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Effects of air pollution. P rof Madi Jagbeer. 1- The effects of pollutants on Human being. ** the health impact of pollutants ( in brief )
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Effects of air pollution Prof MadiJagbeer
** the health impact of pollutants ( in brief ) The effects of air pollutants involve a large variety of illnesses, starting with the simple irritation of eyes, nose mouth and throat or reduced energy levels, headache and dizziness, but also involving more serious conditions of which the most common are:
Respiratory and lung diseases including: 1- Asthma attacks 2-Chronic Obstructive Pulmonary Disease –COPD 3-Reduced lung function 4-Pulmonary cancer – caused by a series of carcinogen chemicals that through inhalation 5-Mesothelioma – a particular type of lung cancer, usually associated with exposure to asbestos (it usually occurs 20-30 years after the initial exposure) 6-Pneumonia
Air borne disease Airborne diseases are those caused by pathogens and transmitted through the air as very small, or large particles . Disease-causingpathogens are organisms that spread from an infected person to another through coughing, talking and sneezing - even breathing and laughing! According to the U.S. Centers for Disease Control, flu droplets can travel up to six feet away!
**How long these organisms can survive outside the body depends on the type of organism and the conditions of the air, such as its humidity and temperature. **here are three main types of organisms that can cause airborne diseases, including viruses, bacteria and fungi
Along with harming human health, air pollution can cause a variety of environmental effects: • Acid rain. • Eurtophication. • Global climate change. • Depletion of ozone layer.
1. Acid Rain: • Harmful gases like nitrogen oxides and sulfur oxides are released into the atmosphere during the burning of fossil fuels. When it rains, the water droplets combines with these air pollutants, becomes acidic (pH =5.6 or less) and then falls on the ground in the form of acid rain. Acid rain can cause great damage to human, animals (like fish in lakes)and crops.
2. Eutrophication • Eutrophication is a condition in a water body where high concentrations of nutrients (such as nitrogen and phosphorus)) stimulate blooms of algae, which in turn can cause fish kills and loss of plant and animal diversity (low dissolved O2). Although eutrophication is a natural process in the aging of lakes and some estuaries, human activities can greatly accelerate eutrophication by increasing the rate at which nutrients enter aquatic ecosystems. Air emissions of nitrogen oxides from power plants, cars, trucks, and other sources contribute to the amount of nitrogen entering aquatic ecosystems. It interfere with swimming ,boating and enjoying water bodies.
3 . Global climate change. • The Earth's atmosphere contains a delicate balance of naturally occurring gases that trap some of the sun's heat near the Earth's surface. This "greenhouse effect" keeps the Earth's temperature stable. Unfortunately, evidence is mounting that humans have disturbed this natural balance by producing large amounts of some of these greenhouse gases, including carbon dioxide ,methane ,ozone, and CFCs. As a result, the Earth's atmosphere appears to be trapping more of the sun's heat, causing the Earth's average temperature to rise - a phenomenon known as global warming. Many scientists believe that global warming could have significant impacts on human health, agriculture, water resources, forests, wildlife, and coastal areas.
5. Depletion of Ozone layer • Ozone exists in earth’s stratosphere and is responsible for protecting humans from harmful ultraviolet (UV) rays. Earth’s ozone layer is depleting due to the presence of chlorofluorocarbons, hydro chlorofluorocarbons in the atmosphere. As ozone layer will go thin, it will emit harmful rays back on earth and can cause skin and eye related problems. UV rays also have the capability to affect crops.
The impact of air pollution on animals is more or less similar to that on man. • Emissions from automobiles and industries accumulate in the atmosphere. This gets into animals’ bodies through inhalation of gases and particulate matter, ingestion of contaminated food and water with air pollutants and in the case of certain amphibians, through skin absorption.
Respiratory issues • Gaseous pollutants from automobile exhausts – such as Nitrous Oxide (NO2) from any combustion process and Sulphur Dioxide (SO2) from combustion of sulfur contain fuels– form Ozone (O3) under the action of sunlight. When inhaled, ozone is known to cause respiratory diseases. • The problem may be particularly more pronounced in birds because of the distances they travel and their higher respiratory rates.
Mercury and Fluoride poisoning • Particulate matter such as mercury, fluoride, powdered ash, dioxins and furans etc. are emitted by large industrial complexes and thermal power plants. • These again enter the animals’ respiratory systems and cause particulate buildup in their lungs, eventually choking them to death. Additionally, mercury is known to be a potent poisoning agent. • Fluorides, which are also emitted in gaseous forms From Aluminum factories, get absorbed by plants, and in turn get transferred into herbivores and soil dwelling invertebrates. Several herbivores are known to show signs of fluoride poisoning (in the form of malformed teeth and bones such as in Tunisia and Flurida). • A number of livestock have been poisoned by fluorides and arsenic in North America. Bone lesions (osteoporosis) in animals due to excessive fluorides have also been reported.
4- Effects of Air Pollution on Plants Air pollution has caused widespread damage to trees, fruits, vegetables, flowers and in general, vegetation as a whole. The total annual cost of plant damage caused by air pollution in USA alone has been estimated to be in the range of 1 to 2 billion dollars. The most dramatic early instances of plant damage were seen in the total destruction of vegetation by sulfur dioxide(as seen in the photo) in the areas surrounding smelters.
Air Pollutant deposition to plants 1- gases (Gaseous pollutants may be taken up by plants via stomata or cuticle). 2- wet precipitation. 3- particulate matter. * The effects of pollutants can be observed at various levels of biological system like: a- subcellular, b- cellular, c- plant organ, d- whole plant, e- plant population f- community.
Most commonly, plants can be affected by the following air pollutants: • Sulfur Dioxide: Sulfur dioxide, a by-product of burning fossil fuels such as oil, coal and gasoline, causes changes in the colors of leaf tissue, which may turn white, brown or yellow. • Fluorides:The leaves of some plants like apple are more susceptible to air borne fluorides. Fluorides seem to interfere with the photosynthesis and respiration of plants. • Smogalso causes injury to plants. Chlorine, ammonia, hydrogen sulfide, etc., are also harmful to vegetation. • Similar impact of ozone can be seen in the lesions to plants. Ozone enters plant through stomata during important processes such as photosynthesis and respiration. Common effects of ozone on vegetation include decreased crop yields, and premature defoliation.
Some plants are more susceptible to pollution damage than others. Plants are susceptible to the following: 1- Leaf Damage Chemicals damage the leaves of plants (SO2). If enough leaves are damaged, and If the damage is severe enough, the plant will drop its leaves and the entire plant will die. 2- Slowed Growth Nitrogen dioxide, a byproduct of combustion from car engines or open fires, can slow the growth of plants. Fortunately, rainfall transforms nitrogen dioxide into nitric acid, which adds nitrogen to the soil and actually benefits plants. However, carbon monoxide is less benign. This component of car exhaust is poisonous to humans and will stunt the growth of plants. 3- Insect Infestation Air pollution weakens plants and makes them more susceptible to insect infestation.. A 2008 Newsweek story reported that pine beetles had destroyed 22 million acres of pine trees in Canada and more than 1.5 million acres in Colorado.
