Fungiciden

Pesticide coated seeds are commonly used in agriculture, and may be an important source of food for some birds in times of scarcity, as well as a route of pesticide ingestion. We tested the lethal and sub-lethal effects of treated seed ingestion by the red-legged partridge (Alectoris rufa), a game bird of high socio-economic value
in Spain. One year-old partridges (n = 42 pairs) were fed for 10 days in spring (prior to breeding) with wheat treated with difenoconazole (fungicide), thiram (fungicide) or imidacloprid (insecticide), using two doses for each pesticide (the one recommended, and its double to represent potential cases of abuse of pesticides). We investigated the direct and indirect effects on the body condition, physiology, immunology, coloration and subsequent reproduction of exposed partridges. For the latter, eggs were collected, measured and incubated and the growth and survival of chicks were monitored. Thiram and imidacloprid at high exposure doses produced mortalities of 41.6 and 58.3 %, respectively. The first death was observed at day 3 for imidacloprid and at day 7 for thiram. Both doses of the three pesticides caused sublethal effects, such as altered biochemical parameters, oxidative stress and reduced carotenoid-based coloration. The high exposure doses of
imidacloprid and thiram also produced a decrease in cellular immune response measured by the phytohemagglutinin test in males. Bearing in mind the limitation of the small number of surviving pairs in some treatments, we found that the three pesticides reduced the size of eggs and imidacloprid and difenoconazole also reduced the fertilization rate. In addition, both thiram and imidacloprid reduced chick survival. These experiments highlight that the toxicity of pesticide-treated seeds is a factor to consider in the decline of birds in agricultural environments.

The quality and quantity of the data about the risk posed to humans by individual pesticides vary considerably. Unlike obvious birth defects, most developmental effects cannot be seen at birth or even later in life. Instead, brain and nervous system disturbances are expressed in terms of how an individual behaves and functions, which can vary considerably from birth through adulthood. In this article I challenge the protective value of current pesticide risk assessment strategies in light of the vast numbers of pesticides on the market and the vast number of possible target tissues and end points that often differ depending upon timing of exposure. Using the insecticide chlorpyrifos as a model, I reinforce the need for a new approach to determine the safety of all pesticide classes. Because of the uncertainty that will continue to exist about the safety of pesticides, it is apparent that a new regulatory approach to protect human health is needed.

Amphibien sind die weltweit am stärksten gefährdeten Wirbeltiere. Auch in Deutschland steht mehr als die Hälfte der Frösche, Kröten und Molche auf der Roten Liste der gefährdeten Tierarten. Ergebnisse eines Forschungsvorhabens im Auftrag des Umweltbundesamtes (UBA) deuten darauf hin, dass der Einsatz von Pestiziden in der Landwirtschaft mitverantwortlich für den Rückgang der Amphibien ist. In Versuchen führten Pflanzenschutzmittel bei Grasfröschen schon in anwendungsüblichen Mengen zum Tod vieler Tiere. Bei Vögeln und Säugetieren gibt es seit längerer Zeit die Diskussion, ob Pestizide über die Haut aufgenommen werden und wie groß die dadurch bedingte Gefahr ist. Die feuchte Haut von Amphibien absorbiert Stoffe in noch viel größeren Mengen, da sie im direkten Kontakt mit der Umwelt steht. Daher ist die Gefahr der „dermalen Exposition“ hoch. „Amphibien nutzen landwirtschaftliche Flächen als Lebensraum und überqueren sie auf ihren Wanderungen zu den Laichgewässern“, erläutert UBA-Präsident Jochen Flasbarth. „Die Studie zeigt Handlungsbedarf auf. Das Umweltbundesamt hält es für erforderlich, den Schutz der Amphibien in der Produktzulassung, aber auch in der landwirtschaftlichen Praxis stärker zu berücksichtigen.“

