Misleading calculation: EU plans for pesticide reduction at risk

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Pesticide use in agriculture must be reduced to protect biodiversity.
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The use of pesticides is to be halved by 2030, according to the draft EU regulation on pesticide reduction. This goal is to be verified using pesticide sales data. In the view of the German Environment Agency this method is misleading. Pesticides that are no longer approved are weighted too high. Decreasing sales figures would indicate a decreasing trend, which does not happen in the field.

The SUR: A turning point towards sustainable agriculture?

On 24 October 2023, the EU Parliament's Environment Committee voted on a new regulation to halve pesticide use by 2030 (Sustainable Use Regulation - SUR). UBA President Dirk Messner said: “Next to the climate crisis, the preservation of biodiversity is the greatest challenge facing humanity. The success of the SUR will determine whether something is done to counteract the extinction of species in agricultural areas. However, the position now agreed upon in committee still has decisive weaknesses, first and foremost the method by which progress is to be measured. This should be improved.”

Pesticide reduction on paper does not protect the environment  

In order to check whether the use of pesticides will really be halved by 2030, the SUR currently provides the Harmonised Risk Indicator (HRI1 according to Annex 1). This indicator is supported by the European Commission and now also by the Environment Committee of the European Parliament. From UBA's point of view, this method is unsuitable: it calculates a decrease in pesticide use where none actually exists. This would undermine the purpose of the planned regulation. Consequence: The extinction of species in agricultural areas would continue unabated despite good figures on paper. This criticism of the indicator has already been voiced several times by the European Court of Auditors and UBA.

The planned measurement method must be corrected

The fact that the indicator is based solely on sales volumes makes little sense. The more effective and thus also more toxic a pesticide is, the lower its use and sales quantities and thus its calculated contribution to the overall risk. As a result, highly effective and toxic insecticides are hardly included in the calculation. Herbicides or active substances of natural origin, on the other hand, which have to be used in much larger quantities to be effective, dominate the trend. Substances such as sulphur would thus top the ranking of the most dangerous pesticides, rather than highly toxic insecticides such as pyrethroids.

Instead of considering the effectiveness and thus the toxicity of pesticides, the sales volumes are multiplied by non-comprehensible weighting factors. Especially relevant is the impact of a very high weighting of non-approved active substances (see graph): For active substances that lose their approval, sales figures decline sharply. These declining sales figures are now retroactively weighted much higher. For the years before the end of the approval - in which the substance is still sold a lot - this results in a disproportionately high calculated risk. From the day the authorisation expires and the sales figures drop, the calculated risk decreases abruptly. This decrease is seen as an enormous success of pesticide reduction, but is solely due to the excessively high weighting factor.

The goal of the SUR would thus be achieved on paper shortly after its adoption, without any real reduction in pesticide use taking place.

The method can be easily corrected: Sales volumes of active substances should not be weighted more heavily based on their expiring approval. In addition, the sales figures of active substances would have to be standardised on the basis of their specific effectiveness. More information on this can be found here.

Whether the new EU regulation is a win for the environment and health will therefore be decided more by the choice of measurement method than by the reduction targets set.

Grafische Darstellung der EU Absatzzahlen
How the EU calculates the pesticide risk down to a minimum.

Left: Pure sales figures of pesticides in the EU from 2011 to 2021. Right: Decrease in pesticide risk calculated from this according to the HRI1 methodology. Accordingly, pesticides are divided into four groups and their sales figures are multiplied by the following weighting factors: Group 1 ─ Low-risk active substances: factor 1, Group 2 ─ Approved active substances (standard): factor 8, Group 3 ─ Candidates for Substitution (CfS): factor 16, Group 4 ─ Non-approved active substances: factor 64. The sales figures of all pesticides weighted in this way are subsequently added together. The grouping corresponds to the current approval status of the pesticides in 2021. Both sales figures (left) and HRI1 risk (right) are given as percentages relative to the baseline period 2011-2013. The percentage of Group 1 is < 0.01% and therefore not evident graphically.
The visualization of the four groups shows the systematic error of the HRI1 methodology. In fact, only the sales figures for non-approved active substances of group 4 are declining. This decrease in sales figures is drastically weighted by the indicator and dominates the HRI1 trend as a decrease in risk. This strong weighting is not scientifically justified and therefore misleading. The goal of the SUR would be achieved on paper within a foreseeable time after its adoption, without any reduction in pesticide use taking place in reality.

Source: German Environment Agency Download figures
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