Env. Science: Chapter 22

Pollution from Disease-Causing Agents

(Bacteria, Viruses, Protozoans, flukes/worms) Fecal coliform monitoring-indicator of possible human waste and pathogens E coli bacteria is monitored to determine the amount of sewage present in water. E coli bacteria are only food in human and animal waste so the presence in water indicates the exposure to fecal matter. Water is filtered and the bacteria is placed on petri dishes where it will grow if present in the water. The number of colonies or spots that grow on the dish can be used as a measure of the amount present. Safe levels are determined and if the test indicates excessive amounts, investigations are started to locate the source.

Agricultural water pollution

-animal waste, pesticides, and fertilizers -Fertilizer runoff produces water enrichment and increases plant growth leading to artificial eutrophication. -Animal waste and plant residue enriches water, high BOD and suspended sediments. -Chemical pesticides that are toxic.

5 Effects of Sediment Pollution

1. reduced light penetration: suspended particles make the water turbid. Photosynthesizing organisms die and affect the rest of the food web. 2. brings insoluble toxic pollutants: sediment particles have surface area to which toxic compounds adhere, to when sediments get into water, toxins do as well 3. Sediments clog gills and feeding structures: sediment settles to form a layer over coral reefs and shellfish beds 4. potential shelters are buried: As sediments settle, they bury plant and rock shelters for smaller aquatic organisms. 5. Aquatic organisms attached to rocks are removed by the sediment washing along the bottom.

Arcata California's use of wetlands in sewage treatment

Arcata decided to use an alternative and much less expensive method to treat waste water. They created fresh water wetlands to pump in treated water. The wetlands allow the remaining pollutants to be broken down and creates habitats for large numbers of animals and plants. This system has been adopted by a number of other cities

Dead Zone

Areas like the mouth of the Mississippi River where no animals can survive because there is no oxygen available (hypoxia). Algae grow and die in such abundance that the bacteria use up all the available oxygen. Animals that can move, clear out. Those that can't are trapped and die.

BOD

Biochemical Oxygen Demand

Organic compounds

Chemical products that include carbon

Thermal Pollution

Chemical, Physical, and Biological Effects Thermal pollution occurs when water is heated during an industrial process and returned to the environment at a temperature that is higher than the normal water temperature. Higher water temperatures interfere with the waters ability to hold dissolved oxygen (DO). The higher the temperature, the less available DO for aquatic wildlife. Fish have to work harder to get to get oxygen from the water and have to eat more to keep up their energy level. There is stress on the fish that shortens their lifespan and ability to reproduce. In extreme cases, the higher temperatures can kill the fish.

Municipal Waste

Common household pollutants that can reach a river or lake or ocean or groundwater How you can make a difference around the house - alternatives, no flushing meds, protect water bodies

Eutrophication

Eutrophication is a natural process where oligotrophic bodies of water collect sediment and organic material on the bottom and gradually create marsh-like areas and new land in the form of river deltas. This is a slow process. By adding nutrients to the water, such as nitrogen and phosphorous, the plant life increases dramatically especially algae. This increases the rate of eutrophication, which is referred to as artificial or cultural eutrophication.

What happens when excess nutrients are added to a water body?

Eutrophication: aerobic bacteria increase and their respiration causes and increase in BOD....algae pop increases which means dead algae increases (decay uses oxygen) so BOD increases...DO decreases

Sewage and Fertilizer Pollution

Examples of human (artificial or cultural) eutrophication occur when high levels of nutrients and accelerate the eutrophication process so lakes and streams grow large quantities of algae which begin the process of filling in these bodies of water.

Hypoxia

Hypoxia occurs when the oxygen has been significantly reduced and can't support most living animals.

Anoxia

If there is no oxygen at all, it is referred to as anoxia, which is an oxygen-free condition.

Inorganic Chemicals

Inorganic chemicals are elements or compounds that do not include carbon. They tend to stay in the environment longer since they are not as easily broken down and collect they can collect in the environment and in the animals that ingest them. Two examples are lead and mercury

Lead (pollution)

Lead enters the environment through products that contain lead like paint and gasoline. Although both uses of lead have been banned, the past use of lead containing products has left residue in old paint and in the ground near highways where car exhaust has collected. Lead is taken into the body and collects over time. It can have a negative impact on a developing child. High levels of lead are associated with lower cognitive development.

L.U.S.T.

