The flashcards below were created by user
on FreezingBlue Flashcards.
What is Atrazine?
- -Widely used in gerbicides
- •Effective and inexpensive-Contamination of drinking water
- •Birth defects
- •Low sperm count
- •Possible carcinogenic–Banned in Europe, but still widely used in the world
- •EPA – currently insufficient data
What is Bisphenol A (BPA)?
- •Bisphenol A (BPA)
- –Used in plastics
- –Internal coating of metal food and beverage cans
- –Mimics estrogen–Endocrine hormone disruptor
- •Mammary and prostate cancer, genital defects in males, early onset of puberty in females, ADHD–FDA (2010) warned of possible hazards to fetuses, infants and young children
- •Banned in Japan, Canada, and most European countries
- •US banned use in baby bottles – Still debating overall use–Detoxified in the adult liver (children’s liver not as well developed)
- •Secondary sexual development changes, brain and behavioral changes and immune disorders
What is Polychlorinated Biphenyl (PCB)?
- •Polychlorinated Biphenyl (PCB)
- –Endocrine hormone disruptor
- –Used as a coolant and insulating fluid in transformers and electric motors
- •Also used in paint, cement, fire retardant fabric, adhesives, water-proofing–99% produced by the Monsanto Company from 1930-1977
- –Recognized as a persistent organic pollutant
- –Banned by Congress in 1979
- –Shown to cause cancer
A state of complete physical, mental, and social well-being.
An abnormal change in the body's condition that impairs physical or psychological function.
Define Morbidity & Morality
Roles of Morbidity & Morality
Diet and nutrition, infectious agents, toxic chemicals, genetics, trauma and psychological stress
What is Global Disease Burden?
- -Diabetes is on the increase.
- -Global disease burden from 10% currently to 15%
- •Communicable diseases are still responsible for about 1/3 of all disease-related deaths.-Majority in countries with poor nutrition, sanitation, and vaccination
- •New diseases test our defenses in developed countries.v1350 – Bubonic black from Asia killed half Europe’s populationvEarly 1500’s
- – European explores to North America killed 90% of Native American population (smallpox, measles, cholera, yellow fever)
- •Better nutrition, clean water, improved sanitation and inoculation of children could eliminate most of the deaths.
- •76 million cases of food borne illness in US with 300,000 hospitalizations and 5,000 deaths
- •2010 – 6 million pounds of beef recalled – E.coli
What is Emergent Disease?
- -One never known before, or one which has been absent for at least 20 years.
- -Air travel makes it possible to spread emergent diseases around the globe quickly.
- EXXX: Bird Flu, Ebola fever, HIV
What is Ecological Diseases?
- •Ecological diseases - animal epidemics
- -White nose syndrome in bats due to a fungus recently introduced into the eastern US from Europe
- -Rouse to frequently from torpor and starve-California sea lions have herpes 1 virus spread to them from human sewage.
- -Dermo (degrades tissue), a parasite of oysters, is spreading rapidly along the east coast due to climate warming.
What is Conservation medicine?
Examines how enviromental changes threaten the health of human and natural communities.
What is Antibiotic Resistance?
- -Antibiotics: Chemicals that kill the growth of bacteria
- •At least half of the 100 million antibiotic doses prescribed in the U.S. every year are unnecessary or are the wrong drug.
What is Toxicology?
- -The study of poisons and their effects on living systems.
- -Divided up into two broad categories: Toxic & Hazards.
Deals with the interactions, transformation, fate, and effects of natural and synthetic chemicals in the biosphere.
- Known poisons thst damage or kill cells/ tissues
- -Can be general or very specific. Often harmful even in dilute concentrations.
- Dangerous but not toxic.
- -Flammable, explosive, irritant, acid, caustic.
What are Toxins?
- -Immune System Depressants
- -Endocrine Disrupters
- *Enviromental estrogens-enviromental contaminants (e.g. BPA, dioxins) which cause reproductive problems in animals even at very low doses*
Define Immune System Depressants & Endocrine Disrupters:
- •Immune System Depressants - pollutants that depress the immune system
- •Endocrine Disrupters - disrupt normal hormone functions
- •Neurotoxins - metabolic poisons that specifically attack nerve cells; most are extremely toxic and fast acting.
