The Global Fool

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Air Pollution: The Most Widespread Environmental Carcinogen
Oct19

Air Pollution: The Most Widespread Environmental Carcinogen

By Roberta Attanasio Exposure to outdoor air pollution causes lung cancer in humans – this is the conclusion drawn by leading experts after thoroughly reviewing the latest available scientific literature.  The same experts evaluated particulate matter separately and reached a similar conclusion. Therefore, particulate matter is now classified as carcinogenic to humans. These conclusions apply to all regions of the world as they are based on findings from large epidemiologic studies that include millions of people living in different continents. The experts were convened by the IARC Monographs Programme. IARC (International Agency for Research on Cancer) is the specialized cancer agency of the World Health Organization (WHO). The IARC Monographs identify environmental factors that can increase the risk of human cancer. These factors include chemicals, complex mixtures, occupational exposures, physical agents, biological agents, and lifestyle factors. National health agencies can use such information as scientific support for their actions to prevent exposure to potential carcinogens. The IARC Monographs Programme announced the findings related to air pollution, particulate matter and human cancer on October 17, 2013. Both air pollution and particulate matter are now considered Group 1 carcinogens. The Group 1 category is used when there is sufficient evidence of carcinogenicity in humans. Dr. Kurt Straif, Head of the IARC Monographs Section, said “The air we breathe has become polluted with a mixture of cancer-causing substances. We now know that outdoor air pollution is not only a major risk to health in general, but also a leading environmental cause of cancer deaths.” The major sources of air pollution across the globe are emissions from motor vehicles, industrial processes, power generation and household combustion of solid fuel. The precise chemical and physical features of air pollution, which comprises a myriad of individual chemical constituents, vary around the world due to differences in the sources of pollution, climate, and meteorology, but the mixtures of ambient air pollution invariably contain specific chemicals known to be carcinogenic to humans. The disease burden due to air pollution is substantial, with millions of death caused by cardiovascular disease. According to “Air Pollution and Cancer”, IARC Scientific Publication No. 161, the most recent data indicate that in 2010, air pollution caused 223,000 deaths from lung cancer worldwide. Dr. Christopher Wild, IARC Director, said “Classifying outdoor air pollution as carcinogenic to humans is an important step. There are effective ways to reduce air pollution and, given the scale of the exposure affecting people worldwide, this report should send a strong signal to the international community to take action without further delay.” Don’t forget: You can help keep the air cleaner — every day!...

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Fine Particulate Matter: The Global Toll
Oct18

Fine Particulate Matter: The Global Toll

By The Editors Particulate matter, also known as particle pollution or PM, is a complex mixture of very tiny solid and liquid particles made up of several components, including acids (such as nitrates and sulfates), organic chemicals, metals, and soil or dust particles. Fine particles (PM2.5) are found in smoke and haze and are 2.5 micrometers in diameter and smaller. Sources of fine particles include all types of combustion — motor vehicles, power plants, residential wood burning, forest fires, agricultural burning, and some industrial processes. Fine particles cause serious health problems such as heart disease, lung cancer and asthma attacks as they can get deep into the lungs — some may even get into the bloodstream. Results from a study published in July 2013 in the journal Environmental Research Letters and entitled “”Global premature mortality due to anthropogenic outdoor air pollution and the contribution of past climate change” indicate that 2.1 million deaths occur worldwide each year as a direct result of exposure to fine particles. Results from the study also indicate that climate change has a minimal effect on current deaths related to air pollution. Co-author of the study, Jason West, from the University of North Carolina, said: “Our estimates make outdoor air pollution among the most important environmental risk factors for health. Many of these deaths are estimated to occur in East Asia and South Asia, where population is high and air pollution is severe.”   The map shown here is from the NASA Earth Observatory. It is based on data provided by West and depicts the model estimate of the average number of deaths per 1,000 square kilometers (386 square miles) per year due to air pollution. In their study, West and collaborators used estimate mortality for changes in air pollution relative to the the difference in pollution levels between 1850 (modeled preindustrial conditions) and 2000 as a measure of human-caused air pollution. Dark brown areas have more premature deaths than light brown areas. Blue areas have experienced an improvement in air quality relative to 1850 and a decline in premature deaths. Fine particulate matter takes an especially large toll in eastern China, northern India, and Europe — all areas where urbanization has added considerable quantities of PM2.5 to the atmosphere since the start of the Industrial Revolution. A few areas — such as the southeastern United States — saw PM2.5 concentrations decline relative to pre-industrial levels (shown in blue). In the southeastern United States, the decrease in PM2.5 is likely related to a decline in local biomass burning that has occurred over the last 160 years. Of the estimated 2.1 million deaths occurring  worldwide each year as a direct result of exposure to fine particles, 93% are caused...

