Friday, December 6, 2019

Smog Essay Example For Students

Smog Essay Smog has been around for a pretty long time, people just knew it as something else. Smog comes from the word smoke and fog, and thats practically what it is. It was a serious problem before, before nature and humans went unharmed in the presence of smog but now its serious. What does all of this polluted air do to the body? The answer depends on the situation. How long a person is exposed to pollution, the type and concentration, the place, time and day, temperature, weather and more. But one thing is certain: Smog is harmful to your health. Lungs are ozones primary target. Studies on animals show that ozone damages cells in the lungs airways, causing inflammation and swelling. It also reduces the respiratory systems ability to fight infection and remove foreign particle. Ozone may pose a particular health threat to those who already suffer from respiratory problems such as asthma, emphysema and chronic bronchitis. About 10% of the basins approximately 14 million residents fit into t his category. Ozone may also pose a health threat to the young, elderly and cardiovascular patients. Ozone affects healthy people as well. In 1990, the State Air Resources Board established a new health advisory level in response to mounting evidence that smog affects healthy, exercising adults at lower levels than previously believed. Now, a health advisory is issued at .15 parts per million (on the pollutant standards index) before a first stage smog alert is called when ozone levels reach .20 ppm. During a health advisory, everyone, including healthy adults and children are advised to avoid prolonged, vigorous outdoor exercise. Susceptible individuals, including those with heart or lung disease, should avoid outdoor activities until the advisory is canceled. Currently, the federal Environmental Protection Agency is reviewing the adequacy of the federal health standard for ozone and is considering tightening it. The sources of pollution include emissions from on-road vehicles, non-road vehicles like planes, ships and trains, industries, and even small businesses and households where polluting products are used. Ozone, an invisible gas, is not emitted directly into the air, but forms when nitrogen oxides from fuel combustion and volatile organic gases from evaporated petroleum products react in the presence of sunshine. Ozone levels are highest during the warm months when there is strong sunshine, high temperatures and an inversion layer. Nitrogen oxides are produced when fossil fuels are burned in motor vehicles, power plants, furnaces and turbines. Carbon monoxide is a by-product of combustion that comes almost entirely from motor vehicles. Fine particles, which are emitted directly as smoke and diesel soot and form in the air out of nitrogen oxides and sulfur oxides, obscure visibility and can be inhaled deep into the lungs. During the early years of World War II, Los Angeles residents began to realize the consequences of an increasingly industrialized area. Investigations began to determine the cause of residents eye irritation, crop damage, severe reductions in visibility and the rapid deterioration of rubber products. Smog became a familiar word and everyday presence and scientists and medical personnel began to look at its effects on public health. In the mid-1950s, the state of Californias Public Health division started to step up its efforts to define the problem of how and where smog forms, as well as address the health concerns associated with exposure to smog. Ozone levels were reaching peaks of .68 parts per million, more than six times the federal health standard. Early efforts to study the health effects of exposure to air pollution focused on acute exposure episodes. Only recently have the long-term exposure effects been addressed. In a 1956 survey sent out by the Los Angeles County Medical Association, physicians reported the following: There have been several episodes in history which illustrate the harmful effects of acute short-term exposure to air pollution. Among those include: During a five-day fog in December 1930, 63 people died, most of the deaths occurring on the fourth and fifth days. Older persons with previously known diseases of the heart or lungs accounted for the majority of fatalities. The signs and symptoms were primarily those caused by a respiratory irritant. They include chest pain, cough, shortness of breath and irritation of the eyes. Sulfur dioxide gas is suspected as the cause of the disaster. Twenty people died and approximately 7,000 or 50% of the population, experienced acute illness during the week of Oct. 25, 1948, when temperature inversion and air stagnation occurred. Persons of all ages became ill, but those over 55 were more severely affected. Those with previous heart or respiratory disease, particularly bronchial asthma, suffered m ost. Symptoms were primarily respiratory and secondarily gastrointestinal, and included cough, sore throat, chest constriction, shortness of breath, eye irritation, nausea and vomiting. The onset of the illness for most persons occurred on the evening of the third day. Of the 20 who died, 14 had some known heart or lung disease. Three episodes during which heavy fogs and air pollution were associated resulted in the death of nearly 5,000 people in 1948, 1952 and 1956. The episode in December of 1952 