Biological Pollution
Biological pollution is anything that could be considered organic that is detrimental to our water supply. These can be bacteria, viruses, protozoans, and worms that can be carried by water from one host to another, which can cause terrible waterborne diseases such as cholera, bacterial infections, and harmful parasites that can cause symptoms such as fever and diarrhea. Another form is foreign invasive species, and even algae, if it is in large enough numbers. These can come from a multitude of sources, but mostly from agricultural runoff, a nonpoint source, containing fertilizers and decomposing organic matter that can come from barnyards. Untreated human sewage that comes from our homes can also cause a rise in harmful bacteria and viruses, which can count as a point source. Invasive species can also count as biological pollution. These species have been introduced to many places all throughout the world, mostly because of people. However, there is no way to classify this as either a point or nonpoint source. Some are small and innocuous. An example of this is the Mediterranean gecko (Hemidactylus turcicus). This small gecko, native to the Mediterranean region, has no detrimental effects to Florida, its natural environment. However, invasive species are often very detrimental to the environment. Cane toads (Bufo marinus) are currently devastating Australian environments. They were introduced into Australia in order to rid agricultural land of a destructive beetle. However, instead of eating the beetles, they bred prolifically and destroyed many populations of animals, many of which are now endangered. The toads are poisonous and only have one species of snake that eats it in Australia. This is a classic example of an invasive species being detrimental towards the environment. A way to limit the amount of biological pollution, most specifically algal blooms and bacteria, is to prevent runoff from fields and lawns in order to limit the flow of fertilizers and animal waste into rivers, and subsequently, into oceans and lakes.
Chemical Pollution
Chemical pollution is anything inorganic that might be introduced to rivers, lakes, or streams. Interestingly enough, many of the chemical pollutants, most notably dissolved metals, occur naturally in the water already in small concentrations. It is only when concentrations become elevated do they become harmful. Most chemical pollutants come from industrial work that may be carried in rain runoff, making it a non-point source. Some more examples of chemical pollutants include chemical solvents, pesticides, and oil. Metals and solvents can work their way into an organism’s body and cause the organism to become stunted or infertile. An endangered population composed of only infertile animals would be devastating. Pesticides can cause eutrophication, when algal blooms destroy habitats and deplete the water of nutrients and oxygen. The poison flows through the levels of predator-to-prey, like from poisoned fish to poisoned hawk. Oil spills, one of the most devastating forms of chemical pollution, can cause mass fish death and stick to the feathers of birds, rendering them unable to fly. Chemical pollution can also come from a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiM6TDjLA1v047jSjYZWeGaAx1vnShRv5MGZPLe-68yZFY_OaHdyF9u7Mi1MxXuOUrc0-MrYHh-52WNu5MBY_YFSDQT2vFCylaruL5fNC4QoTj5QMOWJVvfxlpsTVrW_O_5S59l_YoV2po/s1600/fertilizer.jpg">
Thermal Pollution
Thermal pollution usually occurs in rivers or at dams where factories or energy plants discharge warm or hot water into the moving water, making it a point source.. Large numbers of fish, shellfish, and crustaceans die if exposed to raised water temperatures for an extended period of time. This is because their bodies cannot metabolize properly under these conditions. Fish, especially, can die because their bodies cannot take sudden changes in water temperature. HOWEVER – raised water temperature is not bad for all species. Sea turtles found off the California coast have been found to congregate near electrical discharge factories. This is because the warm water increases the growth of algae and sponges, some of their main food items. Even so, this causes a disruption in balance, and a way to stop thermal pollution is for factories to install cooling systems so they can cool down the wastewater they discharge into the surrounding area.
Physical Pollution
Physical pollution is any input of physical foreign object into a water supply. This can include garbage, plastic, food wrappers, aluminum cans, etc. Most of the time, this can be classified as a direct point source. One of the most common physical “pollution” done by man is in freshwater – i.e., dams. Dams are currently threatening thousands of species across the world, and has already helped to cause the extinction of at least one precious marine mammal. This was the baiji, which was one of five species of rare river dolphins worldwide. It was endemic to the Yangtze River in China. It was proclaimed extinct in 2006 when 2,175 miles of this river was searched, to no avail. Shorelines are also being destroyed through the construction of groins, jetties, and other shoreline structures. Current stacks sand up on the side where the current is coming from, and deprives the other side of sand. There isn’t much we can do to stop this kind of pollution, other than throw away your garbage and recycle recyclable things.
