Unit 9 Water Pollution
indicator species
Species that serve as early warnings that a community or an ecosystem is being damaged by disease-causing pathogens.
acid deposition
Sulfur oxides and nitrogen oxides, emitted by burning fossil fuels, enter the atmosphere-where they combine with oxygen and water to form sulfuric acid and nitric acid-and return to Earth's surface. -CAUSE WAS BY THE TALL SMOKESTACKS OF THE INDUSTRIAL PLANTS THAT WERE BURNING COAL AND RELEASING SULFUR DIOXIDE AND NITROGEN DIOXIDE -water bodies' pH was below 5 which can be lethal to many aquatic organisms.
b
Tests on water can be used to indicate the likelihood of human wastewater contamination by testing for indicator species such as a. Cryptosporidium b. fecal coliform bacteria c. Vibrio Cholerae bacteria d. Influenza e. Salmonella Typhi bacteria
d
The BOD measurement of a liter of healthy water was found to be 20 mg. The BOD measurement of a liter of more polluted water was 120 mg. Which of the following statements is correct? a. the healthy water produced 6 times as much oxygen as the polluted water. b. the polluted water produced 6 times as much oxygen as the healthy water. c. the healthy water consumed 6 times as much oxygen as the polluted water. d. the polluted water consumed 6 times as much oxygen as the healthy water. e. None of these answers are correct.
e
The BOD test is designed to directly measure a. how much light can pass to the bottom of the stream b. the amounts of nitrites in the water c. how rapidly the water is moving d. the amounts of coliform bacteria e. the rate at which oxygen is being consumed by microorganisms
d
The Clean Water Act I. Protects surface waters II. Protects groundwater III. Protects the diversity of aquatic species a. I only b. II only c. I and II only d. I and III only e. I, II, and III
oil tankers
oil and other petroleum products can also enter the oceans as spills from _______ ex: Exxon Valdez
nitrogen; phosphorus
What are the two elements that are part of decomposition and most important for limiting the abundance of producers?
Sediment
What has the highest pollutant by volume? This is caused when erosion from poor land management, fires, and construction carries soil into waterways
a
What health threat is commonly found in the water of older homes due to old plumbing systems? a. lead b. sulfates c. mercury d. arsenic e. phosphates
b
What is the first step of treating wastewater at a municipal sewage treatment plant? a. Use of bacteria to break down organic matter b. Solid waste material settles out c. Disinfection using chlorine or ozone d. Water is removed from sludge e. Water undergoes aeration to reduce offensive odors
E coli
What is the most common species of fecal coliform? -live naturally in humans and are not harmful -strains that can be deadly to very YOUNG and old or someone that possesses a weak immune system. -detecting e coli in a body of water indicates that human waste has entered the water
d
A heavy metal associated with the burning of coal is a. Lead b. Uranium c. Sulfur d. Mercury e. Carbon
dead zones
A large region of water that has very low oxygen concentrations, and therefore can't support aquatic life. ex: Mississippi River
b
A man-made pond constructed to hold animal waste is called a a. septic tank b. manure lagoon c. feed lot d. leach field e. sewage treatment plant
perchlorates
-harmful chemicals that contaminate the soil through rocket fuel (military rockets) -can leach from contaminated soil into the groundwater where they rest for many years. -human exposure to this can comes primarily from the consumption of contaminated food and water. It can effect the thyroid gland and reduce the production of hormones necessary fro proper functioning of the human body
d
A "green" wastewater treatment process includes all of the following EXCEPT a. the use of holding tanks b. an on-property wetland c. the use of microbes and algae d. the use of chemicals to remove harmful bacteria e. the use of pipes to move water
Sewage Treatment Plants
A facility that cleans the waste materials found in water that comes from sewers or drains from thousands of households PRIMARY TREATMENT & SECONDARY TREATMENT is used. -used in urban areas -needed for high population density and little open land.
