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UK government adviser said to have ordered review of neonicotinoid insecticides but Defra denies this

The official British government position has been that the neonicotinoid insecticides are safe when used correctly – but Professor Robert Watson, the chief scientific adviser at the Department for Environment, Food and Rural Affairs (Defra), has now initiated his own inquiry, The Independent revealed, because of concerns about the alleged effects on bees. However, Defra denied this and states that Bob Watson did not order a government “review” of the safety of neonicotinoid pesticides. The decline in populations of bees and other pollinators remains a major concern, and he asked to receive regular updates on new research into the possible effects on insects which are not the target species of pesticides. Defra had considered all recent research on neonicotinoids, including an as yet unpublished study conducted by US Department of Agriculture researcher, Jeffrey Pettis and a second similar study by Cedric Allaux from the French National Institute for Agricultural Research, which suggested that the neonicotinoid insecticide, imidacloprid, made honey bees more susceptible to disease caused by a parasite, nosema. "We have concluded that the studies do not present any new evidence," the spokesman said. "The UK has a robust system for assessing risks from pesticides and all the evidence shows neonicotinoids do not pose an unacceptable risk when products are used correctly. We will not hesitate to act if presented with any new evidence."

The catastrophic decline of bumblebees

In North America there are more than 5,000 species of native bees of which 60 kinds of bumblebees occupy habitats ranging from the Arctic Circle to the Sonoran Desert. Bumblebees, like the beleaguered honeybees, are in trouble; their populations are crashing. A three year study, headed up by the University of Illinois has documented four species of U.S. bumblebees (Bombus occidentalis, Bombus pensylvanicus, Bombus affinis and Bombus terricola) declining by up to 96 percent and that their geographic ranges have contracted from between 23 percent to 87 percent, some within just the past two decades.

New method for rearing bee larvae in the laboratory

Ecologists from the University of Wurzburg, Germany have developed a better way of rearing bee larvae in the laboratory. The current method of rearing bees in the laboratory has major drawbacks. It involves a process known as "grafting", where the tiny first instar bee larvae around 1mm long are collected using feathers, brushes or needles. As well as being time consuming and demanding considerable skill, the mechanical stress involved in handling causes mortality among the tiny larvae. To avoid handling the larvae, the researchers allowed honey bee queens to lay eggs directly into an artificial plastic honeycomb about the size of a cigar box. The plastic honeycomb is widely used by professional honey bee queen breeders, and by using in the laboratory the team found rearing bee larvae much easier and more successful.

What the EPA knew about clothianidin in 2003 when conditional registration was granted

The U.S. EPA assessed the potential risks of clothianidin in 2003, when conditional registration was granted, as follows: "Clothianidin is highly toxic to honey bees on an acute contact basis. It has the potential for toxic chronic exposure to honey bees, as well as other nontarget pollinators, through the translocation of clothianidin residues in nectar and pollen. In honey bees, the effects of this toxic chronic exposure may include lethal and/or sub-lethal effects in the larvae and reproductive effects in the queen. The fate and disposition of clothianidin in the environment suggest a compound that is a systemic insecticide that is persistent and mobile, stable to hydrolysis, and has potential to leach to ground water, as well as runoff to surface waters. "

EU 'should investigate link between pesticides and bee decline'

The EU is being urged to carry out more research into the effects of pesticides on Europe's bee population. MEPs, scientists and EU officials came together in the European parliament on Wednesday 23 March 2011 to discuss the potential risks of plant protection products on bees. Speaking at the event, ALDE deputy Chris Davies called on the EU to invoke the precautionary principle in relation to certain pesticides, which could result in their withdrawal from the market were they found to constitute a health risk.

EFSA identifies the toxicity of neonicotinoids to bees (and other non-target organisms such as amphibians) as a critical area of concern

The European Food Safety Authority (EFSA), which carries out risk assessment on plant protection products, is currently reviewing recent scientific literature with regard to the effects of pesticides, and in particular of neonicotinoids, on bees. In its conclusions on imidacloprid and fipronil, EFSA has identified the toxicity to bees (and other non-target organisms) as a critical area of concern.

