unit 8

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Landfills

cap them, plant trees/plants to restore habitats and green spaces AND capture CO2 and methane gas to generate electricity

true or false Most US waste sent to landfills, waste can leach out and contaminate groundwater and also produces ghg CO2 and methane

true

Anthropogenic sources of eutrophication

waste treatment facilities, fertilizers/pesticides from housing/farms/feedlots/golf courses/lawns, sewage and drainage overflows, household phosphate products

Evaluate dose response curves.

A dose response curve describes the effect on an organism or mortality rate in a population based on the dose of a particular toxin or drug.

Identify differences between point and nonpoint sources of pollution.

A point source refers to a single, identifiable source of a pollutant, such as a smokestack or waste discharge pipe. Nonpoint sources of pollution are diffused and can therefore be difficult to identify, such as pesticide spraying or urban runoff.

Fourth stage

ADVANCED TREATMENT - used to eliminate micropollutants that may not be eliminated by previous treatments including pharmaceuticals, chemicals, and pesticides using many methods including use of fungi, activated carbon filters, ozone, and enzymes

Secondary treatment

BIOLOGICAL TREATMENT - Only liquid waste goes into this stage, bacteria is aerated to speed up decomposition into CO2 gas and inorganic sludge which sinks to bottom of tank 1. The primary effluent goes into the aeration tank which is supplied with air using a compressor which is then pumped into a secondary clarifier, the remaining secondary effluent goes into 3 treatment 2. The inorganic sludge left in bottom of secondary clarifier are resent into the aeration tank for further processing and disposed of and released

Dissolved oxygen (DO)

Bacteria decaying organic matter use oxygen and create eutrophication, often in summer bc warmer water has less DO than cold, too low DO indicates possible water pollution and shows potential for further pollution downstream

Eutrophication

excess of nutrients ( N, P) from land runoff that the nutrients "fertilize" the aquatic organisms that live there and effects include: a.Reduces light penetration for algae b. changes species composition/dominance/balance c. decreased biodiversity d. Releases toxic gases during decomposition (methane, H2S) e. Large fish kills due to low DO f. Algal blooms increase g. Thick and turbid water h. Increased algal biomass i. Toxic phytoplankton can release neurotoxins to kill aquatic organisms

Clean Water Act (1972)

federal law that insures clean water for sports/recreation, prohibits release of highly toxic substances, prohibits point source pollution, regulates discharge into wetlands, and restores/maintains integrity of national water supply

Safe Drinking Water Act (1974)

federal law to ensure drinking water supply that doesn't apply to private wells, requires EPA to set universal drinking water standards, and sets max levels for microorganisms/chemicals/disinfectants/radionuclides

E-waste

(computers, TV, electronics) can be recycled, prevents mining and dump in landfills Problems Air pollution by burning plastics Groundwater contamination Health issues due to exposure to heavy metals Surface runoff containing heavy metals It is being exported to other countries so NIMBY Solutions I. adopting laws that outlaw exporting wastes to developing countries 2. Provide tax incentives to companies that allow trade in allowances for consumers that have older models 3. Require disposal tax on products

Composting

(food, paper, and yard waste) put into piles, allowed to decompose, and use for fertilizer (organic)

Fecal coliform

(intestinal bacteria form concentrations E. coli example) Indicates untreated sewage dumping from farms and animal feedlot runoff

Turbidity

(measure of how light is scattered in the water column due to solids that don't dissolve but are small enough to be suspended in water) More turbidity = cloudier water Reduces light penetration Reduces photosynthetic activity Holds more heat increasing temp and lowering DO Suspended solids can clog fish gills and settle to bottom to kill eggs/larvae and bury nesting sites Sources include soil erosion, dredging, increased water flow rates say downstream of a dam

reuse

(use again in different way) 1. A - reduce landfill impact, glass refillable up to 15 times, industry machinery in place already, most efficient way to reclaim materials 2. D - economical only when item is expensive and labor is cheap, collecting materials is expensive, cleaning and decontaminating expensive

