Insecticides

Current bee population declines and colony failures are well documented yet poorly understood and no single
factor has been identified as a leading cause. The evidence is equivocal and puzzling: for instance, many
pathogens and parasites can be found in both failing and surviving colonies and field pesticide exposure is
typically sublethal. Here, we investigate how these results can be due to sublethal stress impairing colony
function. We mathematically modelled stress on individual bees which impairs colony function and found
how positive density dependence can cause multiple dynamic outcomes: some colonies fail while others
thrive. We then exposed bumblebee colonies to sublethal levels of a neonicotinoid pesticide. The dynamics
of colony failure, which we observed, were most accurately described by our model. We argue that our
model can explain the enigmatic aspects of bee colony failures, highlighting an important role for sublethal
stress in colony declines.

Pesticides have been linked to Parkinson’s disease, declines in cognitive performance, developmental disorders, and attention-deficit/hyperactivity disorder in children. Their application has also been tied to environmental issues, such as the collapse of honeybee colonies and the development of resistant pests and weeds. But we know surprisingly little about population-wide health effects of the low doses that are in the foods we eat every day, panelists at the Harvard School of Public Health said Thursday. “We can’t tell for sure if you eat a bowl of salad today for lunch if it will lead to cancer in 10 to 20 years,” said Chensheng Lu, an associate professor of environmental exposure biology at the Harvard School of Public Health. Lu, whose recent research has tracked the mysterious collapse of honeybee colonies to a class of pesticides called neonicotinoids, said that broad studies on the effects of pesticide residue in foods are difficult to do. Funding is hard to attract because there isn’t a specific health impact being investigated. Also, there are daunting challenges to designing a scientifically valid study, stemming from the fact that so much of the population has been raised on foods treated with chemicals.

Il Centro di Riferimento Tecnico per l’Apicoltura Problematiche Ambientali e Nutrizionali di Unaapi ha sviluppato negli anni una più che proficua ollaborazione con tutti gli enti, soggetti istituzionali e scientifici che si sono variamente impegnati per rimediare alle cause che provocano il collasso di api e impollinatori. Vai riconosciuta alla ricerca scientifica italiana – perché significativamente pubblica e non condizionata? - una notevole capacità di monitoraggio e d’indagine. Grazie anche all’insieme di ricerche italiane si sono affermate alcune semplici, ma determinanti, modalità di studio, quali: l’insensatezza della traslazione all’alveare della dose letale 50 manifestata dalle singole api; la distinzione fra mortalità invernali e in stagione attiva; l’impatto ambientale della contaminazione in epoca di semina con concianti sistemici; la considerazione della possibilità che sia: “la goccia prodotta dall’uomo che fa traboccare il vaso”; le variegate vie di posizione “abitualmente” non considerate ecc… Il CRT Unaapi ha quindi ritenuto indispensabile proporre una disamina dello stato delle conoscenze sui comprovati e possibili effetti dei pesticidi sulle api, per:
• Denunciare infondatezza e falsità delle rassicurazioni sulla: “certa assenza di conseguenze”.
• Evidenziare quanti e quali sono gli aspetti non considerati rispetto ai possibili effetti dei pesticidi (puntuali o
ancor peggio: cronici) su api, impollinatori e vivente.
• Invitare apicoltori e cittadinanza tutta ad andare oltre la vaga lamentela, documentandosi adeguatamente.
Ringrazio i ricercatori che hanno redatto tale imponente e istruttiva, complessa ma fruibile, rassegna. A quanti si misureranno con la lettura l’auspicio di far tesoro di tale mole di accertamenti scientifici…

A very interesting paper has been issued under the aegis of the UK Royal Society, which however seems highly selective and biased in its ‘interpretations’. While this ‘appears’ to be a neutral assessment of the existing evidence on neonicotinoids and bee deaths, it is in my opinion a government/ science establishment project designed to justify/ bolster the UK government’s position. The involvement of Tjeerd Blacquiere from Wageningen in Holland makes one immediately suspect a rat - as does the involvement of anyone from Rothamsted Research - whose so-called ’scientists’ have served as the shock-troops for the advancement of GM technology, systemic pesticides and the industrialisation of farming in the UK. There are two scientists here from NERC -funded (National Environmental Research Council) research bodies; this is synonymous with UK government. The paper will undoubtedly be used to justify the UK government’s continued support for neonics and for their opposition to a Europe-wide ban.

This spring most Canadian corn and soybean growers will be planting another crop of pesticide-coated seeds, even as researchers raise new warnings that the practice may have deadly side effects for bees and other wildlife. The heated debate around the use of the neonicotinoid-coated seeds, developed by Bayer CropScience and introduced here about a decade ago, has divided farmers, beekeepers and scientists, and turned Canada into a kind of environmental battlefront.