A careful reading of these two texts – the first concerning possible alternatives to neonicotinoids and the second on their impact on human health – is of interest, as they contradict what is usually understood about these “dangerous insecticides”. Indeed, these two reports provide a reassuring look, ANSES experts having concluded that “the data set […] does not show an unacceptable risk to human health”. To discuss human health issues to ban these chemicals, as is the case in certain ministerial corridors, is therefore pure hypocrisy …
Admittedly, a drawback has been reported for thiacloprid. However, ANSES is careful not to propose its ban, as its experts note that thiacloprid presents less risk to human health than alternatives currently available on the market for maize seed treatment uses. ANSES considers, however, that it would be desirable to “minimize the use of products based on this substance by 2018”, underlining “the significant increase in its use (…) over the 2010-2015 period”.
However, the increase in its use – 43 tonnes in 2013 against 119 tonnes in 2014 – is simply the result of the respective prohibitions of certain uses of imidacloprid and thiamethoxam. To make matters worse, ANSES recognizes that these last two chemicals are much more effective against soil pests (especially wireworms), while possessing a toxicological profile that is better for human health than the molecule that has taken over. On the other hand, thiacloprid would be less toxic for bees, which is the main reason for the strategic choice of former Agriculture Minister Stéphane Le Foll, but which, in the end, does not represent an improvement from the point of view of global environmental and health impacts. On the contrary.
The report on possible alternatives to neonicotinoids is also particularly interesting. For several uses, no alternative could be identified, especially for the production of lettuce greens. ANSES also warns against a national ban that could “result in the importation of nursery plants treated with neonicotinoids” . Same story for attacks of geomyze flies on maize, reported mainly in the west of France, but also in the Paris basin and in Rhône-Alpes. A survey carried out by Arvalis-Institut du végétal and the Brittany Chamber of Agriculture among farmers on the 2016 campaign revealed that between 80,000 and 100,000 ha of Breton maize would have been affected by geomyze. By comparing the effectiveness of the different seed treatments used in the sample, the survey demonstrated the effectiveness of thiacloprid, which “reduced on average 83% the impact of geomyzes on plots” . Once again, ANSES notes that it has not identified “any alternative”.
Moving in the wrong direction ecologically
Regarding the production of beets, a ban on neonicotinoids would also present health and ecological problems relative to possible alternatives that all pose higher risks: “Among the chemical substances, neonicotinoids have lower risk indicators for human health (food and non-food risk), ” says the report. “For mammals and earthworms, tefluthrin [one of the alternative chemical solutions] has a higher risk indicator than thiamethoxam but lower than that of imidacloprid” , notes the report which states that “no non-chemical alternative sufficiently effective and operational has been identified ” . “The only alternative identified is another phytopharmaceutical preparation with a marketing authorization for this purpose, based on lambda-cyhalothrin and pirimicarb. It has a risk indicator linked to a higher non-food exposure than neonicotinoids. “
For cereal crops, which are by far the main use of imidacloprid, the finding is similar: “Of the chemical substances authorized for this use, imidacloprid has the lowest food risk indicator on all cereals. The highest indicators are that of thiacloprid on oats and those of pyrethroids on other cereals (including deltamethrin and alpha-cypermethrin). Regarding the risk to human health excluding diet, neonicotinoids have a lower risk indicator than their alternatives and tefluthrin has the highest risk indicator. “
Increasing the risk of resistance
To be clear, the only truly credible alternatives where they exist are around the use of pyrethroids as a foliar spray to replace the use of neonicotinoids in seed treatments. Already widely used, this family of insecticides is not without problems, especially because of its uneven effectiveness. An increase in its use will necessarily increase the risk of resistance, and thus ultimately leave it even less effective. This problem had already been identified by ANSES in a report published in 2014, particularly with regard to resistance for aphids which serve as a vector for beet jaundice virus. The authors concluded that 100% of peach aphids (Myzus persicae) were already resistant to pyrethroids.
Moreover, depriving farmers of neonicotinoids will clearly have an impact on the Indicator of Frequency of Treatment (IFT) whose rapid reduction remains one of the main objectives of the Ecophyto 2 plan. Replacing a seed treatment with one to three foliar applications – as will be the case for cereals and beets – will, on the contrary, considerably increase it.
Finally, it is curious that the economic impact of the implementation of alternatives has not been addressed by ANSES, whereas in the referral signed by Stéphane Le Foll, the request to examine “the economic and the possible consequences of practical implementation for agricultural holdings ” was clearly required. A simple omission, some will plead …