Water quality tests

-Chemical, physical, and biological characteristics of water -Measures the condition of the water relative to the requirements of one or more biotic species or any human need/purpose -Compared to a set of standards to assess compliance and protect ecosystem health, human contact with water, and drinking water quality -Can also be used to evaluate -Ability of body of water to support aquatic life in an ecosystem -Characteristics of a water source before treatment for drinking water -Characteristics of polluted water before or after treatment -Suitability of water for industrial uses (cooling, manufacturing, lab work) -Water treatment process effectiveness

Direct factors include Pollution and Human health

-Dysentery - untreated sewage in streams and rivers that have become drinking water or food contaminants which results in intestinal infection with symptoms of diarrhea, blood and mucus in feces, more common in developing countries -Mesothelioma - exposure to asbestos (fibrous building material that was flame resistant used in insulation, flooring, piping, ceiling and as they broke down were released as particulates in air) and caused lung cancer Asthma, emphysema, COPD - exposure to tropospheric ozone and particulates created from sunlight, NOx, and VOCs reacting in the presence of sunlight

Describe the effects of solid waste disposal methods.

-Factors in landfill decomposition include the composition of the trash and conditions needed for microbial decomposition of the waste. -Solid waste can also be disposed of through incineration, where waste is burned at high temperatures. This method significantly reduces the volume of solid waste but releases air pollutants. -Some items are not accepted in sanitary landfills and may be disposed of illegally, leading to environmental problems. One example is used rubber tires, which when left in piles can become breeding grounds for mosquitoes that can spread disease. -Some countries dispose of their waste by dumping it in the ocean. This practice, along with other sources of plastic, has led to large floating islands of trash in the oceans. Additionally, wildlife can become entangled in the waste, as well as ingest it.

pros of sanitary municipal landfills

-Geologic or environmental impact studies performed prior to determine safety -Liners, drainage systems control leaching of contaminants into groundwater -Methane collection can be used to generate electricity -Waste is covered daily to prevent insects and rodents

Identify sources of human health issues that are linked to pollution.

-It can be difficult to establish a cause and effect between pollutants and human health issues because humans experience exposure to a variety of chemicals and pollutants. -Dysentery is caused by untreated sewage in streams and rivers. -Mesothelioma is a type of cancer caused mainly by exposure to asbestos. -Respiratory problems and overall lung function can be impacted by elevated levels of tropospheric ozone.

Define lethal dose 50% (LD50).

-Lethal dose 50% is the dose of a chemical that is lethal to 50% of the population of a particular species. -amount of toxin (grams or milligrams of substance per kilogram of body mass, ppm in air, or mass/volume in water/blood) that kills 50% of the organisms being tested after a specified time 1.Helps to determine the relative short-term toxicity of a chemical (lower LD50 means greater toxicity) 2.Can be shown by a dose response curve if y axis is percent/amount dead/mortality rate 3.Limitations are that there is great variability between species (lethal to one, not to another)

Steps in cultural(anthropogenic) eutrophication:

-Nutrients (N,P) from agriculture(fertilizers,animal waste), residential(detergents), urban (fossil fuel combustion) runoff into waterway -Algae grow faster creating algal bloom -Sunlight doesn't penetrate and carrying capacity exceeded so algae and plants die -Dead plants and algae are decomposed by bacteria and fungus that are carrying out cellular respiration and depleting oxygen faster than it can be produced bc no more photosynthesis happening -Dissolved oxygen decreases so dead zone for fish and aquatic life usually at or near bottoms of inhabited coastlines where aquatic life more concentrated (Northern Gulf of Mexico which is outfall for Mississippi River & Chesapeake Bay & Coasts of Pacific NW (Ca, Or, Canada)

Persistent Organic Pollutants (POPs)

-POPs do not easily break down in the environment because they are synthetic, carbon-based molecules (such as DDT or PCBs). -POPs can be toxic to organisms because they are soluble in fat, which allows them to accumulate in organisms' fatty tissues. -POPs can travel over long distances via wind and water before being redeposited. Take a long time to break down (persistent) and can travel in wind and water very far distances Bioaccumulate and biomagnify in mostly fatty animal tissue and increase in their toxicity as it goes up the food chain/web trophic levels

Describe changes to current practices that could reduce the amount of generated waste and their associated benefits and drawbacks.