Impact of neonicotinoid insecticides on natural enemies in greenhouse and interiorscape environments

The neonicotinoid insecticides imidacloprid, acetamiprid, dinotefuran, thiamethoxam and clothianidin are commonly used in greenhouses and/or interiorscapes (plant interiorscapes and conservatories) to manage a wide range of plant-feeding insects such as aphids, mealybugs and whiteflies. However, these systemic insecticides may also be harmful to natural enemies, including predators and parasitoids. Predatory insects and mites may be adversely affected by neonicotinoid systemic insecticides when they: (1) feed on pollen, nectar or plant tissue contaminated with the active ingredient; (2) consume the active ingredient of neonicotinoid insecticides while ingesting plant fluids; (3) feed on hosts (prey) that have consumed leaves contaminated with the active ingredient. Parasitoids may be affected negatively by neonicotinoid insecticides because foliar, drench or granular applications may decrease host population levels so that there are not enough hosts to attack and thus sustain parasitoid populations. Furthermore, host quality may be unacceptable for egg laying by parasitoid females. In addition, female parasitoids that host feed may inadvertently ingest a lethal concentration of the active ingredient or a sublethal dose that inhibits foraging or egg laying.

A meta-analysis of experiments testing the effects of a neonicotinoid insecticide (imidacloprid) on honey bees

Honey bees provide important pollination services to crops and wild plants. The agricultural use of systemic insecticides, such as neonicotinoids, may harm bees through their presence in pollen and nectar, which bees consume. Many studies have tested the effects on honey bees of imidacloprid, a neonicotinoid, but a clear picture of the risk it poses to bees has not previously emerged, because investigations are methodologically varied and inconsistent in outcome. In a meta-analysis of fourteen published studies of the effects of imidacloprid on honey bees under laboratory and semi-field conditions that comprised measurements on 7073 adult individuals and 36 colonies, fitted dose–response relationships estimate that trace dietary imidacloprid at field-realistic levels in nectar will have no lethal effects, but will reduce expected performance in honey bees by between 6 and 20%. Statistical power analysis showed that published field trials that have reported no effects on honey bees from neonicotinoids were incapable of detecting these predicted sublethal effects with conventionally accepted levels of certainty. These findings raise renewed concern about the impact on honey bees of dietary imidacloprid.

Interactions between Nosema microspores and a neonicotinoid weaken honeybees (Apis mellifera)

Global pollinators, like honeybees, are declining in abundance and diversity, which can adversely affect natural ecosystems and agriculture. Therefore, we tested the current hypotheses describing honeybee losses as a multifactorial syndrome, by investigating integrative effects of an infectious organism and an insecticide on honeybee health. We demonstrated that the interaction between the microsporidia Nosema and a neonicotinoid (imidacloprid) significantly weakened honeybees. This provides the first evidences that interaction between an infectious organism and a chemical can also threaten pollinators, interactions that are widely used to eliminate insect pests in integrative pest management. An independent American study by Pettis et al. recently confirmed these results.

Are Regulators Doing Enough to Prevent Bee Die-Offs?

Beekeepers across the United States have reported higher than average overwintering losses since at least 2006. Scientists are investigating various pathogens, parasites, environmental stresses – including the impacts of pesticides – and management issues as likely contributors to the widespread die-offs. While scientists and beekeepers have been puzzling over the cocktail of factors that could be driving the die-offs, Colorado beekeeper Tom Theobald suspects that a group of pesticides called neonicotinoids, which attack insects’ central nervous systems, paralyzing and killing them, play a key role. To date, much of the research into the potential effects of neonicotinoids on honeybees has focused on clothianidin’s cousin and Bayer’s top selling seed treatment, imidacloprid – sold under the trade name Gaucho – which works in a similar way. Attached is an article on the influence of Bayer Cropscience on Dutch policy makers (which appeared the magazine "Vrij Nederland" on April 4, 2012).