“I thought I’d give you a ‘behind-the-scenes’ look into the death of my bees in California. I started out last spring in the Midwest with 3,150 healthy bee colonies; of which 992 still survive, and most of those are very weak. More than 2,150 of my valuable bee colonies are now extinct.” A Midwestern beekeeper friend has earned his living as a migratory bee-farmer for almost 40 years; his son represents the fourth generation of this family to enter the beekeeping business. For most of those decades, the practice of migratory beekeeping was relatively trouble-free; the bees were not harmed by being trucked around America; there was no warning of impending disaster. All of that changed with the coming of the new systemic pesticides, the neonicotinoids. During summer in the Midwest, colonies build-up on pollen from maize, and dandelions while gathering nectar from soybeans, alfalfa, clovers and linden trees. Sadly, the maize and soybeans are seed-treated with systemic neonicotinoid insecticides, which emerge later, in the pollen and nectar, to poison the bees. To make matters worse, later in the season, those same crops are sprayed with additional: fungicides, herbicides and insect-growth-regulators (IGRs). Combined with the systemic neonicotinoids, these react ‘synergistically’, to produce a witches’ brew of poison that is far more toxic than any pesticide on its own.

Kamerlid Esther Ouwehand zal gedupeerden van mestvergisters en lelieakkers in Drenthe donderdag een hart onder de riem steken. In Drenthe worden steeds meer lelies geteeld. Bij deze teelt worden veel giftige bestrijdingsmiddelen en grondontsmettingsmiddelen gebruikt. Mensen die het gif op de planten spuiten, moeten beschermende kleding dragen om hun gezondheid niet in gevaar te brengen. Omwonenden van de akkers leven echter permanent in de gifdampen. Op aandringen van de Partij voor de Dieren voert de Gezondheidsraad momenteel een onderzoek uit naar de effecten daarvan op de gezondheid van de omwonenden. Esther Ouwehand: “De negatieve gevolgen van het landbouwbeleid worden in Drenthe pijnlijk duidelijk. Mensen wonen in de stank van mestvergisters en in de gifdampen van de lelievelden. De gevolgen hiervan voor hun gezondheid en welbevinden lijken er voor lokale overheden niet of nauwelijks toe te doen. Deze mensen zijn de dupe van het CDA-landbouwbeleid van de afgelopen jaren. Het is hoog tijd dat Nederland afscheid neemt van de intensieve landbouw met al zijn schadelijke effecten om mens, dier en milieu. Volksgezondheid en het milieu verdienen bescherming boven de economische belangen van agrariërs.”

Nötig seien zumindest zehn Prozent der landwirtschaftlich genutzten Flächen und der Naturräume für die Artenvielfalt, forderten der stellvertretende Nabu-Landeschef Rainer Hanke und die Thüringer Imkerverbände am Dienstag (12.02.2013) in Weimar. Vor allem Umweltgifte und Pflanzenschutzmittel dezimierten die wichtigen Insekten, erklärte Hanke. Dies habe gravierende Auswirkungen auf das gesamte Ökosystem. So gehe die Zahl der bestäubten Blütenpflanzen seit Jahrzehnten zurück. "Die Insekten bilden die Grundlage der Nahrungsmittelpyramide", betonte Mike Wünscher vom Landesverband der Buckfastimker Thüringen und Sachsen-Anhalt. Inzwischen sei es normal, wenn 10 bis 20 Prozent einer Bienenpopulation den Winter nicht überlebten. Vor 30 Jahren hätte die Sterblichkeit noch bei unter 2 Prozent gelegen, fügte er hinzu. Unterstützung bekamen die Bienenfreunde von der Grünen-Fraktion und der Linkspartei im Landtag. Laut einer EU-Richtlinie müssen derzeit sieben Prozent der landwirtschaftlichen Betriebsflächen für die sogenannte Biodiversität (Artenreichtum, biologische Vielfalt) reserviert werden. Nach Angaben der Thüringer Imkerverbände werden in Thüringen etwa 18.700 Bienenvölker von rund 2350 Imkern betreut. Damit kommt nur etwa ein Volk auf jeden Quadratkilometer des Freistaats. Für eine angemessene Bestäubung werde aber eine vierfache Population benötigt.

