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In “Silent Spring”, Rachel Carson gave society a warning about the dangers of organochlorine insecticides such as DDT or dieldrin: “These sprays, dusts, and aerosols are now applied almost universally to farms, gardens, forests, and homes - non-selective chemicals that have the power to kill every insect, the "good" and the "bad", to still the song of birds and the leaping of fish in the streams, to coat the leaves with a deadly film, and to linger on in soil - all this, though the intended target may be only a few weeds or insects. Can anyone believe it is possible to lay down such a barrage of poisons on the surface of the earth without making it unfit for all life?.” The situation is not much different today. Wild pollinators and honeybees alike have been facing an increasingly toxic landscape since the introduction and rapid uptake of neonicotinoids in the late 1990s. Mining data from USDA, EPA, industry and California's pesticide use reporting system (the only one of it's kind), here's a snapshot of what bees are facing in the field:
- Over 2 million pounds of clothianidin, imidacloprid and thiamexotham (three neonicotinoids) are used in an average year.
- At least 143 million of our 442 million acres of cropland is planted with crops treated with one of three neonicotinoids: clothianidin, imidacloprid and/or thiamexotham.
- 83+ million of these acres are corn, upon which honeybees rely for core nutrition (corn is wind pollinated, it doesn't need bees for pollination, but its sheer abundance of pollen makes it a staple source of bee forage).

Imidacloprid is a systemic insecticide effective in controlling the exotic pest Adelges tsugae (hemlock woolly adelgid) in eastern hemlock (Tsuga canadensis) trees. Concerns over imidacloprid impacts on nontarget species have limited its application in southern Appalachian ecosystems. We quantified the movement and adsorption of imidacloprid in forest soils after soil injection in two sites at Coweeta Hydrologic Laboratory in western North Carolina. Soils differed in profile depth, total carbon and nitrogen content, and effective cation exchange capacity. We injected imidacloprid 5 cm into mineral soil, 1.5 m from infested trees, using a Kioritz soil injector. We tracked the horizontal and vertical movement of imidacloprid by collecting soil solution and soil samples at 1 m, 2 m, and at the drip line from each tree periodically for 1 yr. Soil solution was collected 20 cm below the surface and just above the saprolite, and acetonitrile-extractable imidacloprid was determined through the profile. Soil solution and extractable imidacloprid concentrations were determined by high-performance liquid chromatography. Soil solution and extractable imidacloprid concentrations were greater in the site with greater soil organic matter. Imidacloprid moved vertically and horizontally in both sites; concentrations generally declined downward in the soil profile, but preferential flow paths allowed rapid vertical movement. Horizontal movement was limited, and imidacloprid did not move to the tree drip line. We found a negative relationship between adsorbed imidacloprid concentrations and soil microarthropod populations largely in the low-organic-matter site; however, population counts were similar to other studies at Coweeta.

Most of us would not like to think we might be implicated in the decline of honeybees worldwide, or in the decreasing numbers of bumblebees, butterflies and farmland birds nearer home, but two scientific papers published at the end of last month suggest we are. The scientists’ findings about the effect of the latest generation of pesticides on bees and other pollinators mean we should all re-examine what we buy. For someone who, as concern has grown, has tried to keep a sense of proportion about the possible effects of a group of pesticides called neonicotinoids — nicotine-like substances that were introduced in the 1990s
— the sense of betrayal runs deep. I expect multinational pesticide companies to play down evidence they don’t like and to play up the importance of pesticides when it comes to feeding the world. I don’t expect the people we pay to protect our environment to operate complacently on the same assumptions. What we are talking about is nothing less than the poisoning of the countryside on a scale greater than Rachel Carson wrote about in Silent Spring, her classic exposure of the first generation of synthetic pesticides. Three million acres of Britain are treated with the new pesticides. Their true effects were missed by regulators despite the erection, under the European Union, of the greatest edifice of environmental legislation yet. No wonder an English scientist quoted in the normally cautious journal Science predicts that these two scientific papers will cause “an absolute firestorm”. The Xerces Society for Invertebrate Conservation recently published a review of research into the effects of neonicotinoid insecticides on bees, with recommendations for action (attached). Attached also is an article on the influence of Bayer Cropscience on Dutch policy makers (which appeared the magazine "Vrij Nederland" on April 4, 2012).

