Water Pollution PDF

Pollution is the introduction of a contaminant into the environment. It is created mostly by human actions but can also be a result of natural disasters. Polluted environment consists of solid wastes, polluted water, disease germs, diseased plants, and animals, etc.  The area covered by the po...

Pollution is the introduction of a contaminant into the environment. It is created mostly by human actions but can also be a result of natural disasters. Polluted environment consists of solid wastes, polluted water, disease germs, diseased plants, and animals, etc.  The area covered by the pollution is going on increasing. The polluted environment has been degrading the healthy environment. Such places are not suitable to live in, sometimes people are forced to migrate somewhere. Because humans are at the top of food chain, they are particularly vulnerable to the effects of non-degradable pollutants Water Pollution Water pollution is the contamination of water bodies (e.g., fakes, rivers, oceans, aquifers, and groundwater) Water pollution occurs when pollutants are discharged directly or indirectly into water bodies without adequate treatment to remove harmful compounds.  Itis defined as the addition of any substances to water or changing of water's physical and chemical characteristics in any way which interferes with its use for legitimate purposes.  Water is never pure in a chemical These include dissolved gases (H25, CO2, NIES, NZ, dissolved minerals (Ca, Mg, Na, and salts), suspended matter (clay, silt, sand) and even microbes. 1. Petroleum Products Oil and chemicals derived from petroleum substances are used for fuel, lubrication, plastics manufacturing, and many other purposes. These petroleum products get into water mainly by means of accidental spills from ships, tankers, trucks, pipelines, and leaky underground storage tanks.  Many petroleum products are poisonous if ingested by animals. Spilled oil damages the features of birds or far of animals often caning death in addition, spilled oil may be contaminated with other harmful substances, such as polychlorinated biphenyls (PCB) 2. Pesticides and Herbicides Pesticide-are substances that are meant to control pests. Herbicide- are substances used to kill unwanted plants Chemicals used to kill pests and weeds, for instance, in farms or in suburban yards, may be collected by rainwater runoff and carried into stream, especially if these substances are applied too lavishly. Some of these chemicals are biodegradable and quickly decay into handless or less harmful forms, while others are non-biodegradable and remain dangerous for a long time When animals consume plants that have been treated with certain non-biodegradable chemicals, such as, chlordane and Dichlorobiphenyl trichloro ethane (DOT), these chemicals are absorbed into the tissue or organs of the animals. Many drinking water resources and supplies are contaminated with pesticides from widespread agricultural use. Nitrates, a pollutant often derived from fertilizer runoff, can cause methemoglobinemia in infants, a potentially lethal form of anemia i.e., also called blue body syndrome 3. Heavy Metals Heavy metals, such as copper, lead, mercury and selenium, get into water from many sources including industries, automobile exhaust, mines and even natural soil. When they teach high levels in the body, heavy metals can be immediately become poisonous or can result in long- term health problems like those caused by pesticides and herbicides. For example, cadmium in fertilizer derived from sewage sludge can be absorbed by crops. If these crops are eaten by humans, the metal can cause diarrhea and vomiting, liver and kidney damage. Lead can get into water from lead pipes and solder in older water pipe systems, children exposed to lead in water can suffer mental retardation. 4. Hazardous Wastes Hazardous wastes are chemicals wastes that are toxic, reactive, corrosive, or ignitable (farmable). If improperly treated or stored, hazardous wastes can pollute water supplies. In 1969, the Cuyahoga River in Cleveland, Ohio, was so polluted with hazardous wastes that it caught fire and burned PCBs. 5. Excess Organic Matter Fertilizers and other nutrients used to promote plant growth on farms and in gardens may find their way into water. The excess organic matter that present to the water may cause eutrophication. Oxygen levels in the water may drop to such dangerously low levels that oxygen-dependent animals in the water, such as fish, may die. This process of depleting oxygen to deadly levels is called eutrophication BORACAY 6. Sediments Sediments, soil particles carried to a stream bed, lake or ocean can also be pollutants if they are present in a large amount. Soil erosion produced by the removal of soils trapping trees near water ways, or carried by rain water and flood water from crop plantations, strip mines and roads can damage a stream or lake by introducing too much nutrient matter. This leads to eutrophication Sedimentation can also cover stream bed gravel in which many fishes such as salmon and trout lay their eggs  Sediment particles