-Recycling is a process by which certain solid waste materials are processed and converted into new products. -Recycling is one way to reduce the current global demand on minerals, but this process is energy-intensive and can be costly. -Composting is the process of organic matter such as food scraps, paper, and yard waste decomposing. The product of this decomposition can be used as fertilizer. Drawbacks to composting include odor and rodents. -E-waste can be reduced by recycling and reuse. E-wastes may contain hazardous chemicals, including heavy metals such as lead and mercury, which can leach from landfills into groundwater if they are not disposed of properly. -Landfill mitigation strategies range from burning waste for energy to restoring habitat on former landfills for use as parks. -The combustion of gases produced from decomposition of organic material in landfills can be used to turn turbines and generate electricity. This process reduces landfill volume.

thermal pollution

-Source is nuclear or other power plants, no chemicals dumped just heated water. Global warming is adding additional heat to oceans, rivers, and streams. -Problem is that warm water has lower levels of dissolved oxygen than cold water, it diffuses into the air instead of the water -Low dissolved oxygen levels as well as higher temperatures are usually outside of aquatic organism range of tolerance and decreases population sizes. Small organisms more adversely affected and they are base of food chains/webs.

Endorcrine disruptors

-The effects include chemicals bioaccumulating in aquatic organisms, altering genders for frogs and fish, and disruption of reproduction and growth of organisms. -They cause these effects by mimicking or block the receptors of hormones and can cause birth defects in the nervous/immune/reproductive systems and the development of organisms and cause infertility. -Examples of these chemicals include: BPAs (plastics), dioxin (byproduct of herbicide production, paper bleaching, and waste incineration), phthalates (packaging, plastics, toys,and medical devices), PBDE (flame retardant), and PCBs (electrical equipment, hydraulic fluids, and heat transfer fluids)

Describe the effects of thermal pollution on aquatic ecosystems.

-Thermal pollution occurs when heat released into the water produces negative effects to the organisms in that ecosystem. -Variations in water temperature affect the concentration of dissolved oxygen because warm water does not contain as much oxygen as cold water.

Describe the impact of human activity on wetlands and mangroves.

-Wetlands are areas where water covers the soil, either part or all of the time. -Wetlands provide a variety of ecological services, including water purification, flood protection, water filtration, and habitat. -Threats to wetlands and mangroves include commercial development, dam construction, overfishing, and pollutants from agriculture and industrial waste.

12 key POPs determined to be reduced or eliminated by 2001 Stockholm Convention and enforced in 2004

1 DDT (insecticide) 2 PCBs (coolant fluids in electrical equipment) Ten others: Pesticides - DDT, Aldrin, Chlordane, Dieldrin, Endrin, HCB, Heptaclor, Mirex, Toxaphene Industrial Chemicals - PCB, HCB Unintentionally Produced Byproducts - Dioxins, PCBs, Furans, HCB

Water treatment methods

1. Absorption - one substance completely enters another (paper towel spill cleaning) 2. Adsorption - one substance attaches to the other (contaminants sticking to charcoal) 3. Disinfection - using chemicals to kill or prevent growth of pathogenic organisms (chlorine, ozone, UV light) 4. Filtration - removes clays, organic matter, precipitants, and silts in order to clarify water to enhance disinfection 5. Floculation sedimentation - combining small particles into larger particles then settle out as sediment 6. Ion exchange - removes inorganic constituents (arsenic, chromium, fluoride, nitrates, radium, uranium)

Difficult to assign particular pollutants to human health issues because of a variety of factors but can be

1. Carcinogenic - cause cancer (asbestos, radiation exposure, radon, UV rays, tobacco smoke) 2. Neurotoxins - cause damage to nervous system (Lead, Mercury, pesticides) 3. Teratogens - can cause birth defects (Alcohol, tobacco, radioactive compounds, Mercury, Lead, PCBs) 4. Allergens - cause allergic reactions (mold, smoke) 5. Endocrine disruptors - cause damage to endocrine system/hormones (BPA, dioxin, phthalates)