The coming together of a major problem and a leading problem-solver can be a significant moment, and we witnessed one such last week with the news that Professor Bob Watson is going to have a close personal look at the issue of neonicotinoids, the new nerve-agent pesticides, and their effect on bees and other pollinating insects. For Bob Watson is a towering figure, and that is the bigger significance: he is the world's leading expert on policy responses to global change, on what we should do about climate change, the loss of wildlife, the destruction of ecosystems and the need to feed a world of nine billion people – and in particular, on how we should respond as a society when all these difficulties come together, as they are now. On Monday, the Defra website carried its own story headlined: "Myth Busters", saying the Independent story was not true. It said: "The truth: Bob Watson did not order a review of the evidence......he asked to receive regular updates on new research into the possible effects on insects which are not the target species of pesticides." This is what Bob Watson told me on Friday: "The real Defra position is the following. We will absolutely look at the University of Stirling work, the French work, and the American work that came out a couple of months ago. We must look at this in real detail to see whether or not the current British position is correct or is incorrect." If that's not a review of the evidence, what is? The Xerces Society for Invertebrate Conservation recently published a review of research into the effects of neonicotinoid insecticides on bees, with recommendations for action (attached).

Sudden losses of bees have been observed in spring during maize sowing. The death of bees has been correlated with the use of neonicotinoid-coated seed and the toxic particulates emitted by pneumatic drilling machines. The contamination of foragers in flight over the ploughed fields has been hypothesized. The airborne contamination has been proven, both with bees inside fixed cages around the field and in free flight near the driller. A new trial involving mobile cages has been established and consists of making rapid passes with single bees inside cages fixed to an aluminium bar. The bar was moved by two operators at different distances from the working drilling machine. A single pass was shown as sufficient to kill all the bees exposed to exhaust air on the emission side of the drill, when bees were subsequently held in high relative humidity. The extent of toxic cloud around driller was evaluated at the height of 0.5, 1.8 and 3.5 m and proved to be about 20 m in diameter, with an ellipsoidal shape. The shape may be influenced by working speed of the drill and environmental parameters, and is easily shown by adding talc powder to the seed in the machine hopper. A new driller equipment was evaluated consisting of two tubes inclined towards the soil that direct the exhaust air towards the ground. The survival rate of the bees was not substantially increased using the modified drill and was lower than 50%. Chemical analyses show up to 4000 ng of insecticide in single bees with an average content around 300 ng. Similar quantities were observed at increased distances from the modified or unmodified drillers. This new evaluation of bee mortality in the field is an innovative biological test to verify the hypothetical efficiency (or not) of driller modifications.

A few days ago the Salt Lake Tribune’s front page headline declared, "Highest rate in the nation, 1 in 32 Utah boys has autism." This is a national public health emergency, whose epicenter is Utah, Gov. Herbert. A more obscure story on the same day read: "New pesticides linked to bee population collapse." If you eat food, and hope to do so in the future, this is another national emergency, Pres. Obama. A common denominator may underlie both headlines.

Dear Tom Vilsac,
I am writing you as a scientist and as an agribusiness-man who has used both aldicarb and neonicotinoid systemic insecticides commercially and who has suffered losses of honey bees foraging on treated crops. I have had personal experience using systemic insecticides on a commercial scale having been the owner of several agricultural businesses in the Northeast USA.

In the 1990's on two separate occasions I witnessed complete colony collapse of my bees. The first incident losing over a half a million bees that foraged on two acres of potted perennials which were treated with Imidacloprid. The second time I lost several hives to a neighbors 'Grubex' 1 control treated clover lawn. After seeing the total collapse of the hives we stopped using Imidacloprid and all other systemic pesticides. I no longer use any pesticides, or biocides and now practice sustainable organic methods of agriculture.

Species belonging to the family of the Apidae such as the bumblebee Bombus terrestris are widely used for the pollination of greenhouse crops. However, to obtain satisfactory yields growers need to protect their crops against plant diseases and pests who are up until today still mainly controlled by chemical pesticides. Consequently exposure to pesticides during foraging is not unlikely. To assess detrimental effects (lethal and sublethal effects) on the vector following pesticide exposure the classic toxicity test using microcolonies can be applied. However, beside toxicity pesticides are known to induce sublethal effects on the foraging behaviour. In this context, a foraging behaviour test was developed allowed to assess the impact on the foraging activity by use of two endpoints drone production and nest development.