Insecticides

Millions of children in the U.S. are being exposed to insecticides that are currently used daily in homes around the country. According to a recent study published by Canadian researchers, the exposure to pyrethoid pesticides found in thousands of home products, including cockroach sprays and flea controls, was found to be associated with neurobehavioral deficits in children. In the most recent study, constructing data from children ages six to 11, the Canadian Health Measures Survey researchers analyzed the organophosphate and pyrethoid metabolites in their urine. The researchers used logistic regressions to estimate odd ratios for high scores on the Strengths and Difficulties Questionnaire, which may indicate the presence of certain behavioral problems. During the study, each parent was asked a series of three questions regarding their use of indoor pesticides, pyrethoid pesticides and outdoor pesticides during that month. The results of the study showed a strong correlation between the use of pesticides and high scores on the questionnaire.

Zum Schutz der Bienen soll der Bund die Risiken durch Pestizide bis 2023 reduzieren. Dies fordert nach dem Nationalrat auch die Wissenschaftskommission (WBK) des Ständerates. Die Kommission empfiehlt dem Ständerat einstimmig, eine entsprechende Motion anzunehmen, wie die Parlamentsdienste am Dienstag mitteilten. Der Vorstoss verlangt ein Massnahmenpaket zur nachhaltigen Nutzung von Pflanzenschutzmitteln. Eine Petition zur Verbesserung der Situation der Honigbienen hat die Kommission abgelehnt. Sie sei überzeugt, dass die Situation der Honigbienen dank der Forschung zu den Auswirkungen von Pflanzenschutzmitteln verbessert werden könne, hält sie fest.National- und Ständerat haben den Bundesrat vor kurzem beauftragt, bis Ende 2015 die Ursachen des Bienensterbens wissenschaftlich untersuchen zu lassen und die nötigen Schutzmassnahmen zu ergreifen.

New York City residents are more highly exposed to two types of widely used pesticides than the U.S. average, according to a new study. The findings “underscore the importance of considering pest and pesticide burdens in cities when formulating pesticide use regulations,” the researchers from the city's Department of Health and Mental Hygiene wrote in the journal Environmental Health Perspectives. Organophosphate metabolites were measured in the urine of 882 New Yorkers, while 1,452 residents were tested for pyrethroid metabolites. Some organophosphates have been banned in the United States in recent years, although many are still heavily used in agriculture. Pyrethroids are used indoors and outdoors in sprays and bug bombs to kill fleas, mosquitoes and other pests. Among New Yorkers who were 20 to 59 years old in 2004, the highest exposed group had between two and six times more organophosphates in their urine than the highest exposed group in a national study. They also had between 1.7 and 2.4 times more pyrethroids than the nationwide group. In previous studies in New York City and in a California farm area, prenatal exposure to organophosphates has been associated with reduced mental skills in children.

In the closing years of the nineteenth century German scientists sought for the ‘silver bullet’ – an elixir to relieve all aches and pains. Their discovery of an opium derivative appeared to be just that – a ‘heroic’ medicine. So they christen it ‘heroin.’ Half-a-century later Germany researchers were once again attempting to dscover a substitute for the nicotine insecticides then in short supply. In 1938 four scientists at IG Farben in Wuppertal-Elberfeld created just such a stronger pesticide. It was named in honour of its discoverers Schrader, Ambros, Rüdiger and Van der Linde: sarin. Sixty-five years later, sarin was used as a chemical weapon by the Bashar al-Assad’s Syrian regime to kill more than 1,400 people on 21 August, incurring the world’s wrath. Sarin is an organophosphate, a group of highly successful and widely used chemicals used for control of a broad spectrum of crop insect and arachnid pests. They include such popular preparations as malathion, diazinon and chlorpyrifos (Dursban®), dimethoate (Cygon®) and dichlorvos (Vapona®) all widely distributed for home use at least until recently. Most are still available for agricultural and forestry use, accompanied by an alarming number of other organophosphates, many of whose tongue-twisting names conceal their lethal nature.

