Insecticides

In its response, published today, the Government misrepresents its own science in deciding not to implement recommendations to save pollinators from neonicotinoid pesticides. In March, following extensive evidence gathering, the Environmental Audit Committee published its ‘Pollinators and Pesticides’ report, concluding that neonicotinoids are having an “especially deleterious impact on insect pollinators”. However, Government has decided that it:-
• Will not improve the transparency of the regulatory process so that studies done by pesticide companies are in the public domain, stating that “the cost of publishing this information, even on the internet, would be substantial”.
• Will not raise the UK’s environmental protection standards by including other pollinators in the national risk assessment process.
• Will not ban all amenity and garden use of neonicotinoids.
• Will not set up a pollinator monitoring scheme - although this is not ruled out for the future.

Rachel Carson described her fears about the use of systemic insecticides like neonicotinoids 50 years ago when she wrote Silent Spring. Now, we are witnessing first-hand as her predictions become a reality: “The world of systemic insecticides is a weird world, surpassing the imaginings of the brothers Grimm… It is a world where the enchanted forest of the fairy tales has become the poisonous forest in which an insect that chews a leaf or sucks the sap of a plant is doomed. It is a world where a flea bites a dog, and dies because the dog’s blood has been made poisonous, where an insect may die from vapors emanating from a plant it has never touched, where a bee may carry poisonous nectar back to its hive and presently produce poisonous honey.” Compounding the problem is a shift away from integrated pest management (IPM) and agroecological practices, systems that, to varying degrees, mitigate the indiscriminate use of toxic chemicals. Industrial agriculture practices rely on pesticides whether they are needed or not, thus putting an unsustainable load of chemicals into the environment and adding weight to Carson’s frightening predictions. As one report notes, “Over the last 20 years or so, the shift in pest management has moved away from reactive to prophylactic. Now many fungicides, pesticides and herbicides are applied to the seeds before sowing. Application of the chemical before pest damage has occurred often involves routine spraying and pre-emptive treatments.”

Environment Canada had conducted a water study in Saskatchewan on canola/ oilseed rape fields both last year and this year. They found Clothianidin in a large number of agricultural sites where Canola (oilseed rape) had been planted in 2011. The concentrations of residual Clothianidin in puddles and ditches were almost one thousand times the LD50 required to kill bees.Clothianidin concentrations ranged from 5.1 to 2280 ng/L. The average Clothianidin contamination of water was 162.9 ng/L. The scientifc presentation is attached.

Neonicotinoid insecticides have adverse effects not only on bees but also on freshwater invertebrates. An Eawag study published today in the journal PLOS ONE (Public Library of Science) shows that at least one of the insecticides in this class also has toxic effects on freshwater invertebrates. In this study, native freshwater shrimps (gammarids) were exposed to pulsed high and to constant low concentrations of imidacloprid. Peak concentrations typically occur when rain falls on farmland during or shortly after the application of insecticides; these soluble but persistent substances can then enter surface waters via runoff. Interestingly, pulses lasting no more than a day proved less harmful to the organisms than concentrations that were much lower but persisted for several days or weeks. While organisms transferred to clean water after pulsed exposure recovered relatively rapidly, constant exposure led to starvation after 2 to 3 weeks. This was because the organisms' mobility and feeding behaviour was impaired by the neurotoxin.

Die EU-Kommission irrt - diesen Standpunkt vertreten die Chemiekonzerne Bayer und Syngenta zum „Neonicotinoid-Verbot“. Die beiden Unternehmen wehren sich deshalb. Die Pflanzenschutz- und Saatgut-Tochter Bayer CropScience hat bereits Mitte August eine Klage eingebracht. Am Dienstag der letzten Augustwoche teilte auch Syngenta mit, rechtlich gegen die Entscheidung vorzugehen. Die Bestimmung der Kommission habe sich auf ein "fehlerhaftes Verfahren sowie eine ungenaue und unvollständige Prüfung" durch die EU-Behörde für Lebensmittelsicherheit (EFSA) gestützt und sei zudem nicht von allen Mitgliedstaaten unterstützt worden, teilte Syngenta dazu mit. Im April hatte sich eine Mehrheit der Mitgliedstaaten, darunter Deutschland, für das Verbot von drei Neonicotinoiden ausgesprochen. Die Wirkstoffe stellen nach Angaben der EU ein Risiko für die Bienen dar.

Two agrochemical companies are fighting back against an E.U.-wide ban on three common neonicotinoid pesticides. Syngenta Crop Protection, which manufactures and sells one of the compounds in Europe, announced yesterday that it has brought a legal case earlier this month before the Court of Justice of the European Union, based in Luxembourg. Bayer CropScience, another producer, has done the same, a company spokesperson tells ScienceInsider. In April, the European Commission decided to introduce a 2-year moratorium on the compounds—clothianidin, imidacloprid, and thiamethoxam—following reports by the European Food Safety Authority (EFSA) saying the substances pose an "acute risk" to honey bees essential to farming and natural ecosystems. The Dutch toxicologist Henk Tennekes infers that pesticide producers are ignoring compelling evidence implicating neonicotinoid pesticides in insect decline.

Regulatory decisions based on current risk approaches are flawed simply because the science underpinning the risk of chemicals is inappropriate in many cases. A fundamental problem is to use one methodology for all compounds, irrespective of their toxic mode of action in organisms. According to the theories of Druckrey and Küpfmüller, the character of a poison is primarily determined by the reversibility of critical receptor binding. Chemicals showing irreversible or slowly reversible binding to specific receptors will produce cumulative effects with time of exposure, and whenever the effects are also irreversible (e.g. death) they are reinforced over time; these chemicals have time-cumulative toxicity.This concept was validated by Druckrey and co-workers with genotoxic carcinogens, the action of which is described by what is now known as the Druckrey-Küpfmüller equation: c x t˄n = constant, where c = exposure concentration, t = median time to effect, and n is an exponent > 1, which reflects reinforcement of the effect over time. Using data generated by Sanchez-Bayo, Tennekes demonstrated that the Druckrey-Küpfmüller equation also described the toxicity of (non-genotoxic) neonicotinoid insecticides to arthropods. This discovery showed that the theories of Druckrey and Küpfmüller were generally applicable in toxicology and, perhaps even more importantly, that risk assessment procedures needed to be revised, because the risks of time-cumulative toxins had been seriously underestimated.