The EU guideline that allows to kill most insects

The EFSA is using outdated and very industry friendly guidelines to assess the effect of pesticides on insects. We have urged the European Commission to revise a very important guideline. It is one of those hidden documents that allow immense damage to biodiversity. Written by a Novartis (now Syngenta) employee, it has been in use for over 20 years. With devastating effects.

The Guideline on Terrestrial Ecotoxicology does not sound very alarming. But what is it about? The 'non-target arthropods' section of the guideline tells industry what tests they must perform to show the effect of pesticides on non-target insects and other arthropods. If the results are within the limits set by the guideline it’s a go. This creates the false impression that pesticides are harmless to bugs.

Insects are extremely important in agriculture. As pollinators, they ensure the production of most fruits, and the reproduction of most fruits and vegetables. A collapse of pollinators seriously endangers food production. As natural predators of pests, they are also responsible for pest control. Plus they play an important role in soil life in interaction with other species. The soil food web breaks down organic matter into nutrients for plants. It also forms humus and stores carbon into the soil. It helps to make the soil spongy and able to absorb rain. All this is extremely important for healthy plants, water retention and sustainable food security. This fundamental work is done by an incredibly diverse mix of fungi, bacteria, archaea, algae, worms and arthropods like small insects and mites.

Pesticides can have a disastrous effect on beneficial insects, destroying natural pest control in a single spraying. In turn, farmers will need to use more insecticides to control pests as natural control was destroyed. In addition, pests become resistant to pesticides, which is not the case with natural pest control. Farmers need to use more quantities and more toxic pesticides or cocktails of pesticides to overcome the inevitable resistance. This is called the pesticide treadmill: a vicious circle where the destruction of biodiversity is at the heart of chemical agriculture.

Pesticides can also seriously harm soil life. They can kill or damage essential parts of the chain. They can change or disturb the delicate equilibrium. To pacify concerns, the regulators have included a soil life test in the authorisation process. That posed a serious threat for the pesticide producers. Most pesticides are made to kill and usually do not see the difference between the very few ‘target’ and the very many ‘non-target’ weeds, fungi or insects.

A serious test protocol could protect biodiversity and soil life. However, it probably would also limit the use of pesticides. So the representatives of the Pesticide industry in the EU regulatory panels made sure that their products would not be affected.


What is in the Guidance document for terrestrial ecotoxicology?

The guidance document gives pesticide producers the choice to use one of four different species: Orius laevigatus (a predatory bug), Chrysoperla carnea (green lacewing), Coccinella septempunctata (sevenspotted ladybird) and Aleochara bilineata (a rove beetle). These are not necessarily the ones common in the environment where the pesticide is applied.

The guideline favours the insect species that are easy to grow in a laboratory, not the more complicated ones. And the industry can choose which one they present. The effect of pesticides can be quite different on different species. So if you try three different species of test insects, you can present the study with the least effect and not use the others. “That’s why they test and if it is negative, they are allowed to test more species, and use the least sensitive and most convenient methodology,” says Hans Muilerman from PAN Europe.


Misleading concept of ‘recovery’

In aquatic and terrestrial (arthropods) risk assessment a very convenient concept was introduced.  This concept of ‘recovery’ is the ‘assumption’ that if organisms are harmed or killed by pesticides, their fellow organisms will replace them and enable them to reconstitute the original population. This approach makes killing non-target organisms sound much less problematic and acceptable. Killing 50% of the organisms, like beetles, butterflies, bees with one (yes, only one!) pesticide application is the acceptable benchmark. Even higher mortality percentages could still result in the same verdict: acceptable. 

The EU guideline on terrestrial risk assessment from 2002 is not very clear what the base is for the use of ‘recovery’ in the higher tiers. It just refers to ESCORT 2 (European Standard Characteristics of Non-Target Arthropod Regulatory Testing). (1)

The ESCORT-proceedings were a result of EPPO/SETAC-organised meetings, not coordinated by the EU. In ESCORT it is suggested that in-crop recovery for arthropods should take place within one year. For the off-crop situation, it is only stated that the duration of the effect and the range of taxa affected should be taken into consideration. This is reported by Candolfi et al. (2). This should not necessarily result in the denial of authorisation of the pesticide active substance, but result in risk management options instead. These risk management options are specified in Candolfi et al (2). 