a
A group of students did a bilogical oxygen demand study along a 30-mile section of a stream. The data they obtained is given in the graph above. Which of the following best describes the type of pollution at mile 0? a. Point source b. Thermal inversion c. Acid deposition d. Secondary pollutant e. Deep well
eutrophication
A process by which nutrients, particularly phosphorus and nitrogen, become highly concentrated in a body of water, leading to increased growth of organisms such as algae or cyanobacteria. ex: Chesapeake Bay
b
An abundance of which of the following creatures (and a lack of other creatures) would indicate that water is polluted? a. Trout and other game fish b. Sludge worms, anaerobic bacteria, and fungi c. Mayfly larva, stonefly larva, and damselfly nymphs d. Salamanders and turtles e. Dobsonfly larva, caddisfly larva, and grass shrimp
b
An important environmental safety feature of manure lagoons is a. a ledge for the cattle to walk on b. a liner to prevent leakage into groundwater c. the use of disinfectants to treat manure d. a secondary treatment to remove antibiotics e. an adequate water supply
a
Anaerobic bacteria, sludge worms, and fungi are most likely to be found in which part of this stream? a. 0 to 5 miles b. 10 to 15 miles c. 25 to 30 miles d. 10 to 20 miles e. 15 to 20 miles
b
Bacteria are beneficial to wastewater treatment because a. they help solid material to settle out of the wastewater b. they naturally break down organic matter c. the nutrients produced are beneficial to the treated water d. a and b are true e. all of the above are beneficial aspects
e
Concerns over the wide use of synthetic pesticides include all of the following unintended effects EXCEPT a. the pesticide may be lethal to nontarget species as well as target species b. pesticide use leads to an altered species composition of the community c. the chemistry of the inert ingredients d. physiological side effects on pest and nonpest species e. acidification of nearby streams
d
Dead zones, such as the one in the Gulf of Mexico that exists off the coast of Louisiana, are characterized by all of the following EXCEPT a. a reduced number of shellfish b. fish die-off events c. low oxygen concentrations in the water d. low nitrogen concentrations e. a reduced number of marine plant species
3
Once the septic tank begins operating how many layers develop int the septic tank. -anything that rises to the top = scum layer -middle = clean water layer= septage -the bottom, heavier than water = sludge
d
Environmental advantages of septic tanks include all of the following EXCEPT a. gravity is used to move the water b. water is returned to the local environment c. sewage is broken down by natural means d. no byproducts of water treatment remain e. harmful pathogens can be degraded by soil microorganisms
rapid growth
Eutrophication causes __________ __________ of algae, known as an algal bloom. The algae eventually dies and microbes rapidly begin digesting the dead algae and consumes oxygen.
a
For which substances does the EPA allow a MCL (maximum contaminant level) of 0 in drinking water? a. Giardia and Fecal coliform b. Giardia and Arsenic c. Mercury and Atrazine d. Mercury and Fecal coliform e. Benzene and Mercury
b
Genetically engineered bacteria are useful in the remediation of a. synthetic organic compounds b. oil spills c. nitrates and phosphates d. heavy metals e. sedimentation
d
Human wastewater entering into bodies of water can be dangerous because I. It causes a drop in the biological oxygen demand II. It can lead to cultural eutrophication III. The wastewater can carry pathogens a. I only b. II only c. III only d. II and III only e. I, II, and III
more
If you have higher BOD values this indicates your water is _____ polluted by wastewater
less
If you have lower BOD values this indicates your water is ____ polluted by wastewater
platforms
One source of oil in the water comes from drilling for undersea oil using offshore _______ -these _________ experience leaks and can cause a pipe explosion
a
Mercury is especially dangerous to the general public due to a. its accumulation as it moves up the aquatic food chain b. the incineration of household waste c. the lack of regulation against emissions in the United States d. its effect on the respiratory system of infants e. it occurring naturally in bedrock
c
Methods used to remove spilled oil from the surface of the ocean include I. containment booms and oil vacuums II. chemical dispersants III. large screens a. I only b. II only c. I and II only d. I and III only e. I, II, and III
d
Negative environmental effects of using high-pressure water hoses on rocky coastlines contaminated with spilled oil include all of the following EXCEPT a. removal of fine-grained sediment b. displacement of native plant life c. washing away of microorganisms d. cost of energy to heat water to make steam e. many organisms were unable to recolonize the coastline
c
Noise pollution in water is a significant problem for a. jellyfish b. sea turtles c. whales d. marine birds e. phytoplankton
N and P
Nutrients ______ and _____ stimulate plant growth. As algae grow in excess, they die and the decomposition of their bodies leads to oxygen depletion or hypoxia that cay cause fish kills
cultural eutrophication
Overnourishment of aquatic ecosystems with plant nutrients (mostly nitrates and phosphates) because of human activities such as agriculture, urbanization, and discharges from industrial plants and sewage treatment plants.
