Unit 8

Question 1

Coral bleaching

Answer 1

high water temperatures cause the algae part of coral to be expelled, and if there is no algae there is no coral. Coral turns snow white and die. Mass bleaching is becoming more common and more intense

Question 2

Impacts of oil spills

Answer 2

Poisoning: is toxic, so organisms die from acute or chronic exposure to it, usually from ingestion or absorption through tissues
Hypothermia/drowning: oil interferes with natural oils that keep water bird feathers waterproof. If water gets to the skin, the bird loses buoyancy and insulation. Marine animals have similar issues
Loss of productivity: in high densities, oil floating on the surface can block sunlight from producers, limiting photosynthesis and productivity
Economic impacts: no one wants to fish in an oil spill, or visit oil covered beaches. Coastal economies and industries suffer major impacts

Question 3

DO

Answer 3

DO = dissolved oxygen
Higher DO levels = more biodiversity (usually) because there is more oxygen to breath

Question 4

BOD

Answer 4

BOD = Biochemical Oxygen Demand - A measurement used to determine how much oxygen is used by a volume of water over time to support the life there
The more living things in a volume of water, the higher the BOD, and thus the lower DO

Question 5

oxygen sag curve

Answer 5

Represent the DO levels in a body of water based on the distance from a pollution source

Question 6

Oceanic dead zones

Answer 6

Occurs near river mouths, especially from rivers passing through agricultural regions because runoff from farms adds nitrates, phosphates, and other nutrients to the water. Once the river empties in the ocean, algae begins to bloom and increases microorganism numbers, which increases the BOD and decreases the DO level to an extreme, which can create areas with no living things whatsoever

Question 7

heavy metals in water: mercury

Answer 7

highly toxic in large quantities, but usually only in small amounts naturally. Industrial activity, especially burning fossil fuels, release more mercury into the environment
When released into aquatic environments, bacteria convert it to methylmercury which is even worse,

Question 8

heavy metals in water: lead

Answer 8

Most common exposure comes from contaminated pipes or contaminated runoff into water supply, since there is very little naturally
Impacts most felt by children as it stunts brain growth

Question 9

heavy metals in water: arsenic

Answer 9

Is naturally occurring but can also be brought to the surface by mining, which can then infiltrate groundwater. Is pretty easy to remove by filtration but linked with many kinds of cancer

Question 10

acute vs chronic diseases

Answer 10

Acute: Rapidly impairs the functioning of a person’s body
Chronic: Slowly impairs the functioning of a person’s body

Question 11

infectious diseases

Answer 11

Caused by pathogens and must be transferred by something
Ex. viruses, bacteria, fungi, parasites, etc

Question 12

epidemic vs pandemic

Answer 12

Epidemic: when a pathogen causes a rapid increase in disease in one area
Pandemic: when an epidemic occurs over a large geographic region

Question 13

dose response curve

Answer 13

will tell a doctor how much of a substance is required to get a specific effect

Question 14

plague

Answer 14

An infectious disease caused by bacteria on fleas, carried by mice and rates( examples are the bubonic plague or black death)
Symptoms: swollen glands, black spots on skin, and pain
Although very small outbreaks still sometimes occur, modern medicine is very good at preventing further infections

Question 15

malaria

Answer 15

Caused by a few species of protists- the parasite spends part of its life in a mosquito, and the other part in a human
flu-like symptoms
While malaria has been eliminated from the US for 50 years, it is still a major problem in other locations, especially African countries

Question 16

tuberculosis

Answer 16

A very contagious disease caused by bacteria that infects the lung
Transfers from person to person like covid
Symptoms: feeling weak, sweating, and coughing up blood
Now, antibiotics can help, but once again, this is still not readily available in developing countries. It is the leading cause of death in the developing world

Question 17

HIV/AIDS

Answer 17

Acquired Immune Deficiency Syndrome (AIDS) and Human Immunodeficiency Virus (HIV).
Spread through sexual contact and blood transfusions, and could be generational as well.
Weakens immune systems; super high mortality rate
New antiviral drugs are able to contain virus populations within a human body and extend lifespans, but it is very expensive

Question 18

Ebla Hemorrhagic Diseases

Answer 18

Infections virus with high death rates
Symptoms: fever, vomiting, internal and external bleeding, and death can occur within 2 weeks
Only drugs are experimental