- EXXX: Heavy Metals:Kill nerve Cells, Anesthetics and Chlorinated Hydrocarbons: disrupt nerve cell membrane, Organophosphates and Carbamates:inhibit signal transmission between nerve cells.
Define Mutagens & Carcinogens:
- Mutagens: Agents that damage or alter genetic material. Can lead to birth defects or tumors.
- Carcinogens: substances that cause cancer
- *Cancer is the 2nd leading cause of death.
- *1 in 2 males and 1 in 3 females in the U.S. will have cancer in their lifetime.
- •Teratogens: specifically cause abnormalities during embryonic growth and development
- *Alcohol - Fetal Alcohol Syndrome
- *Developmental delays, behavior problems, mental defectsv300,000-600,000 children born every year exposed to unsafe levels of mercury
One of most important characteristics in determiningthe movement of a toxin.
- •Chemicals are divided into two major groups:
- *Those that dissolve more readily in water
- -Move rapidly through the environment and have ready access to cells via tissue fluid.
- *Those that dissolve more readily in oil
- -Need a carrier to move through the environment. Once inside the body they penetrate tissues easily and cross cell membranes. Stored in body fat and persist for many years.
- •Bioaccumulation: selective absorption and storage of toxins
- *Dilute toxins in the environment can build to dangerous levels inside tissues.
•Biomagnification: Toxic burden of a large number of organisms at a lower trophic level is accumulated and concentrated by a predator at a higher trophic level. Example: DDT, mercury
What are the types of Chemical Interactions?
- Antagonistic Reaction: which stimulates the breakdown
- Additive Reaction: which effects of 2 chemical occuring together are added to 1 another
- Synergistic Reaction: 1 substance exacerbates the effect of the other
What 3 principal factors control global water deficits and surpluses?
- *Global atmosphere circulation
- *Proximity to water sources
Define Residence Time:
The length of time water typically spends in a compartment.
Water that resides under the surface of the earth within the zone of saturation. It occurs within soil, bedrock, or in caves.
**The 2nd largest reservoir of fresh water**
An open space in soil or rock
- Total volume of rock that consist of pore space.
- *Primary: Original open pore space in soil or rock after it forms.
- *Secondary: Open space that forms after soil or rock is created.
The ability of a material (such as rock or soil) to allow flow (ie. Groundwater) to flow through it (hydraulic conductivity)
Define Permeable & Impermeable:
Peremeable: Material that has interconnected pore space which allows water to flow through it.
Impermeable: Material that does not have interconnected pore space, thus not allowing water to flow through it.
Define Infiltration & Zone of Aeration:
Infiltration: Process of water percolating through the soil and into fractures and permeable rocks.
Zone of Aertion: Zone above watertable where infiltration occurs.
Define Watertable & Zone os Saturation:
Watertable: boundary that separates fully saturated soil and rock from partially saturated soil and rock under the surface of the earth.
Zone of Saturation: Zone where the pore space is filled with groundwater.
•Rock and/or sediment that is saturated with groundwater, and is sufficiently permeable to allow economically viable quantities of groundwater to wells and springs
Define Confined Aquifer & Potentiometric surface:
- Confined Aquifer: saturated groundwater that is enclosed by impermeable layers both below and above it. Artesian wells are an example.
- Potentiometric surface: is the elevation that confined groundwater would rise, due to pressure, but it is not allowed because of aquicludes.
The amount of water that passes a fixed point in a given amount of time.
Define Water Stress:
•occurs when human and ecosystem needs exceed the renewable water supplies, resulting in competition.
Define Water Withdraw & Consumption:
- Withdraw: Total amount of water removed from a water body.
- Consumption: Loss of water due to evaporation, absorption or contamination.
What is Groundwater Mining?
- •Groundwater is the source of nearly 40% of fresh water in the U.S.
- •50% of Americans (95% in rural areas) depend on groundwater for drinking and domestic uses.
- •In many places in the U.S., groundwater is being withdrawn faster than it is replenished.
