The Global Fool

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Neonicotinoid Pesticides: Bad for Bees, Bad for Many Other Species
May06

Neonicotinoid Pesticides: Bad for Bees, Bad for Many Other Species

By Roberta Attanasio Do neonicotinoid pesticides harm bees? According to scientific evidence, the answer is “yes”. Indeed, scientific evidence for the toxic effects of neonicotinoid pesticides on bees is accumulating at an increasing pace. And, on the basis of scientific evidence, the European Commission banned in 2013 the use of three neonicotinoids — clothianidin, imidacloprid and thiamethoxam — on flowering plants. The ban was motivated by findings from the European Food Safety Authority (EFSA); these findings were based on the evaluation of the scientific studies available at the time. Now, a report from the European Academies Science Advisory Council (EASAC) emphasizes that bees are not the only species affected by the use of these pesticides. The report is based on the findings of an international group of independent scientists with expertise ranging from pollination biology through systems ecology to toxicology. According to the report, there is more and more scientific evidence that widespread use of neonicotinoids has severe effects on species that are important for pollination, natural pest control, and soil productivity. For example, predatory insects such as parasitic wasps and ladybugs that aid in pest control, and earthworms that improve soil productivity, are all harmed. In addition, neonicotinoid use has a negative impact on biodiversity. Neonicotinoids are neurotoxic (poisonous to nerves or nervous tissue of insects and other organisms), and act systemically in the plants — their solubility in water allows them to be absorbed and spread via the plant’s vascular system to all of its tissues. They reach leaves, flowers, roots and stems, even pollen and nectar, and become toxic not only to sap-sucking pests such as aphids or mealybugs, but also to any other species that harvest the different parts of the plant. In addition, exposure is possible across trophic levels, as for example in the case of bees foraging on honey dew, predators exposed through ingesting prey, or soil organisms decomposing contaminated organic matter. There is also evidence for sub-lethal effects of very low levels of neonicotinoids, over extended periods of time, on non-target beneficial organisms. Repeated sub-lethal doses may eventually become deadly once a certain threshold is passed. The EASAC report acknowledges that use of all pesticides is based on the balance between the desired effect on food production and the inevitable risk of collateral damage to non-target species and the environment. However, for neonicotinoids, scientific evidence accumulated over the last two years suggests that, rather than balance, there in imbalance —  the risk of collateral damage is too high when compared to the benefits. Peter Neumann, EASAC’s Chair of the Working Group, wrote in an article published in the journal Nature that the...

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Clean Air: The Effects of U.S. Power Plant Carbon Standards on Human Health
May04

Clean Air: The Effects of U.S. Power Plant Carbon Standards on Human Health

By Roberta Attanasio A little more than a year ago, the World Health Organization (WHO) reported that in 2012 around 7 million people died — accounting for one in eight of total global deaths — as a result of exposure to air pollution. These estimates more than doubled the previous ones, and confirmed that air pollution is now the world’s largest single environmental health risk. The WHO concluded that reducing air pollution globally could save millions of lives. But, what policy changes would be most effective at saving lives? The answer comes from a new study published in the journal Nature Climate Change (May 4, 2015.) The study, (US power plant carbon standards and clean air and health co-benefits), was based on data from the Census Bureau as well as detailed maps of the more than 2,400 fossil-fuel-fired power plants operating across the U.S. It outlines how changes in carbon dioxide emissions could lead to considerable health benefits for the U.S population. According to the WHO, the diseases caused by air pollution include ischemic heart disease (40%), stroke (40%), chronic obstructive pulmonary disease (11%), lung cancer (6%), and acute lower respiratory infections in children (3%). For the new study, the researchers analyzed three possible policy options for power plant carbon standards. The policy option leading to the biggest health benefits was the one that included changes proposed by the U.S. Environmental Protection Agency (EPA) on June 2, 2014, in the Clean Power Plan. Modeling analysis indicated that this option could prevent an expected 3,500 premature deaths in the U.S. every year, and avert more than a thousand heart attacks and hospitalizations annually from air pollution-related illness. Thus, according to the study, the formula presented in the draft Clean Power Plan is on the right track to provide large health benefits, and these health benefits depend entirely on critical policy choices that will be made by the EPA in the final Clean Power Plan expected in July. The Plan is the nation’s first attempt to establish standards for carbon dioxide emissions from power plants. It is also viewed as an important signal of U.S. leadership in the run-up to international climate negotiations in Paris in December. Jonathan Buonocore, one of the researchers involved in the study, said in a press release: “If EPA sets strong carbon standards, we can expect large public health benefits from cleaner air almost immediately after the standards are implemented.” Power plants are the nation’s largest source of carbon dioxide emissions that contribute to climate change. However, they release not only carbon dioxide, but also other pollutants such as sulfur dioxide, nitrogen oxides and particulate matter — precursors to smog and...

