EASAC-report Neonicotinoids and their substitutes in sustainable pest control

Since restrictions on three neonicotinoids were introduced in 2018 in the European Union (EU), other insecticides with similar modes of action have entered the EU market, raising concerns that they may pose similar risks to honeybees and other non-target species. Meanwhile, agrochemical innovation continues to develop new molecules that exploit the same or similar neuroactive mechanisms to the original neonicotinoids. At the same time, debate is underway on the sustainable use of pesticides, on how to evaluate the environmental risk of existing and new pesticides, and on adapting regulations with the European Green Deal, Farm to Fork, and Biodiversity strategies.

As part of the Farm to Fork Strategy to reduce environmental impact of agricultural land, the European Commission has proposed a new Regulation on the Sustainable Use of Plant Protection Products (PPPs) that will seek to better apply integrated pest management 
(IPM) and reduce pesticide use and risk. In this report, the European Academies’ Science Advisory Council (EASAC) reviews recent research into the effects of neonicotinoids and assesses its implications for the current policy debate. The policy proposals are especially important because current climate trends may lead to greater pesticide use with associated health and environmental damage risks, increased pesticide resistance and accumulation of persistent pesticides.

The report summarises the results of research in recent years and strengthens earlier conclusions in EASAC’s 2015 review on the wider ecosystem effects of neonicotinoids. This supports the continuation of existing restrictions and of measures to minimise future use—especially to mitigate the threat to future food security from the continued decline in insects (including pollinators). 

EASAC notes that although outdoor use has been restricted, many Member States have used provisions for emergency authorisations to continue neonicotinoid use—especially for controlling flea beetle in oilseed rape and in sugar beet to avoid yellow leaf virus. The European Court recently ruled that such trends do not meet the Commission’s guidance that emergency authorisations should be a last resort.

The restrictions on the original neonicotinoids created incentives to develop neonicotinoid substitutes that exploit the same insect neural mechanisms. Two such products, a sulfoximine (sulfoxaflor) and a butanolide (flupyradifurone), have been approved as active substances in plant protection products, but many more chemical molecules are under development. With similar mechanisms, there is a risk that they will become ‘regrettable substitutions’ whose impacts turn out to be similar to, or worse than, the neonicotinoids they are designed to replace. Caution is thus needed in evaluating new molecules that inhibit nicotinic acetylcholine receptors and it should be assumed that similar broad ecosystem effects may occur unless applicants demonstrate otherwise when applying for regulatory approval.

Work continues to improve the regulatory process. This report describes some of the underlying issues in environmental risk assessment (ERA) methods and how to take into account accumulation of pesticides that may be used more than once in a season, exposure to other pesticides and to chemicals present in formulated products (co-formulants), stress factors such as viruses or parasites, uncertainties in applying the results to real field ecological conditions, or abiotic factors (e.g. soil pH or organic content) that can affect the toxicity of the pesticide.

To address these challenges, we support measures under way by the European Food Safety Authority 
(EFSA) towards a ‘Systems-based ERA’ approach. A systems approach requires more data on post-approval use and effects, and EASAC agrees with other observers that the current extent of monitoring concentrations of, and exposures to, approved PPPs is insufficient 
to estimate their effects on human health and the environment, and for early identification of emerging problems. The Commission should continue to advocate improvements in data availability because this will offer greater protection against environmental damage in Member States’ agriculture.

‘Low-risk’ pesticides can be based on bacteria, fungi and viruses, as well as substances such as blood, limestone or pepper. In principle, low-risk products should be preferred by farmers in managing pests, and should have a higher priority than more toxic synthetic chemicals in the IPM hierarchy. We note proposals to simplify the approval processes for such products but caution that context remains important, and limiting the designation of low risk just to those pesticides’ toxicological profile could be misleading from an environmental perspective.

Even with an improved regulatory testing regime, future regrettable substitutions may never be avoidable. Moreover, concerns about leakage of pesticide residues into organic agriculture that the Farm to Fork Strategy seeks to expand, and over the overshooting of planetary boundaries for novel (chemical) entities, add to the urgency of substantially reducing use of synthetic pesticides overall.

Concerning the priority given to IPM, this report points out that, despite much historical success, IPM has not prevented a continued growth in the use of pesticides worldwide. The report explores reasons why IPM has not achieved its full potential and concludes that an effective IPM strategy needs support, incentives and regulatory pressures. The following are discussed:

• Ensuring that there is a common understanding of what IPM is, and of the IPM pyramid where chemical control is the option of last resort. A clear definition is required and options are given in the report.
• Education and awareness. IPM increases the complexity of farming management and requires additional decision-making, and detailed husbandry knowledge and experience, increasing the need for external advice and support.
• Help for farmers to make new investments.
• Providing basic monitoring services.
• Incentive-based policies where EASAC commends the Commission’s current actions to support deployment by farmers and encourage further integration of IPM practices and technologies through the incentives in the Common Agricultural Policy (CAP).
• Recognising the potential for carbon offsetting in support mechanisms under the CAP.
• Agrochemical industry can support the transition to IPM by moving away from mass-market sales
  of treated seeds and crop protection options, to more target-specific and niche markets that support farmers’ moves to increase crop biodiversity and apply biological and other control mechanisms.
• It is important to take a landscape perspective that extends beyond the single farm; pest populations migrate across farms and wider areas, so coordinated pest control actions are the optimal approach.

This report asks whether there is a role for neonicotinoids in IPM. We confirm that prophylactic or blanket uses such as seed pre-treatment are incompatible with IPM. Where, having applied the non-chemical actions in the IPM pyramid, a final option of chemical control is considered, the question becomes whether neonicotinoids should be automatically excluded from consideration; for instance, in local targeted sprays in precision agriculture. However, the risk of accumulation in soil, their persistence, toxicity to non-target organisms and water solubility argue for continued caution.

Ultimately, IPM needs to become the mainstream approach if the objectives of the Green Deal are to be met. The challenge is that IPM may be more expensive in cost, work and manpower and also needs to meet farmers’ objectives for crop productivity and income security. Evidence that IPM is not in conflict with food security is thus critical in persuading Member States to support the Commission’s proposals, especially following the Russian invasion of Ukraine. In the latter context, in reducing the need for chemical fertilisers and PPPs, IPM could improve agriculture’s resistance to such supply shocks.

EASAC agrees with the Commission that support for IPM should be accompanied by quantitative targets for reducing the uses of pesticides. Although reduction in actual use can be quantitative, assessing risk requires integrating different aspects (from human health to biodiversity and ecosystem services), and deciding a single indicator will depend on the formula selected. The validity of the current Harmonised Risk Indicators (HRIs) in use is discussed and that the current formulae and targets may have the effect of ‘locking in’ the increases in the toxic load to agricultural landscapes that have occurred in the past 20 years. From an environmental perspective, reduction targets should be substantially increased and a better science-based indicator developed that takes into account a PPP’s persistence in the environment, its toxicity to non-target organisms (especially pollinators and natural enemies of pests) and effectiveness in controlling the target pest, as well as concerns over human toxicity.

Finally, the report examines a wide range of new technologies that support and facilitate the application of IPM and point to several programmes (EU-wide and in Member States) that support IPM development.