http://smallbluemarble.org.uk/wp-content/uploads/2012/11/Wildlife-Trusts-Neonicotinoid-position-statement-FINAL-October-2012.pdf
The Royal Society of Wildlife Trusts (RSWT) operates as an umbrella body for the 47 individual Wildlife Trusts, covering the whole of the UK.
ABSTRACT
The Wildlife Trusts’ position
1. There is a growing body of evidence that shows that neonicotinoids have a detrimental effect at sub-lethal doses on insect pollinators. For this reason, The Wildlife Trusts believe that until it
can be categorically proven that neonicotinoids are not adversely impacting pollinator
populations, and by extension ecosystem health, Government should adopt the precautionary
principle and place a moratorium on their use on all outdoor crops.
Background
2. Since their introduction in 1991, there has been a growing concern that neonicotinoid
insecticides could be harmful to insect pollinators at sub-lethal doses. Neonicotinoids have been cited as a contributory factor in Colony Collapse Disorder and recent research regarding their effects on bee foraging behaviour appears to substantiate this.
3. Insect pollinators provide a vital ecosystem service to the UK’s farmers and fruit growers. It is estimated a collapse in pollinators would cost the UK economy c. £1.8 billion per year.
4. Most plant communities rely on pollinating insects to reproduce and therefore spread (apart from species such as grasses which are wind pollinated). They also form a vital part of the food chain for other species such as birds, reptiles and amphibians. It follows that any insecticide that drastically reduces pollinator numbers will have effects beyond the agricultural sector and will ultimately affect the health and function of entire ecosystems.
5. The registration documents/fact sheets for the individual neonicotinoids state that they are toxic or highly toxic to bees; either acutely, or chronically via pollen and nectar
6. However, the manufacturers of the insecticides claim that neonicotinoids do not cause direct bee mortality at small doses. Defra is of the view that the body of evidence assessed so far supports the conclusion that neonicotinoids do not threaten honey bee populations if properly used. The Scottish Government, which has an advisory role in the UK’s pesticide regulation, is adopting the same approach.
What are neonicotinoids?
7. Neonicotinoids are a group of systemic insecticides routinely used in modern farming systems to help protect crops such as oilseed rape, maize, sugarbeet, sunflowers and potatoes from sap sucking insects such as aphids and other insect herbivores.
8. In 1991, the first nicotine-based insecticide, imidacloprid (Gaucho®), was introduced into the USA by Bayer CropScience. It was licensed in Europe in 1994.
9. Other neonicotinoids include clothianidin, acetamiprid, thiacloprid, thiamethoxam, dinotefuran and nitenpyram.
How neonicotinoids work
10. The active chemical works by interfering with the transmission of stimuli in an insect’s nervous system. More specifically, the chemical has an affinity for nicotinic acetylcholine receptors which are important neuro-transmitter Receptors. The binding of the chemical with these receptors results in paralysis and death of the insect. This neural pathway is more abundant in insects than mammals and birds making the chemical much more toxic to insects. However, research has shown that neonicotinoids do act on mammalian pathways and could damage human health
11. Neonicotinoids bind irreversibly [to brain synapses], causing permanent damage. This damage is cumulative, meaning that toxic effects are produced in a time-dependent manner, no matter how low the
level of exposure
Wider environmental impacts
12. Neonicotinoids could have wider environmental effects. They are water soluble and mobile in soil, where they are also very persistent. Research has shown major contamination of Dutch surface water with imidacloprid, which has been linked to declines in invertebrate-dependent bird species
Colony Collapse Disorder
18. Colony collapse disorder (CCD) is a recent, widespread phenomenon affecting honey bee
colonies in the Northern hemisphere. It is characterized by a sudden disappearance of honey
bees from the hive. The syndrome is mysterious in that the there are often no corpses found, and although there are often many disease organisms present, no outward signs of disease, pests, or parasites exist. Multiple causes of CCD have been proposed, such as combinations of pesticides, pathogens, parasites and natural habitat degradation.
19. In some European countries, increasing concern regarding the connection between CCD and
neonicotinoids has led to a partial or full ban of some neonicotinoids. As early as 1994, French beekeepers noticed that over the course of a few days, after sunflowers had bloomed, a
substantial number of their hives would collapse because the worker bees flew off and never returned, leaving the queen and immature workers to starve. French beekeepers believed the
root cause was the new insecticide Gaucho®, an imidacloprid based neonicotinoid which was
being applied to sunflowers for the first time. It took French beekeepers nearly 10 years to get imidacloprid banned in France for use on sunflowers and maize. Other European countries that have a partial or full ban of some of neonicotinoid products include Germany, Italy and Slovenia.