In less than 20 years, neonicotinoids have become the most widely used class of insecticides with a global market share of more than 25%. For pollinators, this has transformed the agrochemical landscape. These chemicals mimic the acetylcholine neurotransmitter and are highly neurotoxic to insects. Their systemic mode of action inside plants means phloemic and xylemic transport that results in translocation to pollen and nectar. Their wide application, persistence in soil and water and potential for uptake by succeeding crops and wild plants make neonicotinoids bioavailable to pollinators at sublethal concentrations for most of the year. This results in the frequent presence of neonicotinoids in honeybee hives. At field realistic doses, neonicotinoids cause a wide range of adverse sublethal effects in honeybee and bumblebee colonies, affecting colony performance through impairment of foraging success, brood and larval development, memory and learning, damage to the central nervous system, susceptibility to diseases, hive hygiene etc. Neonicotinoids exhibit a toxicity that can be amplified by various other agrochemicals and they synergistically reinforce infectious agents such as Nosema ceranae which together can produce colony collapse. The limited available data suggest that they are likely to exhibit similar toxicity to virtually all other wild insect pollinators. The worldwide production of neonicotinoids is still increasing. Therefore a transition to pollinator-friendly alternatives to neonicotinoids is urgently needed for the sake of the sustainability of pollinator ecosystem services.

Sie kommen mit körperlichen Defekten zur Welt oder erkranken überdurchschnittlich oft an Krebs: In Argentinien leiden Menschen unter dem massiven und illegalen Einsatz von Pestiziden. Das Gift trägt wesentlich zum wirtschaftlichen Erfolg des Landes durch Soja-Produktion bei. Mithilfe moderner Biotechnologie ist Argentinien zum weltweit drittgrößten Soja-Hersteller aufgestiegen. Der massive Einsatz chemischer Mittel hat an diesem Erfolg großen Anteil. Doch die giftigen Stoffe werden teilweise direkt neben Wohnhäusern und Schulen ausgebracht und kontaminieren das Trinkwasser. Wissenschaftler und Ärzte warnen vor der unkontrollierten Nutzung der Chemikalien: Sie glauben, dass aus diesem Grund immer mehr Menschen in Argentinien erkranken.

New Zealand is facing an invasion of Argentine ants (Linepithema humile), which compete with native southern ants (Monomorium antarcticum). The insects often meet in urban or agricultural areas, where neonicotinoids are in use. So ecologist Rafael Barbieri, a graduate student in the lab of Philip Lester at Victoria University of Wellington, wondered whether the behavioural changes that have been associated with sublethal neonicotinoid exposure in other insects affect how the two species interact. “Any changes in behaviour could potentially affect the structure of the entire community,” he says. As the team describes in Proceedings of the Royal Society B1, Barbieri exposed the ants to extremely low doses of a common neonicotinoid and examined how the insecticide affected each species’ behaviour. He did not observe an effect on the foraging behaviour or survivability of either species in isolation, although they did cut the brood size of the invasive Argentine ant in half. But it was when the two species met that the real effects were seen. When the southern ant was exposed to the potent neurotoxins, it became much less aggressive towards the invader. This increased the survival odds of the Argentine ant, and could help it to spread. However, when invasive ants were exposed to the insecticides, they became much more aggressive towards unexposed Southern ants — so aggressive, in fact, that they risked their own lives to attack. As a result, unexposed natives were able to completely eradicate their exposed rivals.

The Associated Press’ report described pesticide use near heavily populated areas, children being regularly exposed to harmful agrochemicals, the contamination of water supplies, and workers who were not properly trained to handle such pesticides. The AP report focused on regions in Argentina that produce soybeans, cotton and corn. According to the news agency, Argentina adopted the use of genetically modified organisms, GMOs, as well as agrochemicals from Monsanto Co., in 1996 and all of the country’s soy crops, with corn and cotton just behind, are genetically modified. Despite the claims from Monsanto that pesticide use would decrease with GMO crops, the new report indicates instead a dramatic increase, from nine million gallons used in 1990 to 84 million gallons in 2013. That number, per square acre, is more than double the pesticide use in the United States, reports AP.