4.8 Pesticides and pollinators
A growing controversy on the causes of bee decline (sometimes referred to as ‘colony collapse disorder’) over recent years has now resulted in an EU moratorium on the neonicotinoids (NNI): clothianidin, imidacloprid and thiamethoxam [1] (although cocoa is pollinated by midges not by bees).
This forms an “Ongoing review of active substances” by the EU and a possible re-evaluation of fipronil is also of interest to cocoa producers. [September 2025 update: Fipronil is no longer approved for outside use in plant protection in Europe due to concerns over its effects on bees in particular. There are some import tolerances in place for fipronil in some commodities but not for cocoa]
The restriction on clothianidin, imidacloprid and thiamethoxam followed risk assessments by the European Food Safety Authority (EFSA) [2], which “concluded the following for all three substances:
- Exposure from pollen and nectar. Only uses on crops not attractive to honeybees were considered acceptable.
- Exposure from dust. A risk to honeybees was indicated or could not be excluded, with some exceptions, such as use on sugar beet and crops planted in glasshouses, and for the use of some granules.
- Exposure from guttation. The only risk assessment that could be completed was for maize treated with thiamethoxam. In this case, field studies show an acute effect on honeybees exposed to the substance through guttation fluid.
EFSA’s conclusions contain tables listing all authorised uses for seed treatment and as granules of the three substances in the EU. Subsequently, a restriction of the use of the 3 NNI was adopted by the Commission.
The move followed votes on 15 March 2013 by Member States' experts meeting at a Standing Committee on the Food Chain and Animal Health and on 29 April 2013 at an Appeal Committee where EU Member States did not reach a qualified majority – either in favour or against the Commission's proposal.
The UK was one of the states voting against, influenced by a DEFRA evaluation of studies [3] purporting to link the 3 NNI to bee harm: this provides a useful literature search and found that much of the evidence was based on laboratory work and would not normally occur in field scenarios.
Prof. J Beddington suggested the EU was in danger of failing to understand risk saying: “This potentially legitimises an overly precautionary approach in the absence of scientific evidence showing any risk”.
[September 2025 update: clothianidin, imidacloprid, thiamethoxam and thiacloprid are no longer approved for use in the UK due to concerns over pollinator and/or human health, though emergency approvals for special uses have been granted in recent years. However, a recent policy paper (December 2024) sets out the strategy to ending the use in England completely due to concerns over risks to pollinator populations]
In the USA, the Environmental Protection Agency (EPA) similarly has been petitioned by activist groups, including beekeepers, to likewise ban NNIs.
A USDA report [4] describes several possible causes of national decline in honeybees, including: habitat loss, poor diet, diseases, parasites (especially Varroa destructor) and pesticide exposure (including sub-lethal effects that affect bee behaviour).
Research so far points to a combination of these factors: which may be responsible for the 30% decline in honeybees annually since 2006.
As in the EU, engineering controls can help minimise off-site dust movement from treated seeds, together with other standard good agricultural practices.
Registration Authorities in cocoa growing countries should remain vigilant and likewise maintain their ongoing review of registered pesticide products appropriate to 21st century needs. However, as with other crops, policymakers must also foster a strategy for ‘sustainable intensification’: in this case maintaining a diversity of appropriate and efficacious range of active substances in various (>2) modes of action for control of key cocoa pests.
Those concerned with pesticide policy in cocoa should be aware that NNIs and fipronil are now very much ‘in the firing line’ of environmental activists and that their regulatory status in Europe and N. America is subject to change. Short and medium-term strategies to manage these issues are required now. Imidacloprid-based insecticides in particular are now widely marketed in cocoa growing countries and MRL violation cases appear to be increasing.
Attention to label rates (and clarity) for NNIs, field application practices and pre-harvest intervals in cocoa are clearly a priority issue for registration and extension staff.
