Risks and benefits of plant protection products containing neonicotinoids compared with their alternatives

In its Article 125, the Act of 8 August 2016 "for the restoration of biodiversity, nature and landscapes" provides for a ban on the use of plant protection products containing active substances from the neonicotinoid class and seeds treated with these products, with effect from 1 September 2018. The Act also stipulates that waivers may be granted until 1 July 2020 on the basis of a comparison prepared by ANSES of the benefits and risks associated with the uses of these products, with those of substitute products or alternative methods. Furthermore, a European regulation adopted by the Member States on 27 April 2018, restricting the uses for three neonicotinoid active substances (Thiametoxam, Imidacloprid, Clothianidin) to use in greenhouses only, will be enacted and will also apply to French marketing authorisations for plant protection products containing these substances.

In this context, ANSES received a formal request to conduct an assessment weighing up the risks and benefits of plant protection products containing neonicotinoids, compared with their chemical and non-chemical alternatives. The Agency first developed a methodology for identifying alternatives, published in March 2017, which can be used to compare the alternative control methods (chemical and non-chemical) for each of the neonicotinoid uses on the basis of four criteria: the effectiveness, operational capability, sustainability and practicality of each method considered.

The approach adopted made it possible to identify and assess control methods likely to offer an alternative to the use of neonicotinoids (chemical or agronomic) with immediate effect. Once these alternatives were identified, risk indicators for humans and the environment, including pollinators, were established for the chemical alternatives. Lastly, a third component dealt with the impact of the ban on neonicotinoid use and the implementation of alternatives on agricultural activity.

Identification of alternatives to the authorised uses of neonicotinoids

One hundred and thirty authorised uses of neonicotinoids were studied.

For most of the uses, sufficiently effective and operational chemical and non-chemical alternatives were identified.

In six cases, no chemical or non-chemical alternatives meeting these criteria were identified. In 89% of cases, the solutions to replace neonicotinoids were based on the use of other active substances, especially pyrethrinoids. In 39% of cases, the chemical alternatives relied on the same class of active substances, a single active substance or a single marketed product. And in 78% of the analysed cases, there was at least one non-chemical alternative solution. In the current state of knowledge, the non-chemical methods appearing to be most suitable for immediately, effectively and sustainably replacing neonicotinoids are biological control, physical control by applying a protective layer (paraffin oil, clay, etc.) and mating disruption, when these methods are already available in France or easily transferable.

On a case-by-case basis, other non-chemical alternative methods such as cultivation methods can replace neonicotinoids, although their inherent effectiveness is lower.

Risk indicators for human health and the environment related to the uses of neonicotinoids compared with their chemical alternatives

For each authorised use of neonicotinoids, for the chemical active substances contained in preparations with an MA for this use, two risk indicators were calculated for human health (risks related to dietary and non-dietary exposure) as well as six for the environment (risk for birds, mammals, earthworms, aquatic organisms, bees and groundwater).

Depending on the use and the risk in question (dietary, non-dietary, bees, aquatic organisms, etc.), the comparison of risk indicators associated with neonicotinoids with those associated with their chemical alternatives could lead to different results. It was therefore not possible to draw an overall, concise conclusion as to the active substances with the least unfavourable risk profiles compared to that of neonicotinoids.

Impact of the ban on neonicotinoid use and the implementation of alternatives on agricultural activity

Carrying out an assessment of the agricultural impact of the ban on neonicotinoids, aside from the fact that it does not address the environmental, health and social consequences for which there is no scientific consensus, raises a number of challenges that were not resolved, especially concerning the methodology, and data availability and reliability.

In particular, the impact of the ban on neonicotinoids on agricultural activity is difficult to anticipate, mainly due to the wide variety of neonicotinoid uses and the fact that the extensive use of these substances to treat seeds is partly an “insurance” measure. Even so, the Agency is proposing an indicative list of criteria for assessing the impact on sector activity. This could inform decision-making and is an approach that could be taken into account after weighting according to the objective at hand.

Therefore, the prospects for alternative practices have yet to be confirmed and economic analysis methods devoted to the transformation and adaptation capacities of agricultural systems need to be developed.

ANSES’s conclusions and recommendations

It should be remembered that with regard to pest control,no single method is sufficiently effective but a combination of methods should be considered in the framework of an integrated control approach. Prophylactic uses (including seed treatments) should be replaced with the regular observation of pests in plots (epidemiological surveillance), the priority implementation of all non-chemical control methods (combination of partial-effect methods) and lastly, if necessary, the application of an insecticide (with the lowest possible toxicity and the narrowest possible efficacy spectrum) based on pest observations above the damage thresholds (those that can have economic or health impacts).

For most of the studied uses, it should also be noted that the ban on the use of substances belonging to the neonicotinoid class risks causing increased resistance to other insecticides, especially pyrethrinoids, if they are used as alternatives.

The exploration of the literature devoted to production systems not relying on neonicotinoids opens up opportunities in terms of research, sharing of guidelines and technical support. While non-chemical pest control methods are currently being or have been studied in research and technical institutes around the world, their potential effectiveness and practical implementation methods do not yet allow them to be made immediately operational.  To ensure effective control, the wide range of cultural control methods that are increasingly being developed in the context of agroecology therefore still need to be combined, which requires the more or less extensive rethinking of crop systems (diversification, use of sanitising plants and development of strategies combining what happens in and around the plot and on small territorial scales).

In addition, the use of chemical mediators, produced by plants in particular (e.g. repellents), seems very promising. The use of beneficial insects (parasitoids or predators) also offers solutions for more than 20% of the studied uses, particularly for protected crops. Research is being undertaken into other solutions, which should rapidly be developed.

ANSES therefore recommends speeding up the provision of effective alternative methods for crop protection and management that are safer for humans and the environment.