Tertiary treatment

CHEMICAL TREATMENT - chemicals (ozone gas or chlorine(most common) or UV light) kill remaining bacteria, water is then released 1. The secondary effluent is disinfected with chlorine, ozone, UV light, or physically through lagoons/microfiltration then put into 4th treatment or discharged 2. Phosphorus is removed through coagulation using lime 3. Nitrates are removed often by alcohols/sugars/denitrifying bacteria

Describe endocrine disruptors.

Endocrine disruptors are chemicals that can interfere with the endocrine system of animals.

Describe the impacts of human activities on aquatic ecosystems.

Organisms have a range of tolerance for various pollutants. Organisms have an optimum range for each factor where they can maintain homeostasis. Outside this range, organisms may experience physiological stress, limited growth, reduced reproduction, and in extreme cases, death. ex:Coral reefs have been suffering damage due to a variety of factors, including increasing ocean temperature, sediment runoff, and destructive fishing practices. ex:Oil spills in marine waters cause organisms to die from the hydrocarbons in oil. Oil that floats on the surface of water can coat the feathers of birds and fur of marine mammals. Some components of oil sink to the ocean floor, killing some bottom-dwelling organisms.

Primary treatment

PHYSICAL SEPARATION - sewage is filtered with grates and screens for large solid non-liquid items and grit chambers used to slow down flow so eggshells and coffee grounds that don't sink can go to a landfill 1. Screens, Comminutor (tumbler), Grit chamber,and grit disposal separate into layers 2. The layered mix goes into the primary clarifier and the effluent (liquid) goes into 2 treatment while the raw/primary sludge is released

cons of municipal landfills

Plastics take a long time and may never decompose 2. Methane, a GHG, is released 3. NIMBY 4. Areas for landfills are limited and expensive 5. High cost of running and monitoring landfill 6. Transportation costs to and from landfills

Describe best practices in sewage treatment.

Primary treatment of sewage is the physical removal of large objects, often through the use of screens and grates, followed by the settling of solid waste in the bottom of a tank. Secondary treatment is a biological process in which bacteria break down organic matter into carbon dioxide and inorganic sludge, which settles in the bottom of a tank. The tank is aerated to increase the rate at which the bacteria break down the organic matter. Tertiary treatment is the use of ecological or chemical processes to remove any pollutants left in the water after primary and secondary treatment. Prior to discharge, the treated water is exposed to one or more disinfectants (usually, chlorine, ozone, or UV light) to kill bacteria.

recycle

Recycling (treating or processing waste materials to make them suitable for reuse) 1. Closed loop ( waste or byproduct of one process/product used to make another - recycling waste newspaper to other types paper) OR Open Loop (conversion into a new product, involving a change in properties of material usually from low quality to higher quality - using recycled plastic bottles to make rigid plastic drainage pipes) 2. A - provide economic incentives, reduce air/water pollution, reduce landfill impact, reduces energy requirements to produce products, reduces need for raw materials, reduces dependence on foreign oil for plastic production, turns waste into a resource, remanufacturing (using recycled products) 3. D - poor regulation, could be unprofitable, single use plastic more convenient, toxins may be present in materials

What are the three R's

Reduce, reuse, recycle in that order

Describe solid waste disposal methods.

Solid waste is any discarded material that is not a liquid or gas. It is generated in domestic, industrial, business, and agricultural sectors. -Solid waste is most often disposed of in landfills. Landfills can contaminate groundwater and release harmful gases. -Electronic waste, or e-waste, is composed of discarded electronic devices including televisions, cell phones, and computers. -A sanitary municipal landfill consists of a bottom liner (plastic or clay), a storm water collection system, a leachate collection system, a cap, and a methane collection system.

Describe the effects of bioaccumulation and biomagnification.

