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studies, and are expected to report back soon to the EU with a recommendation as to whether the moratorium should be rescinded, extended indefinitely in its current form or broadened to cover other uses (e.g. on non-flowering crops).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.