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Asthma in Children: Effects of Exposure to Diesel Exhaust Particles
Oct12

Asthma in Children: Effects of Exposure to Diesel Exhaust Particles

By The Editors Diesel exhaust particles are one of the major components of air pollution. These particles are suspended in the air, and are microscopic — less than one-fifth the thickness of a human hair. As we breathe, they are drawn deep into the lungs. Because diesel-powered engines are everywhere, it is almost impossible to avoid them. People that live and work in urban and industrial areas are more likely to be exposed. Combined results from many epidemiological, clinical, and toxicological studies show that diesel exhaust particles are associated with respiratory disorders, as for example severe asthma. It is not surprising that children are especially susceptible to the effects of these particles. Results form a recenty study entitled “Diesel exhaust particle induction of IL-17A contributes to severe asthma” and published onine (September 23, 2013) in the Journal of Allergy and Clinical Immunology,  show that exposure to diesel exhaust particles from traffic pollution leads to increased asthma severity in children. The study was conducted by researchers at Cincinnati Children’s Hospital Medical Center. and provides insight into the mechanisms responsible for the development of severe asthma in children exposed to high levels of diesel exhaust particles — these mechanisms involve expansion of a type of white blood cells called T helper 17 cells and increased production by these cells of a protein, IL-17A. This protein is known to be associated with several chronic inflammatory diseases, including rheumatoid arthritis, psoriasis and multiple sclerosis. The researchers studied 235 children and teens with asthma by estimating their diesel exposure attributable to traffic based on where they lived. The researchers also studied mice exposed to diesel particles and dust mites, a common household allergen. In children with asthma, diesel exposure was associated with more frequent asthma symptoms and increased IL-17A blood levels. In mice, exposure to diesel and dust mites resulted in more severe asthma when compared to dust mite exposure alone. Neutralization of IL-17A in mice resulted in alleviation of airway inflammation induced by diesel exposure. Gurjit Khurana Hershey, MD, PhD, director of asthma research at Cincinnati Children’s and senior author of the study says that neutralization of IL-17A “may be a useful potential therapeutic strategy to counteract the asthma-promoting effects of traffic-related air pollution, especially in highly exposed, severe allergic...

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Doing Your Bit: Ten Simple Ways to Help Reduce Air Pollution
Aug11

Doing Your Bit: Ten Simple Ways to Help Reduce Air Pollution

By The Editors Every day, we can choose to do things that help to reduce air pollution. And if we are aware of what we do, we can do even more. Below are a few ideas to make a difference – Ten simple ways to help reduce air pollution.   1. Conserve energy – turn off appliances, computers and lights when you leave the room. Connect your outdoor lights to a timer or use solar lighting.     2. Dress for the weather and adjust layers before adjusting the thermostat. 3. Seal containers of household cleaners, workshop chemicals and solvents, as well as garden chemicals to prevent volatile organic compounds (VOC) from evaporating into the air. Use water-based or solvent free paints whenever possible and buy products that say “low VOC”. 4. Recycle paper, plastic, metals and organic materials. 5. Avoid using chemical pesticides or fertilizers in your yard and garden. Compost your yard waste. Do not use blowers – use a rake, instead. 6. Keep your vehicle well maintained. Replace oil and air filters regularly, and keep your tires properly inflated and aligned. 7. In the summertime, fill the gas tank during cooler evening hours to cut down on evaporation. Avoid spilling gas and don’t “top off” the tank. Replace the gas tank cap tightly. 8. Don’t buy more car than you need. Four-wheel drive, all-wheel drive, engine size, vehicle weight, and tire size all affect the amount of fuel your vehicle uses. 9. Ask your employer to consider flexible work schedules or telecommuting. 10. Advocate for emission reductions from power plants and more stringent national vehicle emission...

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What is Carbon Farming?
Aug08

What is Carbon Farming?

By Roberta Attanasio Greenhouse gases (carbon dioxide, methane, nitrous oxide, fluorinated gases, and ozone) work like the glass walls of a greenhouse and are responsible for the greenhouse effect. What is the greenhouse effect? It’s a process in which greenhouse gases let the radiation from the sun onto the Earth’s surface. At the same time, they trap the heat that reflects back up into the atmosphere. The greenhouse effect keeps our planet at an average 59 degrees Fahrenheit (15 degrees Celsius).  However, if the greenhouse effect is too strong, our planet gets warmer and warmer. This is what is happening now — the greenhouse effect is becoming stronger because of increased release of greenhouse gases in the atmosphere. The result of a stronger greenhouse effect is climate change. Carbon dioxide (CO2) is the primary greenhouse gas emitted through human activities. CO2 enters the atmosphere through burning fossil fuels (coal, natural gas and oil), solid waste, trees and wood products, and also as a result of certain chemical reactions (e.g., manufacture of cement). Carbon dioxide is removed from the atmosphere when it is absorbed by plants as part of the biological carbon cycle. Using energy from the sun, plants transform carbon dioxide and water into glucose and oxygen through the process of photosynthesis. CO2 is said to be removed, captured or sequestered (in such a context, these three words have the same meaning). To mitigate climate change, a group of German scientists has now come up with an environmentally friendly method to capture CO2 — in other words, a method to remove CO2 from the atmosphere. The method, dubbed carbon farming, consists in planting trees in arid regions to capture CO2. The team of investigators, in a paper published in the scientific journal Earth System Dynamics on July 31, 2013, shows that Jatropha curcas does a great job at sequestering CO2 from the atmosphere.  Jatropha curcas is a small tree very resistant to aridity. Therefore, it can be planted in hot and dry land in soil unsuitable for food production. Because the plant needs water to grow, coastal areas where desalinated seawater can be made available are ideal. The new Earth System Dynamics study shows that one hectare of Jatropha curcas could capture up to 25 tonnes of atmospheric carbon dioxide per year, over a 20 year period. A plantation taking up only about 3% of the Arabian Desert, for example, could absorb in a couple of decades all the CO2 produced by motor vehicles in Germany over the same period. With about one billion hectares suitable for carbon farming, the method could sequester a significant portion of the CO2 added to the atmosphere since the industrial revolution. The main limitations to implementing this method are lack...

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