alone, resulted in at least 3,000 deaths more than expected for that time of year. Although the increase was present in every age group, the greatest increase was in the age group of 45 years and over. More than 80% of these deaths occurred among individuals with known heart and respiratory disease. During each of these incidents, comparable conditions were present: limited air supplies as a result of low-lying temperature inversions and faint winds, and a continuing heavy output of air pollution from multiple sources. Also, in none of the incidents was technology sophisticated enough to properly monitor the air and diagnosis of the specific causes of the illness and deaths were based on limited evidence gathered after the disasters. Unemployment In Europe: Its Impact In The Future O EssayThere have been many Environmental Protection Agency studies looking at health effects. Some findings include: oA study of 10 adult men exposed to .12 ppm ozone for 6.6 hours (including five hours of moderate exercise), found that lung function decreased and respiratory symptoms (coughing and breathing discomfort) increased over the more than six hours of exposure. In a study done on rats, continuous low level exposure to ozone caused restrictive lung disease. Removal of the rats from the ozone environment to one of clean, filtered air appeared to reverse the disease state back to normal. However, the study indicated that since people do not breathe filtered air, ozone exceedances in numerous cities would appear to promote pulmonary fibrosis. In a field study of children during normal activities at summer camp, lung function measurements were taken before, during and after ozone levels reached above .12 ppm on four days and .1 8 ppm on one day. Lung function failed to return to its pre-episode level for many days after the ozone episode had passed. An acute exposure of humans to .40 ppm ozone initiates biochemical changes in the lung resulting in the production of components which contribute to inflammation and acute lung damage and which can lead to long term effects such as fibrosis. A study was initiated to determine if prolonged exposure to low levels of ozone would produce similar biochemical changes. Non-smoking males were randomly exposed to filtered air and either .10 ppm or .08 ppm of ozone for 6.6 hours with moderate exercise. The study concluded that exposure of humans to low levels of ozone is sufficient to cause an inflammatory reaction in the lungs. The California Air Resources Board has concluded that since the lungs of children are not fully developed, early damage to the respiratory tract could increase the risk of respiratory disease in adult life. Because of their physiology, children are much more likely than adults to develop smog-related lung damage. For their body size, children inhale several times more air than adults, and they breathe faster, particularly during strenuous physical activity. In addition, they spend more time outdoors than any other segment of the population according to the AQMD study. Dr. Robert F. Phalen, Ph.D., professor of community and environmental medicine and director of the Air Pollution Health Effects Laboratory at the University of California, Irvine, says that when children exercise, they tend to breathe through their mouths. According to Phalen, mouth-breathing bypasses the natural filtering of air pollutants by the nose and allows large volumes of polluted air to affect the more sensitiv e areas of childrens lungs which are still developing. Studies show that children exposed to summer ozone pollution year in, year out, have a greater susceptibility to respiratory infections because chronic exposure to smog impairs their immune system. Research findings also suggest that, even if children do not show symptoms while exercising in unhealthful air, they are likely to suffer a loss in lung function compared to youngsters who grow up where the air is less polluted. State and federal governments have set health standards for pollutants, specifying levels beyond which the air is unhealthful. Californias state standards for air pollutants are more stringent than the federal governments. It is up to each individual state to determine if they want to set tougher standards. Standards are set to provide an adequate margin of safety in the protection of public health. Under the federal Clean Air Act, EPA must base standards solely on health considerations and not economics or technology. Various levels of smog episodes are reported for the pollutant ozone. The declaration of a first, second or third stage smog alert is based on the degree of health risk. The protective actions help to reduce exposure to unhealthful levels of ozone, but those who are especially sensitive should contact their physician for more specific advice. Generally, in the event of a smog alert, outdoor activities should be scheduled for morning or early evening hours to avoid the mid-day peak when ozone levels are at their highest. My opinion on the problem is that it is a very serious problem and something should be done. The only thing is, nothing jurastic enough will be done. People cant just all of the sudden stop using cars and humans cant just all of the sudden change their way of living. So smog and ozone levels will get worse but life will go on. Bibliography:www.smog.com

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