Leaking Underground Storage Tanks

Mercury

Mercury is an element that vaporizes at room temperature and enters the atmosphere. It is returned to earth through rain and then transformed into methyl-mercury by bacteria. Once in this form, it is ingested through the food chain and collects in the muscle tissue. In humans it can cross the blood-brain barrier and collect in the brain negatively affecting the functioning of the nervous system.

Pollution from Inorganic Plant and Animal Nutrients (Nitrates and Phosphates)

Nitrates and phosphates promote the growth of plant life in water, especially algae. Large amounts of plant life leads to dying and decaying material that is digested by bacteria. The process of breaking down organic waste is a process that requires oxygen. This process removes dissolved oxygen from the water that is no longer available to many fish. Organic matter collecting on the bottom of a body of water begins to fill in the area. Effects include: Hypoxia, Anoxia, Dead Zones, Red Tides

Oligotrophic vs Eutrophic

Oligotrophic bodies of water include lakes, estuaries and slow moving streams that have low levels of nutrients and are considered unenriched or oligotrophic. The water is clear and cold at deeper levels. It supports small groups of aquatic organisms. Eutrophic bodies of water have higher levels of nutrients and support more aquatic life. The water is cloudy and warmer. This water is nutrient enriched and leads to the growth of algae and bacteria. When to algae dies, it sinks to the bottom and is decomposed by the bacteria. The decomposition process requires oxygen which decreases the DO available for fish.

Pollution from Organic compounds (pesticides and oils)

Organic compounds are chemical products that include carbon. They can be naturally occurring like sugar or petroleum, or artificial compounds like plastics or pesticides. Some toxic organic compounds go right into the water from landfills and runoff and some leech through the soil and contaminate groundwater.

Industrial Wastes

Paper pulp and Food Industries - raise the BOD, -Electrical Industries - release heavy metals

Point vs Nonpoint Pollution

Point pollution comes from a specific location usually through pipes, sewers or ditches from industrial sites or sewage treatment facilities. Since the location can be isolated and the source identified, point pollution is easier to address legislatively. There is still the problem that comes with accidental spills and clean ups. Nonpoint pollution enters water from larger areas and a variety of sources. Major sources include agricultural run-off, municipal (city) wastes and industrial wastes. Because of the diverse sources of pollution and variety of places where pollution can enter the water system, nonpoint pollution is a greater challenge to prevent.

Sustainable water use

Providing enough clean water for the future includes waste water treatment so that water can be used over and over for a variety of purposes, essentially recycling water.

Sediment Pollution

Sediment pollution occurs when there are large amounts of soil particles suspended in water that settle out and cover the bottom of a body of water. The source of sediment comes from erosion due to farming land, clear cutting forests, over grazed land, degrading river banks, strip mining and construction. Problems with sediment include, clouding the water (turbitity) which reduces light penetration and decreases photosynthesis, covering animals so that they can't take in nutrients. The sediment scrapes away any living thing that is resting or attached to rocks. Sediment can also carry toxic substances. Finally, sediment pollution can clog waterways.

Groundwater Pollution (Sources and Effects)

Sources: Leaking Underground Storage Tanks (L.U.S.T.), fertilizers, pesticides, leaking landfills Effects: blue babies from excess Nitrogen in drinking water, contaminated drinking water

CSO's (Combined Sewer Overflows)

Storm drains connected to sewer pipes Overflow in high rain event, water overflows into the water system without treatment - -Providence's "Big Dig" to prevent this from happening

Endocrine Disrupters- Hormone Mimics

Surveys of water content shows small, but significant levels of organic compounds that include drugs, which can disrupt the function of hormones in animals by mimicking the structure of the hormones or blocking the hormones from biological processes

Radioactive Substances

Unstable isotopes that emit high energy particles as they break apart. These high energy particles can break down biological substances and effect the reproduction of cells, which can lead to cancer or genetic mutations. Radioactive materials are used in a variety of processes including generating electricity, producing weapons and medical treatments. Radioactive material can be released into the environmental and end up in the water systems. It can often be found in the sludge that is left over after treating water. Radioactive material can stay radioactive for a long period, so it is difficult to dispose of safely.

Red Tide

certain algal bloom can turn the water orangey-brown (red coloring). In the blooming process they also create toxins that poison animals directly and indirectly when the poison animals are eaten

Green Chemistry

using chemicals that break down more quickly or using alternatives that have less negative impact