by Louise Payton, Soil Association
Surely, this is the final, fatal blow for neonicotinoids.
There must have been a point when the tobacco industry realised they weren’t fooling anyone anymore – when the evidence on the link between lung cancer and smoking became all too clear. It looks like the same moment has come for the pesticide industry and their insecticides, neonicotinoids.
Neonicotinoids are a group of insecticides worth 3.9 billion dollars. For years evidence has been mounting that they harm wildlife, with researchers mainly focusing on the harm to bees. Bayer and Syngenta have, unsurprisingly, consistently denied the science.
Today, with the publication of the results from a major field trial by the Centre of Ecology and Hydrology (CEH), and another study from Canada, scientists like bee expert Dave Goulson, are saying that to further deny the need for a ban on these pesticides is “no longer a tenable position”. Even when plans for the major field trial were announced it was hailed as THE study to end the debate on neonicotinoids. As Fiona Fox, director of the Science Media Centre in London said: “If the CEH trial does show adverse effects from their products in the field, science-based companies will have to accept them.”
Of course, given the damming nature of the results, they haven’t accepted them.
As Bayer said
“We do not share the Centre for Ecology and Hydrology's interpretation that adverse effects of the seed treatments can be concluded from this study, and we remain confident that neonicotinoids are safe when used and applied responsibly."
This response looks ludicrous when compared to the statements of the study’s authors, and so many experts today in the press (apart from a small few who mysteriously continue to argue that there still isn’t enough evidence to warrant a ban). Bayer and Syngenta part-funded the study and got to have a role in scrutinising the method, so their only course of action this time is to just try to weakly deny the results, rather than criticise the methodology – their usual line of defence.
The National Farmers Union have also long denied the evidence. Amazingly, they have continued to do so, stating that the evidence is still not strong enough and that neonicotinoids are crucial for farmers; “while this CEH study provides more useful information, we still don’t have that definitive evidence for the impact of neonicotinoids.” (Guy Smith, from the National Farmers Union).
I won’t go into the criticisms of the evidence – the voice of experts out there on the strength of the results speak louder than my own expertise could. But it is worth having a quick look at the impact on farmers. A huge amount of money (£2.8 million for this field trial alone) has been spent on looking at the cost of these neonicotinoids. However, few, if any independent peer-reviewed studies have looked at whether neonicotinoids actually help farmers by raising yields. Matt Shardlow, from Buglife, said: "Let’s be VERY clear – there are no reputable or well referenced estimates of the cost to farmers."
We can compare the yields of oil seed rape crops in the UK before and after the partial ban though – figure 1. Based on the comparatively low yields in 2016, it has been argued that the ban has had a terrible effect. But actually, taken across a 15 year period, yields have fluctuated between around 3 and 4 tonnes, regardless of whether neonicotinoids were under a ban or not. However, given that these insecticides can harm pollinators of crops and kill predatory insects that control pests like slugs (unaffected by neonics) – two peer-reviewed studies suggest that neonics can actually reduce yields.
This graph of government data shows variation in yields for arable crops over time, including oil seed rape (OSR) at the bottom. The yields for OSR after the ban, as reported in Mark Avery’s blog, have been plotted in green (mixed year for neonicotinoid use as the ban came in) and red (after the ban).
Time for a total ban
A worrying finding from both the studies published today, is that neonicotinoids were found to have widely polluted the farms studied. Most neonicotinoids that harmed the bees had actually come from contaminated wildflowers and included a type of neonic not used for in the treatment sites. The current ban only applies to flowering crops like oil seed rape. Yet 3,574 and 830,518 hectares of cereals were treated with imidcloprid and clothianidin in 2014, suggesting vasts amount of these chemicals are still polluting our farmland. A total ban is urgently needed – but sadly the legacy of neonicotinoids will continue for several years after. It makes me desperately sad to think, as I walk past farmland hedgerows lined with flowers, that they may be saturated in these chemicals and for years to come.
We need a hard look at pesticide regulation
What all this evidence clearly shows however, is that neonicotinoids should never have been cleared for use. As one of the researchers of the CEH study said ““Our findings also raise important questions about the basis for regulatory testing of future pesticides.”
Not only did current regulations fail to realise the impact on bees (and other wildlife, not yet studied as intensively as bees) – it also continues to fail to ignore the mixing effect of pesticides. This is the so called ‘cocktail effect’ where pesticides, not necessarily toxic, combine to have harmful effects. The Canadian study, also published today showed that a commonly used fungicide, thought to be non-toxic, combines with neonicotinoids to double their toxicity. Dozens of different chemicals have been shown to be contaminating wildflower pollen, soils and water ways. As Dave Goulson said:
In my view we should also consider the bigger picture; the current model of farming based on huge monocultures treated with dozens of pesticides is causing devastating environmental harm, undermining vital ecosystem services that keep us all alive. Simply banning neonics and replacing them with some other toxin will not solve the problem.
Learn from organic
A good first step would be to learn from organic farms, which support a whopping 50% more pollinator species than non-organic farms, as well as 75% more plant species, more flowers, birds and healthier soil that isn’t contaminated with cocktails of chemicals.