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Global Threats: Contamination of Surface Waters by Agricultural Insecticides
Apr26

Global Threats: Contamination of Surface Waters by Agricultural Insecticides

By Roberta Attanasio The use of agricultural insecticides — toxic substances developed to target and kill insects that damage crops — has sparked controversy since the dawn of the “chemical age”, which started in the 1950s. The benefits of agricultural insecticides — for example, increased food production — are undeniable. Unfortunately, along with benefits, there are considerable unwanted effects. Ideally, insecticides must be lethal to the target insects, but not to non-target species. However, these toxic substances do not target only insects — they target many more organisms, including man. Thus, the toxic brew of agricultural insecticides threatens the ecological integrity of aquatic and terrestrial ecosystems. Indeed, agricultural systems play a significant role in global environmental degradation — among other harmful effects, they drive the loss of aquatic biodiversity. In 2013, a team of researchers from German and Australian institutions showed that the loss of aquatic biodiversity in regions of Germany, France, and Australia, is primarily due to the disappearance of several groups of species — stoneflies, mayflies, caddisflies, and dragonflies — which are especially susceptible to insecticides. These insects are important members of the food chain right up to fish and birds. Despite these worrisome results, the degree of insecticide contamination worldwide was unknown until two weeks ago, when results from a new study (Agricultural insecticides threaten surface waters at the global scale) showed that surface water pollution resulting from the current use of agricultural insecticides constitutes an excessive threat to aquatic biodiversity. For the new study, researchers at the Institute for Environmental Science of the University of Koblenz-Landau evaluated, for the first time, comprehensive global insecticide contamination data for agricultural surface waters. They examined 838 studies conducted between 1962 and 2012 and covering 2,500 aquatic sites in 73 countries, using the legally-accepted regulatory threshold levels (RTLs) as defined during the official pesticide authorization procedures. The researchers found that insecticide contamination occurs rarely in the aquatic environment — only an estimated 2.6% of the samples contained measurable levels of insecticides. However, for the sites containing insecticides, the results were alarming — more than 40% of the water-phase samples, and more than 80% of sediment samples in which insecticides were detected, yielded concentrations that exceeded the respective RTLs. They concluded that insecticides pose substantial threats to the biodiversity of global agricultural surface waters and that the current regulatory risk assessment schemes and pesticide authorization procedures fail to protect the aquatic environment. Ralf Schulz, one of the researchers, said in a press release: “Potential reasons for these findings are failures of current risk assessment procedures, or the non-adherence of farmers to pesticide application prescriptions.” It is likely that the global picture emerging from the...

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Prenatal Exposure to Air Pollutants: Links to Attention Deficit Hyperactivity Disorder
Apr11

Prenatal Exposure to Air Pollutants: Links to Attention Deficit Hyperactivity Disorder

