Neue Studie belegt den Zusammenhang zwischen Pestiziden und Immunsystemschwäche.
Pesticide exposure in honey bees results in increased levels of the gut pathogen Nosema
Jeffery*S.*Pettis1*, Dennis*vanEngelsdorp2, Josephine*Johnson3 and Galen*Dively4
(1)* USDA-ARS Bee Research Laboratory, Beltsville, MD, USA
(2)* Department of Entomology, University of Maryland, College Park, MD, USA
(3)* Department of Toxicology, University of Maryland Baltimore, Baltimore, MD, USA
(4)* Department of Entomology, University of Maryland, College Park, MD, USA
Received: 1*May*2011**Revised: 25*December*2011**Accepted: 31*December*2011**Published online: 13*January*2012
Communicated by: Sven Thatje
Global pollinator declines have been attributed to habitat destruction, pesticide use, and climate change or some combination of these factors, and managed honey bees, Apis mellifera, are part of worldwide pollinator declines. Here we exposed honey bee colonies during three brood generations to sub-lethal doses of a widely used pesticide, imidacloprid, and then subsequently challenged newly emerged bees with the gut parasite, Nosema spp. The pesticide dosages used were below levels demonstrated to cause effects on longevity or foraging in adult honey bees. Nosema infections increased significantly in the bees from pesticide-treated hives when compared to bees from control hives demonstrating an indirect effect of pesticides on pathogen growth in honey bees. We clearly demonstrate an increase in pathogen growth within individual bees reared in colonies exposed to one of the most widely used pesticides worldwide, imidacloprid, at below levels considered harmful to bees. The finding that individual bees with undetectable levels of the target pesticide, after being reared in a sub-lethal pesticide environment within the colony, had higher Nosema is significant. Interactions between pesticides and pathogens could be a major contributor to increased mortality of honey bee colonies, including colony collapse disorder, and other pollinator declines worldwide.
Es wurde Imidacloprid in so kleinen Dosierungen gefüttert, daß es nicht mehr nachzuweisen war! Und die Bienen erkrankten danach SIGNIFIKANT häufiger, wenn sie NOSEMA ausgesetzt waren!
Damit sind die SUBLETALEN Wirkungen auf Honigbienen von Imidacloprid bewiesen.
Bitte jemand übersetzen, wenn er Zeit findet.
Elevated levels of the fungicide chlorothalonil in honey bees have been associated with “entombed pollen” which is linked with increased risk of colony mortality (vanEngelsdorp et al. 2009b). The call for a reevaluation of pesticide test protocols required for the registration of products is not new (Colin et al. 2004; Halm et al. 2006). These proposed new standards utilize the Predicated No Effect Concentration which is determined using chronic and acute toxicity data and not potentially indirect effects of pesticide exposure, such as increased susceptibility to pathogens. With the wide variety of pesticides that have been documented in failing beehives (Mullen et al. 2010), it is imperative that we understand both the synergistic effects these compound may have and the interactions with other variables, like pathogens, involved in bee health. We suggest new pesticide testing standards be devised that incorporate increased pathogen susceptibility into the test protocols. Lastly, we believe that subtle interactions between pesticides and pathogens, such as demonstrated here, could be a major contributor to increased mortality of honey bee colonies worldwide.