Some effects that can occur in an ecosystem when a persistent substance is biomagnified in a food chain include eggshell thinning and developmental deformities in top carnivores of the higher trophic levels. -Humans also experience harmful effects from biomagnification, including issues with the reproductive, nervous, and circulatory systems. -DDT, mercury, and PCBs are substances that bioaccumulate and have significant environmental impacts.

sources of endocrine disruptors

Sources of endocrine disruptors include drug prescriptions both for human(90% pass through unaltered) and farm animals, personal care products, pesticides, foods (milk from cows where GH was given), and household products that pass into local waterways as treatment plants can't filter the endocrine disrupting chemicals out.

Solutions/Reduction of eutrophication:

a. Control feedlot runoff of waste/pollutants b. Control timing and amount of fertilizers c. construct wastewater lagoons/retention ponds near agricultural areas d. Plant vegetation buffer zones along streambeds to control erosion and absorb excess nutrients e. Install permeable pavement and legislate that transition to absorb urban runoff f. Upgrade water waste treatment plants to control N and P runoff g. Use incentives to convert inefficient irrigation systems to drip systems h. Incentives to replace landscaping with native vegetation that needs less water and less fertilizer

BOD (Biological Oxygen Demand)

approximates level of biodegradable waste in water including vegetation, animal wastes, and sewage) Higher BOD means low DO and high bacteria count

Dose response relationships

changes or effects on an organism with differing levels of drug or chemical over periods of time both at individual or population level, can help to determine safe and hazardous dosages as well as potential pollutants and is used to determine public policy/laws a. Acute effects - rapid, severe, sudden exposure to usually a single large concentration with accurate diagnostics and quick treatment available b. Chronic effects - prolonged, repeated exposure over time with symptoms not immediate but often irreversible (cigarette smoking, asbestos exposure)

Sanitary municipal landfills

control disposal of solid waste -Clay and plastic lining to prevent leaks at bottom and layers of soil/clay/sand seal in trash when full -A leachate pump to collect liquid passed through trash (wells and probes monitor these) with a storage tank for safe disposal or storage before use -Pipes to collect methane gas during decomposition in order to burn off or generate electricity -Ways to generate excess stormwater so it doesn't infiltrate landfills

ED50

dose at which 50% of population has a non-lethal effect from the substance (cancer, infertility, paralysis)

Bioaccumulation

increase in the concentration of a pollutant within an organism because chemicals that build up in the fatty tissues of animals because they don't break down(they are persistent). It is dependent upon the following factors: Mode of uptake (in food, through gills, contact with skin) Degree of fat solubility of the pollutant Rate at which substance is eliminated from the organism Transformation of substance by animal metabolism Fat content of the organism (bony fish vs fatty fish)

Biomagnification

increasing concentration of a substance in the tissues of organisms at successively higher trophic levels within a food chain because when animals eat other animals in a food chain or web, the chemicals magnify as they move up the food chain/web (so higher trophic levels have higher chemical levels - sharks have more than fish they eat) because top predators eat many different prey and at higher numbers to maintain their body size. In order for biomagnification to occur the pollutant: Must be long lived Must be mobile Soluble in fats because if water soluble it will be excreted (mammal milk high in fat so good indicator level and young are more susceptible to toxins) Must be biologically active (adverse effects in small doses)

Nonpoint

multiple sources, often farm runoff/CAFOs, difficult to mitigate (urban runoff, agricultural runoff, roads)

Point source

one single identifiable source, easier to treat (factories, sewage plants)

DRC

shows the relationship between dose of a drug and its pharmaceutical effect -Dose(independent variable) - concentration of of chemical added to water, food, or air is on x axis, effect(dependent variable) - response measured in organism, usually death or impairment is on y axis -Shaped like letter S because small doses not toxic but as dose increases there is a greater response -Helps determine causality (link between chemical and effects), toxicity threshold (point in curve where where effect occurs first occurs-lowest dose), and slope (rate at which effect builds up) -Individuals have different tolerance levels and this is accounted for by using large sample sizes -A curve with a steep slope/greater slope and low number indicates high potency/toxicity


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