3 April 2016
In 2013 the EU introduced a temporary ban on the use of neonicotinoid pesticides because of worries about the link between their use and a decline in the populations of bees and other pollinating insects. Even back then the UK government tried to block the ban and has continued to allow the use of neonicotinoids in some areas on a temporary basis – the latest in July 2015 when their application was allowed for 120 days on some of the UK’s oilseed rape crops; mainly in Suffolk.
Neonicotinoids are among a class of pesticides known as insecticides; that is they protect plants from insect attack by poisoning the insects. There are several reasons why we should be worried about the use of these particular pesticides:
•They are ‘broad spectrum’ pesticides. This means that they affect many different types of insects and other invertebrates, not just the target pest species. The chemicals often harm non-target species such as pest predators and pollinators.
•They are ‘systemic’ pesticides, meaning they are absorbed and transported throughout the whole plant, including the pollen and nectar. The toxin remains active for several weeks, protecting the plant from insect attack. This was one of the reasons why they were originally thought of as more ‘environmentally friendly’ because their persistency in the crop meant that fewer pesticide applications were needed. However, because they remain in the crop and in the soil this makes them more likely to affect non-target species.
•Neonicotinoids act on the central nervous system of insects. They affect a particular neural pathway, attaching to an important enzyme and causing paralysis and eventual death. Mammals have considerably fewer of these specific neural pathways, so are not normally affected. Bees, however, have more than other insects and so are more highly susceptible to the toxin.
•Because neonicontinoids are effective at low concentrations they can be applied to crops in very small doses; in grams rather than kilograms per hectare – another reason why they were originally considered more environmentally friendly than older types of insecticide. But this is another reason why they are posing such a threat to bees and other insects.
•The environmental risk assessment tool that is still being used to evaluate the risks of pesticides to bees is out of date and not fit for purpose. It was developed for the older types of pesticides which were designed for spraying foliage and not for the newer systemic pesticides like neonicotinoids. The risk assessment also does not address the fact that neonics are highly persistent throughout plants and soil (once applied) and does not take into account the possibility that this increases their potential to affect a wider range of invertebrate species.
•The present risk assessment relies almost entirely on an outdated method of measuring toxicity. It uses the LD50 test, which simply gives a ‘dead or alive’ result and fails to take into account any sub-lethal or chronic lethal effects.
What you can do:
Please write or email the Defra Minister and your own MP urging them to vote to retain the EC restrictions on neonicotinoids. You can get more information from the Pesticide Action Network UK at www.pan-uk.org
Jane Feaviour-Clarke (Fenland Green Party)
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