absorb warmth from the sun and thus increase water temperature. This can stress some species of fish. 7. Infectious Organisms A 1994 study by the center for disease control prevention (CDC) estimated that about 9,000,000 people get sick usually in the United States because of organisms in their drinking water and around 900 people die. Many diseases organisms that are present in small members in most natural water are considered pollutants when found in drinking water. Such parasites as Cardia, lamblia and Cryptosporidium parvum occasionally tum up in urban water supplies. These parasites can cause illness, especially in people who are very old or very young and in people who are already suffering from other diseases 8. Thermal Pollution Water is often drawn from rivers, lakes or oceans for the use as a coolant in factories and power plants. Such water is usually returned to the source warmer than it was taken. Even a small temperature changes in a body of water can drive away the fish and other species that are originally present and attract other species in place of them  ] Thermal pollution can accelerate biological processes in plants and animals or deplete oxygen level in water. The result may be death of fish and other wildlife near the discharge source Thermal pollution can also be caused by the removal of trees and vegetation Thermal pollution is defined as a sudden increase or decrease in temperature of a natural body of water. 1. Domestic wastes and sewage contains many micro-organisms or disease-causing agents which may cause typhoid, cholera, dysentery, jaundice, itching etc. such organisms also utilize dissolved oxygen of water which directly affects other aquatic animals Domestic waste waste that is generated because of the ordinary day-to-day use of domestic premise (solid waste) such as paper, cardboard, wood, etc.  Sewage type of wastewater that is produced by a community of people (liquid waste)  Typhoid is a bacterial infection that can lead to a high fever, diarrhea, und vomiting. It can be fatal. It is caused by the bacteria Salmonella typhi. The infection is often passed on through contaminated food and drinking water, and it is more prevalent in places where handwashing is less frequent.  Cholera-is an infectious disease that causes severe watery diarrhea, which can lead to dehydration and even death if untreated. It is caused by eating food or drinking water contaminated with a bacterium called Vibrio cholerae.  Dysentery is an infectious disease associated with severe diarrhea.  Jaundice is a condition in which the skin, sclera (whites of the eyes) and mucous membranes turn yellow.  This yellow color is caused by a high level of bilirubin, a yellow-orange bile pigment. Bile is fluid secreted by the liver.  Bilirubin is formed from the breakdown of red blood cells. Itching is an irritating sensation that makes you want to scratch your skin 2. Domestic wastes and sewage create foul smell which makes water unfit for many purposes. It also increases algal blooms due to which organic matter is increased 3. Inorganic compounds of nitrates and phosphates increase the rate of eutrophication 4. Detergents from washing and bathing are slow degrading substances, hence the effect of which remain for long periods 5. Thermal pollution increases water temperature, and the hot water can hold less oxygen. It changes life in water. While trout eggs cannot produce fingerlings due to failure in hatching, they are reduced 6. Oil, when spread over surface of water, decreases its oxygenation so that aquatic animals are badly affected. It may catch fire and harm all organisms in water. It kills sea birds 7. Muddy water caused by run water cut off sunlight for submerged plants. This causes reduction in dissolved oxygen which ultimately leads to the reduction of aquatic organisms 8. Cadmium obtained by industries causes kidney damage, hypertension, anemia and damage to placenta Cadmium's major use is in batteries (especially rechargeable nickel-cadmium, NiCad, batteries)  Chronic kidney disease, also called chronic kidney failure describes the gradual loss of kidney function.  Hypertension, also known as high blood pressure, is a long-term medical condition in which the blood pressure in the arteries is persistently elevated  Anemia is a condition in which you lack enough healthy red blood cells to carry adequate oxygen to your body's tissue  9. Compounds of lead and mercury are slow poisonings which cause skin diseases, anemia, headache, loss of muscular power and irreversible brain damage  Headache is defined as a pain arising from the head or upper nock of the body. 1. Use of pesticides and insecticides should be controlled or reduced. In such chemicals, degradable and less stable materials should be used so that toxic effect would be prevailing. Pesticide-are substances that are meant to control pests Insecticide -a substance used for killing insects. 2. Hot effluents from industries should be controlled before disposing to the hot water body. 3. Domestic wastes should be converted into compost rather than throwing into the sources of water. 