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Air, Water, and Soil Pollution. A meta-study conducted in 2007 by David Pimentel at Cornell University suggests that as many as 40% of all deaths worldwide are linked to soil, water, and air pollution. Air pollution from smoke and various chemicals kills 3 million people a year worldwide.
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Air, Water, and Soil Pollution A meta-study conducted in 2007 by David Pimentel at Cornell University suggests that as many as 40% of all deaths worldwide are linked to soil, water, and air pollution. Air pollution from smoke and various chemicals kills 3 million people a year worldwide. In the United States alone about 3 million tons of toxic chemicals are released into the environment -- contributing to cancer, birth defects, immune system defects and many other serious health problems. Source: Pimentel, David. Cornell University. 2007.
Water and Air Pollution Air Pollution / Photochemical Smog • Ground-level Ozone • Volatile Organic Compounds (VOCs) • Particulate Matter (ash, smoke, dust, pollen) Soil Contamination • Acid Deposition/Acid Rain • DDT • Heavy Metals Water Pollution • Minamata Disease (methylmercury contamination) • bioaccumulation • Eutrophication and Dead Zones (excess nitrogen)
Air Pollution / Photochemical Smog Ground-level Ozone Volatile Organic Compounds (VOCs) Particulate Matter (ash, smoke, dust, pollen)
Air pollution • Role of physical geography • Prevailing winds • Topography and inversions • Role of cultural geography • Use of fuels and solvents related to level of urbanization, industrialization, and regulations • Disruption of soil linked to particulate matter
Air pollution • A photochemical smog is the chemical reaction of sunlight, nitrogen oxides (NOx) and volatile organic compounds (VOCs) in the atmosphere, which leaves airborne particles (called particulate matter) and ground-level ozone. • 3 million deaths worldwide
Air Pollutants Defining Dirty Air • Smog is the general term used to describe a variety of air pollutants, including ground-level ozone (smog's main ingredient), particulate matter, carbon monoxide and nitrogen oxides. It refers to air pollution that is formed when gases from many sources are released into the air and chemically react with each other in sunlight. • Ocean breezes sweep the smog inland toward the mountains where an inversion layer of warm air pushes it down, trapping the smog close to the ground where we live and breathe. Ground-level ozone (O3) is a colorless, odorless pollutant formed by a chemical reaction between volatile organic compounds (VOCs) and oxides of nitrogen (NOx) in the presence of sunlight. The primary source of VOCs and NOx is mobile sources, including cars, trucks, buses, plus agricultural and construction equipment. Particulate matter (PM) is the term used for a mixture of solid particles and liquid droplets found in the air. It originates from a variety of sources, including motor vehicles, power plants, construction activities, soil dust, soot and industrial processes. Coarse particles (PM10) are generally emitted from sources such as windblown dust, vehicles traveling on unpaved roads, and crushing and grinding operations. Fine particles (PM2.5) can come from fuel combustion (motor vehicles, power generation, industrial facilities) and fugitive dust. PM2.5 is formed primarily in the atmosphere from gases such as sulfur oxides, NOx, and VOCs. Carbon monoxide (CO) is a colorless, odorless gas by-product of combustion produced primarily by motor vehicles. Burned wood and charcoal also emit carbon monoxide.
Ground-level Ozone – from combustion of fuels • Ozone is a strong irritant that can constrict the airways, forcing the respiratory system to work harder to provide oxygen. It also can cause: • Aggravated respiratory diseases such as emphysema, bronchitis and asthma • Damage to deep portions of the lungs, even after symptoms such as coughing or a sore throat disappear • Wheezing, chest pain, dry throat, headache, or nausea • Reduced resistance to infection and increased fatigue Particulate Matter – PM 2.5 (from combustion) and PM 10 (from loose dust) • A series of scientific studies have linked particulate matter, especially fine particles, with a variety of significant health problems: • Aggravated asthma, heart, or lung disease • Respiratory-related hospital admissions and emergency room visits • Acute respiratory symptoms, including severe chest pain, gasping, and aggravated coughing • Decreased lung function which can be experienced as shortness of breath • Chronic bronchitis • Premature death Carbon Monoxide – from combustion of fuels and wood • Carbon monoxide replaces oxygen in the body's red blood cells. People with heart disease are more susceptible to developing chest pains when exposed to low levels of carbon monoxide. Exposure to high levels of carbon monoxide can: • Slow reflexes and cause confusion and drowsiness • Result in death in confined spaces (i.e., an enclosed garage) at very high concentrations
Controlling Los Angeles Smog with Technology? Since smog was first recognized as a serious problem in 1947, inventors and engineers have proposed innovative ideas to get rid of it. • One was to connect all Los Angeles industries to a massive network of concrete exhaust pipes routed to the mountains where pollution could be released above the inversion layer. If it works for sewage, it will work for air pollution, thought the engineering firm that pioneered the "air sanitation system" concept. But the system would have required 89 miles of ductwork and the energy to move the large volumes of air would have been several times beyond what Hoover Dam could supply. Many other ideas surfaced in the 1950s and 1960s to purify, ventilate or wash the air over Los Angeles. • One was to cut holes in the mountains and install huge exhaust fans to blow smog out of the basin. However, blowing or washing away smog proved to be impractical since it involved a land mass of 1,600 square miles and over 200 million tons of air. The enormous energy requirements made the idea impossible. • One scientist suggested blackening whole sections of the eastern mountains so as to store heat and create thermal currents and westerly winds that would blow smog over the mountains
Particulate matter • Source: incomplete burning of fuel • Respiratory problems • Short transport distance • Closest to source = most affected
Photochemial smog • Sources: incomplete burning of fuel • Nitrogen dioxide, hydrocarbons, and sunlight • Forms ozone at ground level • Respiratory problems, damage to plants
How to Control Los Angeles Smog? • 1970 Clean Air Act (amended repeatedly until 1990) sets standards for 6 key pollutants. States then implement plans to comply. • Key elements in California have been automobile smog checks, more refined gasoline required statewide, smokestack scrubbers which catch particulate and oxides of nitrogen and sulfur. • New management plans call for increased use of cleaner solvents that release fewer volatile organic compounds (VOCs). Dry cleaning, manufacturing, etc.. • Scrubbers use lime or ammonia to remove NOx and SOx • Catalytic converters on automobiles remove NOx
Acid rain • Source: burning fossil fuels • Sulfur from coal becomes sulfuric acid • Terrestrial effects (forests, soils) • Aquatic effects (death of fish) • Material effects (buildings, monuments)
Sources of Acid Depostion Sources of nitrogen oxides (NOx) Sources of sulfer oxides (SOx)
Damage to vegetationDamage to vegetation and the dying of forests have long been associated with acid rain. The washing out of metal ions results in limited plant nutrients. Vegetation exposed to acid rain will therefore absorb less of these essential nutrients. The result is poorer quality of a plant’s proteins, stunted growth and exposure to diseases. Death of fishDeath of fish is the best known effect of acidification, and is therefore a reliable and frequently used indicator. There are two reasons for the death of fish. When the acidification reaches a certain level, the fry die. The most sensitive species are trout and salmon.