a
Possible sources of petroleum in the ocean waters include all of the following EXCEPT a. naturally occurring plumes from oceanic trenches b. natural seeps from the ocean floor c. oil tanker transportation d. oil platform leaks e. tanker or platform accidents
a
Primary treatment in a sewage treatment plant is designed to a. remove pathogens from wastewater b. remove solids from wastewater c. create sludge for use as fertilizer d. move water from municipalities to the plant e. recycle water
b
Put the events leading to cultural eutrophication in the correct order. W - leaching of nutrients from fertilized agricultural lands X - fish die-off Y - algal bloom a. W->X->Y b. W->Y->X c. X->Y->W d. X->W->Y e. Y->X->W
e
The United States legislation that empowers the EPA to establish maximum contaminant levels in drinking water is a. The Clean Water Act b. The Superfund Act c. The Clean Air Act d. The MCL Act e. The Safe Drinking Water Act
c
The WHO estimates that approximately 1.1 billion people worldwide do not have access to sufficient safe-water supplies. This number represents about ____ of the world population. a. 1/20 b. 1/10 c. 1/6 d. 1/4 e. 1/3
b
The difference between a point source and a nonpoint source of water pollution is a. a nonpoint source is easily identifiable b. point sources can be targeted for reduction c. nonpoint sources tend to be factory outputs d. point sources tend to be agricultural in nature e. nonpoint sources are less harmful to the environment
c
The environmental costs of moving contaminating industries from developed countries to developing countries include I. less restrictive environmental laws II. increased pollution due to less dense human population III. additional pollution in the developing country a. I only b. II only c. I and III only d. II and III only e. I, II, and III
Primary Treatment
The goal of __________ _________ in a sewage treatment plant is to get the SOLID WASTE MATERIAL to settle out of the wastewater. (GET SLUDGE OUT) -this solid material is then dried and classified as SLUDGE. -bacteria start to eat the sludge to remove as much of the bacteria and pathogens present in the water. -most of the water is removed for transportation and the sludge is taken to a landfill to be burned or converted into fertilizer pellets.
Secondary Treatment
The goal of __________ ___________ in a sewage treatment plant is to use BACTERIA to BREAK DOWN 85 to 90% of the organic matter and convert it to CO2 & inorganic nutrients such as nitrogen and phosphorous. -aeration of the water to promote the growth of aerobic bacteria, which emit less offensive odors. -This treated waters sits for a couple days and allows the particles to settle out. -The particles are then added to the sludge from the primary treatment. -THE REMAINING WATER IS DISINFECTED, USING CHLORINE OZONE. OR ULTRAVIOLET LIGHT TO KILL ANY REMAINING PATHOGENS -CLEAN WATER IS THEN RELEASED IN NEARBY LAKES AND RIVERS
e
The highest priority of the Clean Water Act is to provide a. funds to increase recycling participation b. guidance about toxic chemical disposal c. funds to reclaim old strip mines d. policies to lessen the amount of oil spills in the ocean e. policies to attain fishable and swimmable waters in the United States
a
The most prevalent way to treat human waste in rural areas where a large amount of land is available is a. septic systems b. sewage treatment plants c. manure lagoons d. stormwater drainage systems e. collective ponds
a
The pollution of waterways creating conditions in which productivity is decreased and gills of bottom dwelling organisms are clogged is due to a. erosion and sedimentation b. noise pollution c. urbanization d. mining dams e. thermal pollution
e
The resulting acid deposition from SO2 emissions can occur as a. acidic rain b. acidic snow c. dry-acid deposition d. a and b only e. all of the above are forms of acid deposition
GEB (Genetically Engineered Bacteria)
What is the third approach to clean up oil uses by natural occurring bacterium that obtain energy by eating oil from natural seeps.