Question 19

Mad Cow Disease

Answer 19

A neurological disease where prions mutate into deadly pathogens (good proteins become evil proteins) that slowly damage a cow’s nervous system and kinda go mad
Still mostly for cows, but technically can be transferred to people and becomes Creutzfeldt-Jakob disease
The nice thing is that transmission requires an uninfected organism to eat another infected organism, which is fine for cows in a field but not people eating the meat of those cows

Question 20

Swine / Bird flu

Answer 20

both jumped from their respective animals to people through a virus. Because it’s rare for people we have fewer defenses against it, makes it more harmful
There are now vaccines which help, but thousands have died in pandemics (Spanish flu). sometimes governments just kill all the birds to get rid of it

Question 21

SARS and MERS

Answer 21

Severe acute respiratory syndrome (SARS) is caused by another type of virus called the coronavirus
that’s all I got

Question 22

West Nile Virus

Answer 22

Live in birds and transmitted between the two by mosquitoes- spread to humans through mosquitoes as well
Causes inflammation of the brain leading to illness and death
Pretty rare though right now

Question 23

Lyme Disease

Answer 23

Caused by bacteria that are transmitted by ticks by them feeding on blood
Most infections are in the northeast, and often a telltale sign is a red bullseye at the site of the attachment
Most infections are cured by antibiotics, but effects can persist for years afterwards for some

Question 24

Zika Virus Disease

Answer 24

Caused by a pathogen, transferred by mosquito bites or sexual contact
Makes babies be born with small heads and damaged brains
For the originally affected (adults), there’s usually only a few days or weeks of rashes and fevers, but then it subsides. The real danger is with babies
Sadly, there are currently no known treatments

Question 25

human health in developing and developed countries

Answer 25

Many developing or low income countries have a much harder time preventing and combating disease (less nutrition, expensive drugs, etc.}
In developed countries, problems like lack of movement cause new problems

Question 26

pathogen resistance to antibiotics

Answer 26

Particularly important when people start a drug but don’t finish with it, so the strain inside them becomes resistant to the drug they’ve been taking (like a vaccine but for the virus itself)
New strains are even more dangerous and harder to get rid of

Question 27

Military compounds

Answer 27

Sometimes contaminate the soil in regions of the world where military rockets are manufactured, tested, or dismantled. Easily leach from contaminated soil into the ground, where they stay for years
Can effect thyroid gland and reduce the production of hormones necessary for proper functioning of the human body
Example: perchlorates (used in rocket fuels and harmful)

Question 28

industrial compounds

Answer 28

Polychlorinated biphenyls (PCBs) = A group of industrial compounds used to manufacture plastics and insulate electrical transformers, and responsible for many environmental problems. Ingested PCBs are lethal and carcinogen, or cancer-causing.
Have since been banned, but still exist in the environment

Question 29

Neurotoxins

Answer 29

Disrupts the nervous system of an organism (as well as the brain and immune system sometimes
Examples: Lead (from paint and gas), mercury (from burning coal, fish consumption), many insecticides

Question 30

Carcinogens

Answer 30

Causes cell damage and lead to uncontrolled growth of these cells either by interfering with the normal metabolic processes of the cell or by damaging the genetic material of the cell
Examples:
Asbestos (from building materials), Radon (from soil and water), Vinyl Chloride (from industry and water in said pipes) all cause lung cancer
Arsenic (from mining and groundwater) causes cancer, and PCBs (industry) causes cancer, liver damage and impaired learning
Mutagens: a type of carcinogen that causes damage to the genetic material of a cell.

Question 31

Teratogens

Answer 31

a chemical that interferes with the normal development of embryos or fetuses (ex. alcohol)

Question 32

Allergens

Answer 32

a chemical that causes allergic reactions (immune system said nuh uh) ex. peanuts, milk, drugs like penicillin

Question 33

Endocrine disruptors

Answer 33

a chemical that interferes with the normal functioning of hormones in an animal’s body. extra hormones in wastewater can mess with the hormones of those who interact
Atrazine, DDT, and phthalates are all examples that cause feminization of males

Question 34

Persistent Organic Pollutants (POPs)

Answer 34

Persistent Organic Pollutants, which requires them to:
Remain intact for a very long time (years)
Becomes widely distributed in the environment from natural processes
Accumulate in living organisms (bioaccumulate and magnify)
Be toxic
examples include the dirty dozen!!