By Roberta Attanasio PHAs — short for polycyclic aromatic hydrocarbons — are bad actors: they’re toxic, ubiquitous pollutants that readily cross the placenta, causing damage to the fetal brain. Now, results from a new study show that PHA-induced fetal brain damage may lead to severe behavioral problems during early childhood, including aggression and attention deficit hyperactivity disorder (ADHD). The deleterious effects of air pollution — greater risk of stroke, heart attacks and cognitive deterioration — are widely recognized. However, the new study assessed prenatal exposure and identified specific physical damage in the brain. The researchers used magnetic resonance imaging to measure the brains of 40 children from a cohort consisting of more than 600 mother-baby pairs. The mothers were either Latina (Dominican) or African American nonsmoking women from minority communities in New York City, aged 18 to 35 years. During the third trimester of pregnancy, the women carried personal backpack monitors that measured exposure to eight common PAHs over 48 hours. Such exposure occurred by breathing contaminated air. PHAs — common components of air pollution — are often found together in groups of two or more and persist in the environment for long periods of time. They’re generated by motor vehicles, waste incineration, wildfires and agricultural burning, and oil and coal burning for heat and electricity. Cooking (especially charred foods), tobacco smoke, and space heaters are indoor sources of PHAs. Low-income, urban, and minority communities are disproportionately exposed to these air pollutants. The researchers had previously demonstrated that exposure of the pregnant women from the same cohort to airborne PAHs was associated with multiple neuro-developmental disturbances. Results form the new study indicate that such disturbances have a biological root in the altered architecture of the brain. Specifically, PHA exposure was linked to reductions of the white matter surface in later childhood. These reductions were confined almost exclusively to the left hemisphere of the brain, and involved almost its entire surface. The researchers don’t know why the left side seemed to be affected more, but they suspect the compounds interfere with an early biochemical process that helps the fetal brain divide into slightly asymmetrical hemispheres. Results from the study also show that postnatal PAH exposure correlates with white matter surface measures in other regions of the brain, the dorsal prefrontal regions. Thus, the children involved in the study were exposed to “a double hit”, first as developing fetuses, and then at an early age. Indeed, Bradley Peterson, lead author of the study, told the Los Angeles Times: “It’s a double hit. They have the abnormality from prenatal life throughout the left hemisphere and then on top of that they have...

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Food Additives, Microbiota, and Inflammation
Mar27

Food Additives, Microbiota, and Inflammation

By Roberta Attanasio “For centuries, additives have served useful functions in a variety of foods. Our ancestors used salt to preserve meats and fish, added herbs and spices to improve the flavor of foods, preserved fruit with sugar, and pickled cucumbers in a vinegar solution. Today, consumers demand and enjoy a food supply that is flavorful, nutritious, safe, convenient, colorful and affordable. Food additives and advances in technology help make that possible.” But, are food additives safe? Results from a recent study show that some food additives known as emulsifiers can alter the composition and location of the gut microbiota — the diverse population of 100 trillion bacteria that inhabit the intestinal tract — thus inducing intestinal inflammation. This inflammation, in turn, promotes the development of inflammatory bowel disease (Crohn’s disease and ulcerative colitis) and metabolic syndrome — disorders that are often severe and debilitating and afflict millions of people. The ancient Greeks used the emulsifying power of beeswax in cosmetic products. Egg yolk was probably the first emulsifier ever used in food production back in the early 19th century. Emulsifiers are now added to bread, chocolate, ice cream, margarine, processed meat, and more. But why? Add oil to water and the two liquids will never mix. At least not until an emulsifier is added. Emulsifiers are molecules with one water-loving (hydrophilic) and one oil-loving (hydrophobic) end. They make it possible for water and oil to become finely dispersed in each other, creating a stable, homogenous, smooth emulsion. The study results show that, in a mouse model, two common emulsifiers — caboxymethylcellulose (CMC) and polysorbate-80 (P80) — not only change the composition of the gut microbiota, they also make the gut more porous. The altered microbiota has enhanced capacity to digest and infiltrate the dense mucus layer that lines the intestine — bacteria reach immune cells, thus inducing activation of inflammatory pathways and the development of severe inflammation. Such changes in bacteria trigger chronic colitis in mice genetically prone to this disorder, due to abnormal immune systems. In contrast, in mice with normal immune systems, emulsifiers induce low-grade or mild intestinal inflammation and metabolic syndrome, characterized by increased levels of food consumption, obesity, hyperglycemia and insulin resistance. Fergus Shanahan (University College Cork), who was not involved in the study, told Ed Yong: “This work cannot be ignored.” He doubted that most people would be significantly affected by occasionally eating foods with emulsifiers — but risk might change for those who have a genetic predisposition to inflammatory bowel disease, or who eat lots of processed foods. Andrew Gewirtz, senior author of the study, said in a press release: “We do...

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