Cuyahoga
What river in Ohio suffered consequences from the disposal of industrial compounds? -river caught on fire and burned
d
To decrease the likelihood of cultural eutrophication from the effluent released from a water treatment facility, sewage plants may include a a. secondary treatment of using bacteria to breakdown algae b. secondary treatment of using ozone for disinfection c. secondary treatment of removing nitrogen and phosphorous d. tertiary treatment of removing nitrogen and phosphorous e. tertiary treatment of using bacteria to breakdown algae
true
True or False: It is more difficult to control a nonpoint source than a point source.
True
True or False: Leachate, Leaking Underground Storage Tanks, and saltwater instruction are common sources of groundwater pollution
true
True or False: These are a broad range of pollutants that can be found in water included human and animal waste -inorganic substances -inorganic compounds -synthetic organic compounds -nonchemical pollutants
True
True or False: Wastewater can carry a variety of illness-causing viruses, bacteria, and parasites that we call pathogens
fecal coliform
Type of bacteria that are harmless microorganisms that live in the intestines of human beings and other animals.
a
Using water for industrial processes within a closed system, where the hot water is cooled in a tower and then recycled for heating again, reduces a. thermal pollution by not releasing heated water into nature b. the ambient temperature of the local area c. the need for cogeneration d. the effects of sedimentation e. noise pollution by containing the movement of the water
c
Waste from which of the following is an example of a nonpoint source of water pollution? a. waste overflow from a water treatment plant due to excessive rains b. mercury emissions from coal burning power plants c. runoff from sprayed agricultural fields d. dumping at a abandoned landfill e. acid drainage from an empty mine
d
What substance is believed to be responsible for the development of eggs in the testes of some male fish? a. DDT b. PBDEs c. Perchlorates d. Reproductive hormones e. PCBs
thermal shock
When a source of thermal pollution first starts of stops, fish and other organisms adapted to particular temperature range can be killed by the abrupt change in water temperature. Also increase their respiration rate
b
Which Standard is this?? identify appropriate uses for the state's surface waters, including aquatic life, recreation, and sources of public water supply (or drinking water). The criteria for evaluating support of those uses include dissolved oxygen, temperature, pH, dissolved minerals, toxic substances, and bacteria. Statewide standards may be revised on a site-specific basis when sufficient information is available. a) The Texas Surface Water Quality Standards b) Water quality standards c) Drinking water standards
c
Which Standard is this?? based on Maximum Contaminant Levels (MCLs) established for a variety of contaminants including microorganisms, inorganic and organic chemicals. These levels consider both the harmful effect of the contaminant and the feasibility and cost of reducing the substance to a level. a) The Texas Surface Water Quality Standards b) Water quality standards c) Drinking water standards
e
Which of the following are related to overflows of sewage in the United States? a. Human illness due to the eating of contaminated shellfish b. Human illness due to swimming in contaminated waters c. Human illness due to drinking of contaminated waters d. The pumping of untreated water from plants due to heavy rain events. e. All of the above are related to overflows of sewage in the United States
e
Which of the following are types of wastewater? I. Sewage water from toilets II. Water from showering and bathing III. Water from washing clothes a. I only b. II only c. III only d. I and II only e. I, II, and III
e
Which of the following correctly explains what happens to the level of dissolved oxygen in water when organic waste is put in the water? a. The levels would remain the same after the waste was added. b. The levels would increase because of the availability of nutrients to animals that live in the water. c. The levels would increase because of the higher temperatures of the water. d. The levels would decrease because of the waste absorbing the oxygen. e. The levels would decrease because of the bacteria feeding off the waste and using the oxygen to live.
