Insecticides

Research is urgently needed to evaluate the risks and benefits of nano-pesticides to human and environmental health. Melanie Kah and Thilo Hofmann from the Department of Environmental Geosciences of the University of Vienna recently performed an extensive analysis of this emerging field of research. The results were published June 6th in the internationally recognised journal "Critical Reviews in Environmental Science and Technology". The study presents the current scientific state of art on nano-pesticides and identifies direction priorities for future research.

Pesticides associated to genetically modified foods (PAGMF), are engineered to tolerate herbicides such as
glyphosate (GLYP) and gluphosinate (GLUF) or insecticides such as the bacterial toxin bacillus thuringiensis (Bt). The aim of this study was to evaluate the correlation between maternal and fetal exposure, and to determine exposure levels of GLYP and its metabolite aminomethylphosphoric acid (AMPA), GLUF and its metabolite 3-methylphosphinicopropionic acid (3-MPPA) and Cry1Ab protein (a Bt toxin) in Eastern Townships of Quebec, Canada. Blood of thirty pregnant women (PW) and thirty-nine nonpregnant women (NPW) were studied. Serum GLYP and GLUF were detected in NPW and not detected in PW. Serum 3-MPPA and CryAb1 toxin were detected in PW, their fetuses and NPW.This is the first study to reveal the presence of circulating PAGMF in women with and without pregnancy.

Neonicotinoids aren't just used in agriculture -- unbeknownst to consumers, many “bee friendly” garden plants sold at home garden centers have been pre-treated with these bee killing pesticides which can contaminate their gardens and keep harming bees and other pollinators for months to years. A new, first-of-its-kind pilot study by Friends of the Earth-US and Pesticide Research Institute has found 54% of common garden plants purchased at top retailers including Lowes and Home Depot contained neonicotinoid pesticides, which studies show can harm or kill bees and other pollinators, with no warning to consumers.

Among the various insecticides tested on the grubs of lady bird beetle, Cryptolaemus montruzeiri, buprofezein, azadirachtin and dichlorvas were found to be the safest causing minimum per cent mortality of 33.33, 34.44 and 48.89 per cent respectively. However, highest mortalities of grubs were recorded in imidacloprid, carbaryl and acetamiprid recording 96.67, 92.22, 91.11 per cent mortality of grubs respectively. Buprofezin 25 EC @ 0.01% and azadirachtin 0.03% EC were found safe for adults recording 10.00 and 13.33 per cent mortality, respectively while highest adult mortality was recorded in carbaryl (97.38%) followed by acetamiprid (93.33%) and imidacloprid (92.22%).

Over recent decades, numerous species of bats have been declining, but the causes are not well understood. One of the causes often mentioned is that of environmental toxicants. Feeding on insects makes insectivorous bats more likely to be exposed to insecticides. We sent nine bats (5 Indiana myotis, Myotis sodalis, and 4 northern myotis, Myotis septentrionalis) through U.S. Fish & Wildlife Service (USF&W) sources to be tested for toxicants. Three of these proved to have organophosphate (OP) insecticide residues: chlorpyrifos (0.18 ug/g), diazinon (0.034 ug/g), and methyl parathion (0.015 ug/g). Chlorpyrifos was also detected in all six dead Indiana myotis found during the USF&W Service biennial mid-winter hibernacula surveys in Ray's and Wyandotte Caves, both important Indiana myotis hibernacula. Chlorpyrifos or dichlorvos (another OP) was found in Indiana myotis guano from all four caves sampled (Wyandotte, Coon, Grotto and Ray's). These data are particularly surprising since OP insecticides are thought to have little bioaccumulation in living tissues or in food chains. Their presence in a tissue sample is indicative of exposure shortly before death. Even though exposure to low doses might not be the primary cause of mortality, such exposure could impair echolocation, coordination and response time which, in turn, could lead to significant injuries and death of bats in the field. Presence of OPs in bat guano from caves may suggest insecticide application near these hibernacula and constitutes clear evidence of oral exposure through persistence of toxicants in water or through the food chain.

In eastern Nebraska, we typically see just one species of hummingbird, the ruby-throated hummingbird (Archilochus colubris). Hummingbirds feed on nectar from flowers and tree sap, and on small insects and spiders. While many people attract hummingbirds with feeders, it is better to draw them by planting flowers rich in nectar, which provide better nutrition. Flowers also draw spiders and aphids that hummingbirds use as a protein source. Feeders may be useful in supplementing other sources of nectar and insects (and, of course, to get them closer to your window). Or, better yet, put container pots of pentas, nasturtium or fuschia near the house to attract the hummingbirds and provide a source of natural nectar as well as insects. Because hummingbirds eat gnats and aphids, try to avoid pesticide use where they might be feeding. Another reason to limit pesticides is the potential harm to butterflies. Insecticides kill butterflies as well as other beneficial insects.

Assessment of whether pesticide exposure is associated with neurodevelopmental outcomes in children can best be addressed with a systematic review of both the human and animal peer-reviewed literature. This review analyzed epidemiologic studies testing the hypothesis that exposure to pesticides during pregnancy and/or early childhood is associated with neurodevelopmental outcomes in children. Studies that directly queried pesticide exposure (e.g., via questionnaire or interview) or measured pesticide or metabolite levels in biological specimens from study participants (e.g., blood, urine, etc.) or their immediate environment (e.g., personal air monitoring, home dust samples, etc.) were eligible for inclusion. Consistency, strength of association, and dose response were key elements of the framework utilized for evaluating epidemiologic studies. As a whole, the epidemiologic studies did not strongly implicate any particular pesticide as being causally related to adverse neurodevelopmental outcomes in infants and children. A few associations were unique for a health outcome and specific pesticide, and alternative hypotheses could not be ruled out. Our survey of the in vivo peer-reviewed published mammalian literature focused on effects of the specific active ingredient of pesticides on functional neurodevelopmental endpoints (i.e., behavior, neuropharmacology and neuropathology). In most cases, effects were noted at dose levels within the same order of magnitude or higher compared to the point of departure used for chronic risk assessments in the United States. Thus, although the published animal studies may have characterized potential neurodevelopmental outcomes using endpoints not required by guideline studies, the effects were generally observed at or above effect levels measured in repeated-dose toxicology studies submitted to the U.S. Environmental Protection Agency (EPA). Suggestions for improved exposure assessment in epidemiology studies and more effective and tiered approaches in animal testing are discussed.

Igel (Erinaceus europaeus) sind dämmerungs- und nachtaktive insektenfressende Winterschläfer. Die Nahrung besteht aus Regenwürmern, Schnecken, Raupen, Käfern oder auch Eiern und Jungvögeln von kleinen bodenbrütenden Arten. Aus ihren ursprünglichen Lebensräumen wurden sie verdrängt. Wegen der Verarmung der Landschaft durch oft intensive Land- und Forstwirtschaft (Düngung, Pestizide, Beseitigung von Kleinstrukturen wie Hecken) nehmen Igel Gärten und Parks gerne als Rückzugsgebiet an. Leider sind sie auch hier zahlreichen Gefahren ausgesetzt: Rasenmäher, Kunstdünger, Einsatz von Pestiziden (Entzug der Nahrungsgrundlage) sowie Aufräumwut gefährden den stachligen, aber nützlichen Gesellen. Von Oktober bis Mai hält der Igel Winterschlaf in einem Nest im Kompost, Heuhaufen oder unter Holzstapeln. Während des Winterschlafes zehrt er von seinen angefressenen Fettpolstern. Sinkt sein Gewicht unter 500g in dieser Zeit, verhungert der Igel.