And who is this very helpful mister Candolfi, one might wonder? He worked at the time for Novartis Crop protection, now Syngenta. The picture becomes even more worrying when you take a closer look into who else helped drafting the ‘guideline’ as a result of these meetings: Neumann (Novartis, now Syngenta), Heimbach (Bayer), Campbell (Zeneca, now Syngenta), Romijn (Rhone-Poulenc) are a few. Only three public servants were part of the Group: Oomen (The Netherlands) and 2 non-experts from OECD secretariat. Industry thus had a boulevard to impose their approach!

Killing effect

So in the EU, pesticides are tested for their effect on non-target insects and other small life forms.

Fifty percent dead with 1 application is considered as acceptable.  There is even an exception for 100% of life to be killed. 'Don't worry, it will come back', is the argument. As if insects and other useful living organisms were exposed to pesticide spraying just once a year. For over 20 years since the introduction of the guideline pesticides have been allowed to eradicate life: pesticides are sometimes sprayed more than 20 times a year on the same crop. This is one of the important reasons we’re now in a biodiversity crisis. Populations of wild bees, butterflies, beetles and insect eating birds have collapsed.

So it is high time for a new guideline. That shouldn’t be so hard. Why does it take so long? Well, some people might not be so happy with an effective guideline that protects biodiversity. Where is this process now? In 2016, EFSA started reviewing the issue of ‘recovery’ in ecological risk assessment. First an external scientific report (4) was commissioned by EFSA, summarising academic literature. From this report it appears that ‘recovery’ can only be expected in specific cases. If the environment is already under stress, like in agricultural areas, external recovery (outside the fields) cannot be expected to occur. On the contrary, ecological stress may increase due to synergistic effects of different pesticides used, which should be taken into account. Does it require a PhD to understand that we have a problem here?

For the rest, nothing happened. So anno 2024 EFSA and national institutions still work with industry guidelines that basically allow the killing of all insects. More or less the same is the case with amphibians (no guidance document yet) or aquatic species (guidance document from 2015). And instead of compensating this dramatic situation by taking into account academic research on the toxicity of pesticides on insects, EU regulators keep rejecting it and giving importance only to industry tests that lead…to an accepted 100% mortality!

So much for biodiversity ……



(1) ESCORT2 is not a public document. However, it is used for Risk Assessment so there is no reason it should not to be public. So we publish it here on our website.

 (2) Principles for regulatory testing and interpretation of semi-field and field studies with non-target arthropods Gandolfi et al, 2000)

(3) Scientific Committee, 2016. Scientific opinion on recovery in environmental risk assessments at EFSA. EFSA Journal 2016; 14(2):4313.

(4) M. Kattwinkel, J. Römbke, M. Liess; Ecological recovery of populations of vulnerable species driving the risk assessment of pesticides. Supporting Publications 2012:EN-338. [98 pp.]. Available online:

(5) PAN Europe letter to EFSA

(6) PAN Europe letter to SCoPAFF 231206


From PAN Europe’s letter to SCoPAFF on December 6, 2023 on the Guidance document on Terrestrial Ecotoxicology

“While we welcome the announcement that the revision of the overdue guidance document on terrestrial ecotoxicology now stands as a priority, we are still waiting to see concrete progress to increase the level of protection for biodiversity and ecosystems. In light of the poor state of insects and biodiversity in agricultural areas and their surroundings, it is unacceptable that its 2002 version is still in use. The current guidance sets a threshold for insects of 2 x LD50 in the field, potentially causing 100% mortality, while assuming the possibility of ‘recovery’ within the same season. However, in reality, insect populations are dramatically declining. This guidance document was prepared and adopted under totally unacceptable conditions as regards to transparency, independence and participation and is as a result far from being in line with the current science. Its design took place during the EPPO/SETAC meetings (‘named ‘ESCORT) which were chaired by a Novartis-employee and included a range of other industry-employees from Novartis, Bayer, Zeneca and Rhone-Poulenc), while other stakeholders were not invited. This ensures a ‘desired outcome’, i.e. a guidance document that does not restrict the approval of pesticides highly toxic for terrestrial organisms.”

© Pesticide Action Network Europe (PAN Europe), Rue de la Pacification 67, 1000, Brussels, Belgium, Tel. +32 2 318 62 55

Pesticide Action Network Europe (PAN Europe) gratefully acknowledges the financial support from the European Union, European Commission, DG Environment, LIFE programme. Sole responsibility for this publication lies with the authors and the funders are not responsible for any use that may be made of the information contained herein.