e
Which of the following diseases is NOT caused by wastewater exposure? a. Cryptosporidium b. Cholera c. Typhoid fever d. Stomach flu e. Malaria
b
Which of the following gives the correct order of processing sanitary waste in a sewage treatment plant? a. Disinfection--Breakdown of organics by bacteria--Solid Separation b. Solid Separation--Breakdown of organics by bacteria--Disinfection c. Solid Separation--Disinfection--Breakdown of organics by bacteria d. Breakdown of organics by bacteria--Solid Separation--Disinfection e. Breakdown of organics by bacteria--Disinfection--Solid Separation
e
Which of the following is a possible end result for sludge from a sewage treatment plant? I. Deposited in a landfill II. Incinerated III. Used as a fertilizer a. I only b. II only c. III only d. I and II only e. I, II, and III
organic substances
Which one is not an example of water pollutants? -human & animal waste -inorganic substances -organic compounds -synthetic chemicals -organic substances -pathogens -nonchemical pollutants such as solid, waste, heat, noise and light
c
Which pollutant is most likely to be naturally released into groundwater supplies, without human intervention? a. phosphates b. lead c. arsenic d. mercury e. sulfates
a
Which pollutant or pollutants are most likely to create eutrophic areas? a. nitrates and phosphates b. synthetic organic compounds c. heavy metals d. solid waste e. pharmaceuticals
a
Which standard is this? establish explicit goals for the quality of streams, rivers, lakes, and bays throughout the state. The Standards are developed to maintain the quality of surface waters in Texas so that it supports public health and enjoyment and protects aquatic life, consistent with the sustainable economic development of the state. a) The Texas Surface Water Quality Standards b) Water quality standards c) Drinking water standards
42
Who much percent of the world's population lacks access to proper sanitation? (Half of the people live in China and India.)
1/6
______ of the world's population do not have access to sufficient supplies of safe drinking water.
inert Pesticides
_________ serve as an important role in helping to control pest organisms that pose a threat to crop proaction and human health. But they have huge drawbacks 1) most pesticides do not target particular species of organism, but generally kill a large variety of related organism 2) they can alter physiological function and have major side effects.ex: DDT to target a nerve system 3) the role of inert ingredients - they are additives that make a pesticide more effective, allowing it to dissolve in water for spraying or to penetrate inside a pest specie.
septic tank
a large container that receives wastewater from the house. Having a capacity of 1,900 to 4,700 liters. Part of the septic system. -buried underground adjacent to the house. -wastewater forms from the house and flows into the tank at one need and leaves the tank at another. Once the tank has been operating for some time it will have 3 layers -NO ELECTRICITY NEEDED DUE TO THE ADVANTAGE OF GRAVITY
thermal pollution
a type of non chemical water pollution that occurs when human activities cause a substantial change in the temperature of water, -Harm to lakes and rivers resulting from the release of excessive waste heat into them
pyrite
a type of rock formed from the combo of water and air which produce iron and hydrogen ions. This chemical reactions produces acidic water with a low pH. These can rise up to the surface and allows it to feed into the stream.
Noise Pollution
any unwanted, disturbing, or harmful sound that impairs or interferes with hearing, causes stress, hampers concentration and work efficiency, or causes accidents ex: whales and sonar
water pollution
contamination of streams, rivers, lakes, oceans, or groundwater with substances produced through human activities and that negatively affect organism.
point source
distinct locations such as a particular factory that pumps its waste into a nearby stream or a sewage treatment plant that discharges its wastewater DIRECTLY from a pipe into the ocean.
gasses; particles
dry acid deposition occurs as _____ and _____ that attach to the surface of plants, soil, and water.
Safe Drinking Water Act
enacted in 1974 and revised significantly in 1986 and 1996, it set the standards for safe drinking water; establishes MCLs for a number of different elements or substances in both surface and groundwater.
