinoid story, try reading chapter 13 of my new book, “A Buzz in the Meadow”


Crop yields higher than ever without neonics

Feb

16

In the run up to the vote on a EU-wide moratorium on use of neonicotinoids on flowering crops, which came about because of a growing body of scientific evidence that they were doing significant harm to bees, the agrochemical industry produced glossy documents declaring that this moratorium would cause massive reductions in crop yields, huge job losses in the agriculture sector, etc. etc.. You can read one such report here: http://www.hffa.info/files/wp_1_13_1.pdf This tells us that, if the moratorium were to go ahead, “the EU could lose 17 billion EUR and more; 50 thousand jobs could get lost economy-wide; and more than a million people.. would certainly suffer..”. They wanted us to believe that farmers couldn’t grow crops without these chemicals.

As you probably know, the moratorium went ahead, though the UK voted against it, presumably won over by such arguments. Now we are in the second year of the moratorium, we can start to evaluate whether this was true. Annual spring-sown crops that were sown in 2014 without neonics (sunflower and maize) have now been harvested. And the yields? Across the EU, which includes regions with a broad range of climates, yields were HIGHER that the five year average, in some regions more than 25% higher. You can see this for yourself at: http://mars.jrc.ec.europa.eu/mars/Bulletins-Publications - have a look at the December 2014 Bulletin [1].  Whatever happened to the crop devastation predicted by industry? It now starts to look like a lot of hot air and bull***t.

Right now, there is a pitched battle in Ontario – the state government is proposing major restrictions on neonics, and the agrochemical industry are pulling out all the stops to prevent it, perhaps because they fear that other parts of North America might follow suit if Ontario go ahead. They published a full page “Open letter to Ontarians” in several major newspapers, in which they claim that neonics don’t harm bees, and that they are “vital” to farmers.  Déjà vu? Ontarians might do well to look at Europe when weighing up the truth of these claims. I for one am not inclined to believe them.  

All this also makes me wonder - what other chemicals has industry been telling farmers they need, when actually they don't? How much of pesticide use is based on evidence, and how much on marketing hype/ sales pressure?


[1] Note that oilseed rape is autumn sown so the first crop without neonics wasn’t sown until August 2014, we won’t see the yields until summer 2015]

Dave Goulson's research lab website

On neonicotinoids and impartiality in scientific research.

Jan

16

Last week my group posted online a lengthy review of new evidence (post 2013) relating to the possible risks posed by neonicotinoid insecticides to the environment: 

“The Environmental Risks of Neonicotinoid Pesticides: a Review of the Evidence Post-2013”

By Thomas James Wood, Dave Goulson

doi: https://doi.org/10.1101/098897

Free to view here: http://biorxiv.org/content/early/2017/01/06/098897

Funded by Greenpeace.

The rationale for compiling this review was that, in 2013, the European Food Standards Agency (EFSA) published a series of reports on three neonicotinoids (imidacloprid, thiamethoxam and clothianidin) which concluded that these chemicals pose an “unacceptable risk to bees”.  This conclusion led to the current EU moratorium which prevents the use of these three chemicals on flowering crops that bees might visit. EFSA are currently re-evaluating the position in the light of new scientific studies, and are expected to report back soon to the EU with a recommendation as to whether the moratorium should be rescinded, extended indefinitely in its current form or broadened to cover other uses (e.g. on non-flowering crops). It has been suggested that EFSA are compromised by close links with the agrochemical industry (though I have seen no evidence of this). Certainly industry are lobbying strongly to overturn the moratorium.  

Greenpeace asked us to write our own, independent review of the new evidence. Our review will make an interesting comparison with that produced by EFSA (now expected September 2017). Greenpeace paid the salary of my just-finishing PhD student, Tom Wood, for 4 months to complete this work with my help. For the record, other than Tom’s salary, they have not given any money to me or my lab, either recently or in the past. However, this does raise interesting issues about impartiality. I have previously pointed out that studies funded by, or carried out by, the agrochemical industry almost never find that neonicotinoids harm bees, while independent studies very often do find strong evidence of harm. This worries me because science depends completely on the honesty and impartiality of the experimenter. It is all too easy to bias results, consciously or subconsciously, in either direction. When patterns like this emerge, what is the lay-person to make of it? Sadly, it undermines public trust in science, at a time when good scientific evidence, and trust in this evidence, is urgently needed if we are to find a way through the myriad of terrifying environmental problems we are creating (climate change being an obvious example).     

So when we were offered money by a campaign group to write this review, we had to think very carefully. Greenpeace gave us written assurances that they would not attempt to influence what we wrote in any way, and they did not. Nonetheless, I am sure that some will say that this is just as flawed as industry evaluating the safety of their own chemicals. Of course there is one fundamental difference. When an agrochemical company conducts research on the safety of its own chemicals, it has a huge incentive to find a negative result. Pesticide sales are worth (literally) many billions of dollars per year. On the other hand, Tom and I get no direct benefit from publishing articles about pesticides, whatever we say. We might be more likely to get funding from Greenpeace in the future if they like what we write, so perhaps we are compromised to some extent too. On the other hand, if we published research that concluded that neonicotinoids were harmless we might be more likely to get funding from industry (though I think I may have burned that bridge long ago!), and industry has an awful lot more money than Greenpeace. So it is not clear that we have an obvious incentive to be biased, consciously or subconsciously, in one way or the other.

Nevertheless, I worry about impartiality and objectivity every day. I ask myself whether I am analysing patterns in the data correctly, or am I looking to confirm my own subconscious biases? When we conduct experiments in my lab, we try to report both negative and positive results as best we can (though journal editors don’t much like negative results). We recently published a paper which showed that low doses of the neonicotinoid clothianidin did not seem to have a measureable effect on learning or egg-laying in worker bumblebees (https://peerj.com/articles/1808.pdf ). If I had some sort of strange personal agenda to get neonicotinoids banned why would I publish this? With over 260 scientific publications to my name, I am not in desperate need of one more, and it might have been convenient to let this one slide, but we did not. We even paid the journal fees to get it published.   

Having spent six years studying neonicotinoids, I am pretty convinced that they are contributing to wildlife declines, not just those of bees. Hundreds of scientific studies from a huge diversity of different scientists on different continents conclude that they are harming bees, butterflies, aquatic insects, even birds and perhaps now bats (while a few studies found no effects). The balance of evidence seems to me to be overwhelmingly in one direction, despite industry efforts to obfuscate. That is my opinion, and it is not for sale. Unavoidably, all scientists in any field have opinions. Does this make us bad scientists? I hope not.

Of course, in an ideal world all research of this type would be funded entirely independently of stakeholders on either side. We don’t live in that world. So, if you have time, read the review. Make up your own mind whether it is fair or not.

The review contains no new data; it is simply a summary of what has been published in the scientific literature in the last four years. We have taken the unusual step of posting it on Biorxiv so that others can comment. This review has not yet been formally published; it is a work in progress. We encourage any interested party to give their opinion: have we missed critical information, have we wrongly interpreted studies? Once we have received comments, we hope to submit a final version for formal publication. This is not a procedure I have ever followed before, but seems to be a growing trend in this age of rapid, digital, open-access publishing.

So, comments please….