Question 35

LD-50 vs ED-50

Answer 35

LD- 50: the lethal dose of a chemical that kills 50 percent of the individuals in a dose-response study
ED-50: the effective dose of a chemical that causes 50 percent of the individuals in a dose-response study to display a harmful, but nonlethal, effect.

Question 36

NOELs

Answer 36

No-observed effect level (NOEL): the highest concentration of a chemical that causes no lethal of sublethal effects

Question 37

sublethal effect

Answer 37

Sublethal effect: the effect of an environmental hazard that is not lethal, but which may impair an organism’s behavior, physiology, or reproduction.

Question 38

indicator species

Answer 38

Indicator species: a species that indicates whether or not pathogens that are disease causing are present

Question 39

septic systems

Answer 39

Septic tank: receives wastewater from the house and is buried underground next to the house (buried underground DOWN HILL from the house)
the wastewater forms layers - the top is anything that floats and is the scum layer. Things heavier than water, which includes many pathogens, go to the bottom to form a sludge layer. The middle is somewhat clean water called septage.
The septage moves outside through pipes under a lawn called the leach field. The water from the pipes seeps through and into the soil, and the harmful pathogens still inside are outcompeted by the other microorganisms in the soil or septic tanks.
the sludge must be pumped out periodically, but otherwise it is a great way to dispose of waste independently, especially in rural areas!

Question 40

sewage treatment plants

Question 41

risk equation but I don’t think we need it

Answer 41

risk = probability of being exposed to a hazard / probability of being harmed if exposed

Question 42

“innocent until proven guilty” vs “precautionary” principles in terms of risk

Answer 42

Innocent until guilty: Based on the belief that a potential hazard should not be considered dangerous until there is evidence that it actually causes harm. Causes less panic and stuff, but this means things can go unnoticed for decades and cause more harm
Precautionary: When a hazard is not certain but plausible, take action to reduce it’s potential damage. This makes it harder to introduce new chemicals that are beneficial, but prevents more harmful ones from ever getting out

Question 43

Stockholm convention

Answer 43

127 nations gathered to restrict the use of some chemicals globally
Produced a list of 12 chemicals to be phased out or reduced, and are known as the “dirty dozen” (which are all basically endocrine disruptors)

Question 44

problems with raw wastewater

Answer 44

• Release of nutrients (Similar to a CAFO, increases BOD)
• Disease causing pathogens released (often from human waste, includes typhoid fever, cholera, hepatitis, etc.)
  these problems are much more prominent in the developing world now rather than the developed

Question 45

primary treatment in sewage plants

Answer 45

Remove organic solids from the water, like a very large series of septic tanks
Non-organic or compostable solids are strained out before they reach the settling tank (bar screen)
Grid chamber and primary clarifier: sediments, inorganic and organic solids settle to the bottom where they can be pumped away. Also called sludge
The liquid waste (effluent) then moves on to secondary treatment

Question 46

secondary treatment in sewage plants

Answer 46

Uses bacteria to breakdown 85%-90% of the organic material remaining in the wastewater
In order to promote bacteria growth, these tanks are aerated and look like they are boiling
Organic waste is turned into CO2 and inorganic nutrients
Effluent is pumped to a secondary clarifier for final solid removal
Eventually, water is disinfected with chlorine, ozone and/or UV light

Question 47

tertiary treatment

Answer 47

optional, just gets rid of the extra inorganic compounds like nitrates or phosphates that would promote algae growth

Question 48

sanitary landfills

Answer 48

basically better landfills
Uses clay or plastic liner to prevent leachate from escaping
Leachate: liquid that contains elevated levels of pollutants as a result of having passed through municipal solid waste or contaminated soil
A leachate collection system: attached to a wastewater treatment facility, but is sometimes too toxic so is treated separately
Stormwater collection system: to prevent a cereal bowl
Cap: layers of dirt and plastic that seal the top of the pit
Methane capture system: controls the buildup of methane beneath the cap

Question 49

incineration of trash

Answer 49

Burns waste to rescue volume and mass
Most is converted to CO2 and water but can also produce energy@!

Question 50

open vs closed loops in recycling

Answer 50

Closed loop: no input of new materials - original material is transformed into that same material again
Open loop: One product is recycled into a new, different product