4. Toxic substances of sewage pollutants should be converted into non-toxic substances by treatment. 5. Water hyacinth is a biological mean to reduce water pollution. It can also filter out heavy metals like lead, mercury, cadmium, and toxic substances. 6. There should be provision of monitoring effluents from industries before mixing them in the water body. Some rules should be created and enforced to treat such wastes to a certain standard before releasing them. 7. Soil erosion, floods and landslides are to be controlled so that sources of water may not be polluted 8 People's awareness should be developed regarding polluted water which has adverse effects on the health of the living creatures. 9. Banning or more strictly regulating disposal of hazardous waste in deep injection wells and landfills 10. Planting buffers zones of vegetation between cultivated fields and nearby surface water. 11. Controlling human pollution. 12. Managing solid waste and liquid waste properly. Water purification is the process of removing undesirable chemicals, material, and biological contaminants from raw water The goal is to produce water fit for a specific purpose. The purification processes of water may reduce the concentration of matter including suspended particles, parasites, bacteria, algae, viruses, fungi, and a range of dissolved and particulate materials derived from the surface that the rainwater might have come in contact with. 1. Flocculation Flocculation is a process which clarifies water. Clarifying means removing any turbidity or color from water. Clarification is done by causing a precipitate to form in the water, which can be removed using simple physical methods. Initially, the precipitate forms a very small particle but as the water is gently stirred, these particles stick together to form bigger particles. This process is sometimes called flocculation. Initially, the precipitate forms a very small particle but as the water is gently stirred, these particles stick together to form bigger particles. This process is sometimes called flocculation. 2. Sedimentation Water exiting the flocculation basin may enter the sedimentation basin, also called a clarifier or settling basin. It is large tank with slow flow, allowing flock to settle to the bottom The sedimentation basin is best located close to the flocculation basin so that the transit between does not permit settlement or flock break up. Sedimentation basins can be in the shape of a rectangle where water flows from end to end or circular where flow is from the center outward Sedimentation basin outflow is typically over a weir, so, only a thin top layer-furthest from the sediment-exists 3. Boiling Boiling kills bacteria as well as other discase-causing microorganisms like Giardia, lamblia and Cryptosporidium parvum which are commonly found in rivers and lakes. Water temperature above 70°C will kill all pathogens within 30 minutes, above 85°C within a few minutes, and at boiling point (100°C), most pathogens will be killed, excluding certain pathogens and their spores, which must be heated to 118° Celsius (e.g.: botulism-Clostridium botulinum). This can be achieved by using a pressure cooker because regular boiling will not heat water past 100°C. Boiling is the action of bringing a liquid to the temperature at which it bubbles and turns to vapor and kills bacteria as well as other disease-causing microorganisms. 4. Filtration Portable pump filters are commercially available with ceramic filters that filter 5,000 to 50,000 liters per cartridge, removing pathogens down to the 0.2-0.3 micrometer range. Some also use activated charcoal filtering. Filters of this kind remove most bacteria and protozoa, such as Cryptosporidium parvum and Giardia, lamblia, but not viruses except for the very largest of 0.3 micrometer and largest diameters. So, disinfection by chemicals or ultraviolet light is still required after filtration. 5. Chlorination The most common disinfection method involves some form of chlorine or its compounds such as chloramines or chlorine dioxide. Chlorine is a strong oxidant that rapidly kills many harmful micro- organisms. Because chlorine is a toxic gas, there is a danger of release associated with its use. This problem is avoided by the use of sodium hypochlorite, which is relatively inexpensive solution that releases free chlorine when dissolved in water. Chlorine solutions can be generated on site by electrolyzing common salt solutions. 6. Solar water disinfection (SODIS) In solar water disinfection (SODIS), microbes are destroyed by temperature and UVA radiation provided by the sun. Water is placed in a transparent plastic PET bottle, which is first oxygenated by shaking partially filled capped bottles prior to filling the bottles all the way. The completely water-filled and capped bottles are exposed to sunlight, preferably on a corrugated metal roof, slanted slightly to maximize the exposure to solar radiation. In practice, the water-filled bottles are placed for six hours in full sun or for two days in partial sunlight for weather conditions involving partially overcast days, which raises the temperature