HUMAN ACTIVITIES CAN POLLUTE WATER

Deep cooking pot, water, food coloring, table salt, heavy ceramic mug at least 3 centimeters shorter than cooking pot, plastic food wrap, strong rubber band that can fit around pot, scissors, ice cubes, small sponge 

Wear safety glasses, and avoid the steam produced in tbi s experim ent because steam burns can be particularly harmful. 

Fill the cooking pot with water to a depth of about i centimeter. Add several drops of food coloring and 1 teaspoon of salt to the water and stir. 

Lay plastic wrap loosely across the top of the pot and secure with the rubber band. The seal should NOT be airtight. Instead, leave two opposite edges of the wrap outside the rubber band to prevent a buildup of pressure in the pot as the water is brought to a boil. Use scissors to trim away any wrap hanging below the rubber band. Place an ice cube at the center of the wrap, which should then sag above the mug 

Put on your safety glasses, place your distiller on the stove, and turn the burner on low to bring the water to a low boil. Look for signs of cloud formation below the ice cube. Liquid water condensing here will drop into the mug. Once boiling begins, the mug may jostle. Turn the heat 

Lawns cover 25 to 30 million acres in the United States, an area larger than Virginia. People raking care of these lawns use up to two and a half times more pesti-cidc,s per acre than farmers use on croplands. 

The rate of water contamination from many point sources has decreased markedly since the passing of the Clean Water Act of 1972 and its subsequent amendments. Prior to 1972, the u,ser of a vwiter supply, such as a municipality, was responsible for protecting the supply. Because it is far more efficient to ain-trol water pollutants before they are released into the environment, the Clean Water Act shifted the burden of protecting a water supply to anyone discharging wastes into the water, such as a local industry. 

Another common source of groundwater pollution is sewage, which includes drainage from. septic tanks and inadequate or broken. sewer lines. Animal sewage, especially from factory-style animal farms, is also a source of groundwater (and river water) pollution. Sewage water contains bacteria, which if untreated can cause waterborne disea.ses such as typhoid, cholera, and infectious hepatitis. If the contaminated groundwater travels relatively quickly 

The arrows indicate some major sources of groundwater contamination. 

What is the difference between a point source of pollution and a nonpoint source  

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Human activities, such as agriculture and industry, lead to the pollution of waters due to the input of nutrients and chemicals. Additionally, sewage treatment plants release small, aliphatic organics. The occurrence of such human activities can be seen in the characteristics of the organic carbon content of natural waters. For example, large European rivers (Seine, Rhine, Main) contain significant quantities of... 

Surface Water Naturally available fresh water on the earth s surface in rivers, lakes or wetlands is called surface water. Natural replenishment of surface water takes place through precipitation. Surface water is depleted through natural processes like evaporation, discharge to seas and oceans and sub surface seepage. Human activities can have severe detrimental effects on the quality and availability of surface water. The upper limit of human consumption is restticted by the rate of precipitation within a watershed. Pulling in water from other watersheds through canals or pipelines can increase natural surface water in a particular watershed. Surface water is more prone to pollution from various human actions and needs extensive treatments to make it suitable for human consumption. 

Rain unaffected by human activity contains mostly weak acids and has a pH of 5.7. The primary acid present is carbonic acid, H2C03, a weak acid that results when atmospheric carbon dioxide dissolves in water. The major pollutants in acid rain are strong acids that arise from human activities. Atmospheric nitrogen and oxygen can react to form NO, but the endothermic reaction is spontaneous only at the high temperatures of automobile internal combustion engines and electrical power stations ... 

The monoaromatic compounds benzene, toluene, ethylbenzene and xylene, commonly found in crude oil, are often jointly called BTEX compounds. The most harmful of these compounds is benzene, which is a known carcinogen. BTEX compounds occur naturally near natural gas and petroleum deposits and are detected in the fumes of forest fires. Most of the highly volatile BTEX compounds released by human activity originate from fuel use and end up as pollutants in the air. Inhaling BTEX-polluted air is also the greatest hazard to humans by these compounds. BTEX compounds are water-soluble, and therefore, improper handling can also cause groundwater contamination. 

Pollution of soils and waters by human activities is an important and widespread problem. This pollution by, organic and inorganic substances can affect individual organisms, human populations, and ecosystems, each in its own unique way. In particular former military installations, often used for weapons production and nuclear power plants represent a ongoing and substantial threat to environment and human health because of the specific pollutants that can be released Solvents, explosives, fuels, radionuclides, heavy metals, and metalloids all have been identified in the environment around these installations. Remediation technologies for these contaminated sites have been developed based on conventional systems utilising physical and chemical treatments, such as excavation and incineration, pump-and-treat methods, ultraviolet oxidation, soil washing, etc. 

Human activities harmfully influence the environment and nature in many ways. The production of undesirable wastewater, waste gas, and liquid plus solid residues seems to be inevitable during chemical processes. The public is more sensitive to pollution of the aquatic environment and the depletion of clean water resources, because they have an immediate impact on daily routine and recreational activities. However, air pollution has an adverse impact on our health in the short and long term, and the problems of the greenhouse effect and the destruction of stratospheric ozone could extinguish life from the face of the Earth. These problems are enhanced by overpopulation and urbanization. Today, urban areas can be seen as monsters that consume large amounts of energy, matter, and freshwater and release all kinds of waste into the environment. 

Conservation of aquatic resources cannot be accomplished by avoiding human influences on the aquatic environment. Control of water pollution and protection of the water resource demand more than waste treatment technology. We need to address questions such as these To what extent are the oceans able to absorb wastes without harmful effects Can we improve the fertility of the oceans How can the ecological balance between photosynthetic and respiratory activities in nutritionally enriched but polluted waters be restored Answers to such questions call for a greatly improved understanding of the aquatic environment. 

Air can be polluted by BTEX by combustion of fuels in industrial emissions, vehicle motors, or even by tobacco smoke, and by evaporation from polluted surface water or fuels in gas stations. Analysis of BTEX in air is of special importance because their concentration in urban locations is increasing significantly through human activity. 

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