Can anyone give me matter on the effects of toxic substances on aquatic life.?

Question

i need it immeadiately!!!!!!!!!!!!

Answer 1

Water quality by definition is how polluted it is depending on what it is used for. Water quality depends on the amount of contaminants in the water; the quality is higher if there are less contaminants. There are different standards and regulations for different conditions. The requirements for drinking water are the strictest. There are also separate standards for swimming in the water, or eating the fish or plants from the water. These standards are much less strict compared to drinking water quality. The Safe Drinking Water Act was passed in 1974 and ensures the safety of tap water. The Environmental Protection Agency had set standards for the drinking water. The Class B water standards are used as standards in maintaining the wildlife habitat.
The EPA has developed a maximum contaminant level goal (MCLG) and a maximum contarninant level (MCL) for all regulated contaminants for drinking water. Water that meets the MCLG would not cause any health problems in a lifetime. The MCL is the contaminant standards that are actually enforced. It is as close to the MCLG as possible while staying within the financial and technical boundaries. There is a long list of contaminants the government test for in the water. They are divided into four groups: microbial pathogens, organics, inorganics, and radioactive elements.
Microbial pathogens include parasites, viruses, and bacteria. Fecal coliform is the most commonly tested pathogen. These pathogens get into the water due to sewage and animal wastes. They can cause gastroenteritis, salmonella infection, dysentery, shigellosis, hepatitis, and giardiasis (a gastrointestinal infection causing diarrhea, abdominal cramps, and gas). The pathogens cannot exceed 200 in a 100 ml sample in order for wildlife to survive.
Organics including Trihalomthanes (THMs), are formed when remains of the chlorine used to disinfect the water combines with other organic substances. They also come from pesticides, including herbicides, insecticides, and fungicides; and volatile organic chemicals (VOCs), which include solvents, degreasers, adhesives, gasoline additives, and fuels additives. Some of the common VOCs are: benzene, trichloroethylene (TCE), styrene, toluene, and vinyl chloride. Possible chronic health effects include cancer, central nervous system disorders, liver and kidney damage, reproductive disorders, and birth defects. These are not to exceed 0.5 mg/L in drinking water.
Inorganics include metals, and metalloid positive and negative ions. Such are arsenic, mercury, silver, barium, lead, chromium, and nitrates. These come from the plumbing pipes, natural sources, and industrial wastes. Metals are aluminum, sodium, potassium, and zinc. Positive ions include arsenic, lead, mercury, and copper. Calcium and magnesium are found as both metals and positive ions. Mercury, lead, and arsenic are very dangerous. The other ions are good in the right amounts although may be undesirable because they are the reason for hard water. Negative ions are fluoride, chloride, nitrate, nitrite, phosphate, sulfate, carbonate, and cyanide. Just like positive ions, small amounts of chloride and carbonate are essential to life. Nitrates and nitrites are moderately harmful, while cyanide is lethal even in small amounts. Fluoride can lessen tooth decay but can become dangerous if overdosed. All of these combined cannot exceed 600 ml/L for drinking water. The pH level also falls in this category. For drinking water, it must be 6.5 to 8.5. For swimming and supporting wildlife, it must be 6.5 to 9.0.
Radon is a radioactive element and comes from decayed uranium from rocks and soil. This may occur because the water is contained in a bed rock. A long exposure to these pollutants my result in serious health problems such as cancer, liver and kidney damage, damage to the immune system and nervous system, and birth defects. This factor is especially dangerous because radioactivity is so harmful to living organisms.
There are other factors tested for water in wildlife and for swimming that are not tested for in drinking water. These are turbidity, temperature, water flow, and dissolved oxygen (DO). The turbidity is the clearness of the water. If it exceeds 10 NTU then other impurities are present in the water. It is also important because if the water is too murky, it would block the passage of sunlight, which is important for photosynthesis of the water plants. It may be undesirable to swim in water with high turbidity since it may leave some waste and staining on the skin. Temperature should not go over 83°F and not vary over 5°F due to a discharge. It is important that the temperatures is not exceedingly hot nor vary too much for the well being of the fish and other wildlife in the water, and also that one would be willing to swim in it.
DO is not important for the swimmer but is an essential part of wildlife. All the organisms in the water depend on this source of oxygen to perform cellular respiration. The DO must not be less then 5.0 mg/L. Water flow is the rate that the water travels from one to the other. It is important for the exchange of the material in the water. If the water flow is too slow or too fast, it would have a high turbidity since the materials would be rarely exchanged and there would be a buildup or exchanged too often that the materials do not have enough time to settle down. Water flow, turbidity, temperature, and DO are all interconnected. The more turbid the water is, the more heat it would absorb. As the water heats up, the level of DO decreases, because everything speeds up and the organisms use up the DO faster. Therefore, all of these factors are all extremely important, and if one goes astray, everything else will collapse, too.
There are many tests that can be performed to detect the contaminants in the water. Coliform bacteria test show the existence of microorganisms that are harmful to humans. Sodium, chloride, sulphate, iron, and manganese adds odor to the water. There are the Inorganic Chemistry Analysis and the Bacteriological Analysis. The water must be collected in sterile bottles and capped immediately. The bottles should be refrigerated until ready to be tested. When testing, the samples cannot be kept in the bottles for over 24 hours. 100 ml of the water is poured into a filtering funnel, which would capture any sediment from the water. The filter is then put into a Petri dish containing agar to stimulate any bacteria growth. It is left at 35 C for 24 hours. E. coli appears as blue circles, and coliform is pink; each circle represents a colony. If there are over 200, then there might be threat to human health.
Spring is the best time to test for nitrates. The standard is 45 milligrams per liter if the results are reported as nitrate (NO3). Phosphates stimulate the growth of algae and can be tested by a phosphate test. A reading of 1.0 ppm or less is considered excellent. A phosphate level between 1.1-4 ppm is good. A level between 4.1-9.9 ppm is fair, and a level greater than 10 ppm is poor. The cyanide is tested by converting it to volatile hydrogen cyanide, which permeates through a PTFE membrane, reaching colorimetric reagents and then compared against the color scales. Less than 10 ng of free cyanide per ml can be easily detected. For more concentrated solutions, the results had been compared to those obtained using differential pulse polarography. The standard addition method can be used for more diluted solutions.
The test for pH is very simple. First, a sample of the water must be attained and put into the collection bottle from a pH testing kit. Then, the color strip must be put into the sample and allowed to fully change its color. When it is done, the strip is to be taken out and compared to the color chart provided with the kit. Each color would correspond to a certain number on the scale. A reading of 7.0 is neutral, while anything below 4.0 is acidic, and anything above 10.0 is basic.
To test for DO, one must use a DO testing kit. A sample of the water must be collected in the bottle provided with the kit. It must be filled completely and capped while the bottle is still submerged in the water, ensuring that no air bubbles would enter. Then, the cap must be removed quickly and a packet of DO reagents added into the sample. The bottle must be recapped immediately and then shaken. The water would then turn to another color depending on the level of DO. Follow the chart provided with the packet to find out what each color means.


http://www.gov.pe.ca/photos/original/watertest.pdf

http://www.cyber-nook.com/water/index.html

http://www.healthywater.org/testingkits.html

http://www.dem.ri.gov/programs/benviron/water/quality

http://www.epa.gov/waterscience/standards

http://www.bae.ncsu.edu/programs/extension/publicat/wqwm/he393.html

Answer 2

Here are a number of sites that may be helpful to you. Best of luck with it.

Answer 3

why dont you just do your own homework?? =)