- •Heavy pumping can deplete entire aquifers.
What is Miami Valley Aquifer?
- •“Buried Valley” Aquifer System
- -Ancient river valley filled with sand, gravel, and other glacially-transported sediments.
- •Pre 1970s:Drawdown of aquifer by manufacturers and utilities
- -Extensive development in low-lying areas
- •Post 1970s:Disappearance of manufacturing and change in utilities = Less drawdown
- -Aquifer level rose to earlier levels
- -Flooding in basements and lower-level areas of many homes and facilities in low-lying areas
What is saltwater intrusion?
can occur along coastlines where oversue of freshwater reservoirs draws the water table low enough to allow saltwater to intrude.
What is Land Subsidence?
•Withdrawing large amounts of groundwater in a small area causes porous formations to collapse, resulting in subsidence (settling).
What is a Dam?
- •Before 1900 there were 250 high dams in the world, today there are more than 50,000; 90% were built in the twentieth century.
- •Dams-Provide inexpensive hydroelectric power
- -Provide jobs
- -Reduce flooding
- -Allow farming on lands that would otherwise be too dry
Define Seedig Clouds & Desalination:
- Seeding Clouds: Condensation nuclei & Silver Iodide
- Desalination: Removing salt from ocean water or brackish water to get fresh water.
What is water pollution?
•Physical, biological, or chemical change in water quality that adversely affects living organisms or makes water unsuitable for desired uses
Define Point Source & Nonpoint Source:
- Point Source- discharge pollution from specific locations
- -Factories, power plants, drain pipes
- Nonpoint Source- scattered or diffuse, having no specific location of discharge
- -Agricultural fields, feedlots, golf courses, residential construction sites
Define Atmospheric Depositon:
-contaminants carried by air currents and precipitated into watersheds or directly onto surface waters as rain, snow or dry particles
Define Coliform bacteria:
-intestinal bacteria; used to detect water contamination by animal wastes
Define Biochemical Oxygen Demand:
- •- amount of dissolved oxygen
- consumed by aquatic microorganisms. Used
- as a test for organic waste contamination from sewage, paper pulp and food
Define Oligotrophic, Eutrophic & Eutrophication
- •Oligotrophic - clear water and low biological
- •Eutrophic -rich in organisms and organic
- -Eutrophication -
- process of increasing nutrient levels and biological productivity
- •A renewable resource that develops
- gradually through the weathering of rocks and the accumulation of organic
Name the Soil Layers:
- O Horizon (Organic Layer): decomposed organisms
- A Horizon (Surface soil)
- E Horizon (washed out)B Horizon (Subsoil)C Horizon: Weathered rock fragments with little organic materials.
- Parent Material: the mineral material on which the soil is built, can be bedrock
Lack of nitrogen, potassium, and phosphorus often limits plant growth.
Define Biological Pests & Pesticides:
- Pests – organisms such as insects or
- fungi that compete with humans to consume agricultural crops.
- •Pesticides are chemicals that kill biological
- produced pesticides are the most common method of controlling pests in modern
- agricultural production.
Define sheet erosion:
- Soil erosion due to lack of vegetation in farming areas (after crops are harvested,
- the land is not vegetated).
Define Rill erosion & Stream Bank Erosion:
- -Rill erosion small rivulets of running water gather together and cut small channels
- -Stream bank Erosion washing away of soil from banks of streams and rivers
Define Contour plowing, Strip farming & Terracing:
Contour Plowing- plowing across slope to slow flow of water
Strip Farming - planting different crops in alternating strips along land contours
Terracing- shaping land to create level shelves of earth to hold water and soil
Define Minimum Till, Conservation Till & No-Till:
–less frequent plowing and cultivating
- Conservation-Till-uses a disc called a coulter to open a furrow just wide enough for seed
-drilling holes in ground for seed through mulch and ground cover
What is the Clean Water Act?
- (1972) established a National Pollution Discharge System which requires a permit for
- any entity dumping wastes in surface waters and requires disclosure of what is
- being dumped.
-Improvement in water quality, mostly due to sewage treatment
-But goals have not been fully met; 21,000 water bodies do not meet designated uses