Ways To Detect Pollution
There are many ways to detect each sort of pollutant. For biological pollutants, the most effective way of detecting that is by biological indicators, as most biological pollutants have the greatest effect on endemic species and humans that drink the water. Anomalies in fish and illness in humans are the two leading factors in detecting a biological pollutant. The way of detecting chemical pollutants is by chemical tests. A sample of water can be taken into a lab, and its level of pollutants can be measured. This can tell officials if the body of water has a dangerous level of pollutants, making it unsafe to eat, fish, swim, or use the water to drink from. Detecting thermal pollutants work the same way, only by measuring the temperature of the water and comparing it to past water temperatures to see if it has risen any. Physical pollutants can be detected almost always by sight.
Health Risks
Each pollutant has a multitude of health risks that not only affect the environment, but humans, also. Biological pollutants such as parasites can cause many waterborne diseases such as cholera and malaria, which often end in death. Though the risk of this is not nearly as high in places such as the United States where most water is filtered, drinking contaminated water and eating contaminated fish can cause serious illness. This can be avoided easily by installing working water filtration devices.
Chemical Chemical wastes carry many cancer-causing carcinogens, and chemicals that can cause harmful mutations in high doses. Companies could prevent this by regulating runoff, but so far there isn’t a totally effective way to stop chemical pollution altogether.
Thermal waste, though it doesn’t have any direct harmful effect on humans, can be dangerous because it weakens the immune system of many fish that live in heated waters due to stress. This causes them to contract diseases much easier than they would have normally, and eating contaminated fish can, as it was said before, serious illness. The factories that heat the water can create measures to cool down the wastewater they use in order to prevent this.
Physical waste, though not particularly harmful to humans except in the case of feces, which carries harmful parasites and bacteria such as roundworms and E. Coli, have a particularly adverse effect on the environment, due to the fact that seabirds and fish can choke on plastic pieces that look like food. This is easily the most preventable type of pollution. A way to seriously slow the amount of physical waste that goes into our waterways is to simply recycle and throw away our garbage when finished with them.
Socioeconomics greatly determines what kind of pollutants goes into our waterways. Industrial countries, most notably China, have higher concentrations of chemical pollutants than others whose economies don’t depend as much on factories. That, plus the fact that many rural Chinese homes do not have water filtration systems strong enough to filter these pollutants out, causes China to have one of the highest concentrations of illness related to industrial water. In third-world countries, people are more susceptible to biological pollutants for the same reason, such as in Africa, where malaria and cholera run rampant. The environment also has a part in it. Rising ambient temperatures cause water temperatures to rise naturally, and that plus human activity causes thermal pollution to rise drastically. Culture also determines how pollutants in water affect humans. In Africa, the reason many people stay in the bush is because of tradition and the fact their ancestors had been there for thousands of years. This devotion to their culture prevents them from getting much money, and thus prevents them from getting the tools they need to filter water properly. This leaves them highly susceptible to things like biological and chemical pollutants.
Works Consulted
Library Thinkquest: Water Pollution. (n.d.) Retrieved from http://library.thinkquest.org/04oct/01590/pollution/pollutants.html
April 13 2010
Water Pollution Guide. (2008) Retrieved from http://www.water-pollution.org.uk/chemical.html
April 8 2010
National Geographic: China’s Rare River Dolphin now Extinct, Experts Announce. (14 December 2006) Retrieved from http://news.nationalgeographic.com/news/2006/12/061214-dolphin-extinct_2.html
April 8 2010
Pollution Issues: Thermal Pollution. (n.d.) Retrieved from http://www.pollutionissues.com/Te-Un/Thermal-Pollution.html
April 8, 2010
Environmental Pollution Centers: Chemical Pollution. (n.d.) Retrieved from http://www.environmentalpollutioncenters.org/chemical/pollutants/
April 12 2010
Zebra Mussels. (n.d.) Retrieved from http://www.statemaster.com/encyclopedia/Zebra-mussels
April 12 2010
Water Pollution: An Introduction. (16 July 2009) Retrieved from http://www.explainthatstuff.com/waterpollution.html
April 12, 2010
Coral Reef Bleaching. (1998) Retrieved from http://www.marinebiology.org/coralbleaching.htm
April 12, 2010
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