Twelve papers in this series were derived from two conference sessions focusing on causality in field studies. Eight of these papers involve case studies examining biological effects of chemical contaminants in field situations. Using a weight-of-evidence approach, these case studies were evaluated against seven proposed criteria for establishing causality. The seven criteria were: strength of association; consistency of association; specificity of association; time order; biological gradient; experimental evidence; and biological plausibility. One of these seven criteria, ‘specificity of association’ was found to be of little utility for establishing causality in these field studies. The case studies are presented in approximate order of increasing levels of biological organization (i.e., going from endpoints at the suborganismal level to endpoints at the population or community level). In case studies examining higher levels of biological organization, it appears that the ‘biological gradient’ criterion was also not useful in establishing causality. These results, together with suggestions from other papers in the series, are used to recommend a set of modified criteria for establishing causality in field studies of the biological effects of chemical contaminants.

Swiss group Syngenta forecast another year of record sales as high crop prices and erratic weather spur farmers to use more of its pesticides, fertilisers and advanced seeds to boost yields. Net profit rose 17 percent to $1.87 billion to beat the average analyst forecast in a Reuters poll. Sales at Syngenta, which competes with DuPont, and Germany's Bayer, rose 7 percent in 2012 to $14.2 billion, falling just short of the average analyst forecast of $14.3 billion. Syngenta, which sells products to kill weeds and bugs as well as genetically-modified seeds, is targeting sales of its top eight crops of $25 billion by 2020. The Basel-based firm announced a dividend of 9.50 Swiss francs per share, up from 8 francs a year ago. A sharp fall in bee populations around the world in recent years has prompted criticism of pesticide use and last week the European Commission said it wanted EU member states to suspend the use of neonicotinoid insecticides. Mack said the decision was "scientifically misguided", but said it would have no material impact on 2013 sales as any restriction would only come into place after the sunflower, oil seed rape and corn is largely sown. Its pesticide, named Cruiser OCR, makes up less than 0.5 percent of group sales, and Chief Executive Mack said Syngenta would try to offset any loss in revenue through other products.

SP-Kamerlid Henk van Gerven stelt voor het concurrentienadeel van landbouwers die schoon voedsel produceren te verminderen. Van Gerven: 'Schoon voedsel is belangrijk voor de volksgezondheid en het milieu, maar helaas is er nog teveel voedsel waar bij de productie onnodig veel bestrijdingsmiddelen worden gebruikt. Boeren die minder bestrijdingsmiddelen gebruiken hebben een concurrentienadeel omdat hun manier van bestrijding arbeidsintensiever is of omdat hun zaaigoed nog duurder is. Dat verschil tussen schone en vieze landbouwproductie kan kleiner worden als de schadelijke effecten van bestrijdingsmiddelen belast worden.' Van Gerven noemt als voorbeeld een uienplant die resistent is tegen meeldauw, waardoor er geen bestrijdingsmiddel op gespoten hoeft te worden. Het zaaigoed van de meeldauwresistente ui is echter duurder en daarom gebruiken nog veel boeren het goedkopere gewone uienzaaigoed plus de bijbehorende spotgoedkope bestrijdingsmiddelen. De boer die schoon wil produceren is daarbij in het nadeel terwijl de waterwinbedrijven met oplopende kosten zitten omdat het grondwater onnodig vervuild wordt.

The pesticide brew in many ponds bordering Midwestern cornfields is not only affecting the sexual development of frogs, but is making them more prone to deadly bacterial meningitis, according to a new study by University of California, Berkeley, scientists. These physiological effects combine with environmental disruptions to make the life of a frog seem like something out of a horror movie and are likely among the factors causing a decline in amphibian populations worldwide, the researchers said. "If you look at one of these frogs, it's probably a hermaphrodite - plus, it metamorphoses late, which means it is subject to its pool drying up before it can become a frog," said lead researcher Tyrone Hayes, professor of integrative biology at UC Berkeley. "It's also smaller, if it metamorphoses at all, which increases the likelihood it will be eaten and decreases its ability to eat. Plus, it's immuno-suppressed, so more prone to die from infection." The stress on the frogs is increasing stress hormone levels, he found, which in turn create holes in the thymus gland that likely cause the impaired immune response. "It's not the pesticides alone or introduced predators or ultraviolet light or global warming that's causing this decline, but the interaction between these on an animal that is pretty sensitive to its environment," said Hayes.