Water pollution is the contamination of our rivers, lakes, public beaches, and drinking water by unwanted agents known to cause illness, disease, and death. Water pollution can take many forms, originate in a variety of sources, and cause a multitude of problems. The pollution can be biological, such as an unwanted bacteria and parasites. It may be a chemical which is known to cause cancer which has been discharged from an industrial waste site. Water can become polluted from agricultural runoff when toxic herbicides and pesticides mix with groundcover water and enters rivers and lakes. Heavy metals can leach into the water supply when it comes into contact with the drinking water as it is transported from the source to the faucet. The effects can range from a mild inconvenience to serious health problems in humans. It can cause a mildly upset stomach or may result in a terminal illness. Animals and fish, even more sensitive to many pollutants and these toxins, can be placed at risk when the ecological system of our rivers and lakes is disrupted. Whatever form the water pollution takes, it is certain to threaten the food supply, damage recreation areas, and be a major threat to human health.
When toxic chemicals leach or are spilled into the water system the wildlife that depends on that supply suffers. In the case of an oil spill from a tanker, the results are fast and obvious. Wildlife, fish, and birds are immediately threatened with the crude oil sludge. The oily sludge permeates their fur and feathers handicapping any hope of the animal's survival. This form of pollution is highly visible and causes damage that can be easily measured and evaluated. We can readily see the animals die as they encounter this water pollution. However, other types of pollution that threaten our wildlife are not so readily apparent. Industrial chemicals that leach into our water supply, streams, and lakes may not be visible to the human eye. They may not kill fish instantly as the fish survive the moderate levels of the toxins that are present. Many industrial pollutants, however, build up in the fish and wildlife over time. PCBs, a known carcinogen that has been banned, continues to persist in our environment and water supply (Environmental Defense Fund, 2006). Dioxin and heavy metals also have a long term poisoning effect on the fish. When a human eats the contaminated fish, they ingest the pollutants that have been stored in the fish. Consuming this source of food on a regular basis can cause severe health problems and lead to death. Water pollution will eventually poison not only the fish, but also the birds that feed on the fish and the prey that feeds on the birds. This will cause a widespread contamination of our environment and result in many of our food sources being unavailable or unhealthy to eat.
Often times when wastewater from a sewage system is improperly discharged into the environment it contaminates a public area that is used for swimming or recreation. This contaminated wastewater carries potentially dangerous viruses, parasites, and bacteria with it. The U.S. Center for Disease Control (CDC) lists over 20 different types of biological agents known to pollute recreational areas (Nester, Anderson, Roberts, Pearsall, & Nester, 2001). The effects of these waterborne pathogens can be as mild as a case of diarrhea or as serious as meningitis. High fever, liver infection, and birth defects have been traced to water pollution caused by contaminated wastewater discharged into a public lake or beach (Nester et al, 2001). Though these contaminates do occasionally foul our drinking water supply, the most likely contact the public has is at a common recreational area. The CDC documents all reported cases of illness caused by polluted water and found during the period of 1995-1996 of the 12000 cases of disease caused by contaminated water, a full 75 percent were contracted in a public beach or swimming facility (Nester et al, 2001). These statistics show not only the seriousness of the illnesses associated with water pollution, it also points out the widespread scope of the threat to our public beaches.
The far more serious problem caused by water pollution is the presence of odorless and colorless chemicals known to pose a long-term health risk which may result in death. There are over 100,000 different synthetic organic chemicals in use around the world and many of them are present in our supply of drinking water (Nadakavukaren, 2001). Many of these are known to cause cancer, chronic and acute illness, and birth defects. Due to the extreme toxicity of these substances, minute quantities are all that are required to pose a grave health danger. A study in Iowa found that an elevated level of an agricultural herbicide, atrazine, had caused birth defects. While the level was a mere 2.2 parts per million, it was sufficient to cause growth retardation, low birth rates, and premature births (Munger & Hanson, 1997). Other sinister chemicals leach into our water supply through more subtle methods. Lead used to solder copper water pipes can slowly dissolve into the water as the solder corrodes and threaten the person who drinks it with lead poisoning Older homes built before the public's awareness of lead poisoning are particularly at risk due to substandard plumbing and the composition of the solder (Nadakavukaren, 2001). The long term exposure to other chemicals, such as benzene, dioxin, and PCBs, account for a growing increase in leukemia, cancer, and organ disease. Once in the water supply, these chemicals are difficult if not impossible to eliminate. Biological agents that find their way into our drinking water, and if not treated properly, can cause typhoid and cholera epidemics (Guttman, 2001). Yet, the unseen and undetected chemicals that are present in our water supply may pose an even graver threat to the public. Water pollution has indeed been shown to be the source of many illnesses and disease and poses a serious problem to human health
When we pollute the runoff water that enters our streams and rivers, the most immediate effect is on the wildlife and other life forms that are dependent on these areas for habitat. As these toxins make their way into the food chain, the poisons build up and are passed into the human food supply. Wastewater that is improperly handled and discharged can spoil beaches and lakes when they carry agents that can cause severe illness and death. As the population increases and we become more mobile, the chances of encountering a pathogen at a public swimming area increase. Long-term dangers exist when our water supply is contaminated by the myriad of chemicals that are in use today around the globe. These dangerous toxins build up, are not readily apparent, and may take years to manifest into a terminal illness. Whatever form the pollution takes, it can threaten not only our well being but also our appreciation for our environment. Water pollution kills our animals, poisons our food supply and will eventually result in death for many people who are exposed to the dangers of water pollution.
Environmental Defense Fund. PCBs in fish and shellfish (2006). Retrieved April 1, 2006, from http://www.environmentaldefense.org/article.cfm?contentid=3951
Guttman, H. (2001). Drinking water in the post Walkerton era. Environmental Science & Engineering. Retrieved April 1, 2006, from http://www.esemag.com/0601/walkerton.html
Munger, R., & Hanson, J. W. (1997). Birth defects in Iowa: Effects of surface water pollution in the Rathbun Lake area. Retrieved April 1, 2006, from http://tango.cheec.uiowa.edu/seed/fy90/90g.html
Nadakavukaren, A. (2000). Our global environment (5th ed.). Prospect Heights, IL.: Waveland Press.
Nester, E., Anderson, D., Roberts, E., Pearsall, N., & Nester, M. (2001). Microbiology, a human perspective (3rd ed.). New York: McGraw Hill.