Clean Water Act
expansion of the 1948 Federal Water Pollution Control Act in 1972 to support the protection and propagation of fish, shellfish, and wildlife and recreation in an on the water by maintaining, and when necessary, restoring the chemical, physical, and biological propoerties of natural waters; established standards and authorized a permitting system (NPDES) to control how much pollution could be discharged into a stream segment.
decomposition
first, when wastewater is dumped into bodies of water, the water naturally undergoes ________ by bacteria.-----> create a large demand for oxygen
pathogens
harmful virus that is responsible for a number of diseases that can be contracted by humans or other organisms that come in contact with or ingest the water. Cause: cholera, typhoid fever, stomach flu, and diarrhea
Synthetic Organic Compounds
human made compounds that enter the water supply either from a industrial point source or a non point source. -They include pesticides, pharmaceuticals, and industrial cleaners -toxic and can cause genetic defects and interfere with sexual development and growth
manure lagoons
human-made ponds lined with rubber built to handle large quantities of manure produced by livestock DISADVANTAGES: -possibility of leaking in liner and underlying water to be contaminated by seeping water -overflow adjacent water body -application of manure as fertilizer can create runoff that goes to nearby ponds.
septage
layer in the septic tank in the middle (clean) -this water moves out of the septic tank by gravity into several underground pipes laid out across a lawn below the surface (leach field)
scum
layer in the septic tank where it rises (dirty)
sludge
layer in the septic tank where it sinks (dirty)
soluble
low pH water an also cause many other harmful metal ions to become ______. These include Zinc, copper, aluminum, and manganese.
BOD
measure of the demand that is present for the available DO. In natural waters there is a level of BOD that is normal. When oxygen demanding wastes are discharged to a waterway, bacterial
nonpoint sources
more diffused areas such as an entire farming region, a suburban community with many lawns and septic systems, or storm runoff from parking lots
bogs
naturally Acidic waters is what?
septic systems
small, simple system with two components: septic tank and a leach field -used in rural areas of low population -houses often carry their own sewage treatment called this
sulfuric; nitrogen
tall smokestacks that were real sing and burning _________ and ________dioxide have caused acidic deposition both land and water
BOD (biochemical oxygen demand)
the amount of oxygen a quantity of water uses over a period of time at a specific temperature. -Measures the oxygen-demanding waste
Dissolved Oxygen
the amount of oxygen dissolved in water, expressed as mg/l. It is essential to aquatic animal respiration and water that is saturated will support the most diverse aquatic community.
leach field
the combination of pipes and lawn below the surface where the septage enters where it FILTERS THROUGH.
manure lagoon
the most prevalent system to treat waste from large livestock is?
fertile
the nutrients that are released from the wastewater make the water more ________ and cause a wide variety of disease-causing organisms
eutrophication
the process of adding nutrients to an aquatic system -caused by natural runoff or when human actions create inputs
chemicals
the second way treating floating oil is to apply _______ to break up the oil before it hits shoreline.
oil containment booms
these are booms that consists of plastic barriers coating on the surface of the water and extending down into the water to suck up as much oil as possible.
PBDE
these are industrial compounds that are most known as flame retardants added to a wide variety of items including construction materials, furniture, electrical components, and clothing -exposure of this can lead to brain damage in children
Pathogenic microbes
these cause a serious problem in polluted water. They include bacteria that cuase typhoid fever, cholera, entertitus and bacterial dysentery, viruses that cause infectious hepatitis (Type B), parasitic protozoa that cause ameobic dysentery, giardiasis and cryptosporidium, and parasitic worms that cause schistosomiasis.
PCB
these industrial compounds were used in manufacturing plastics and insulting electrical transformers until 1979. -Because of their long persistence, PCBs are still present in the environment -ingested PCBsare lethal and carcinogenic.
lead
this heavy mateo poses a serious health threat -it is rarely found in natural sources of drinking water, but instead contaminates water when the water passes through the pipes of older homes and contains lined lead and various metals. -fetuses and infants are most sensitive to this and exposure can cause damage to the brain, nervous system, and kidneys.
arsenic
this heavy metal occurs NATURALLY in the Earth's crust and can dissolve into the groundwater -human activity also contributes to higher ______ concentrations in groundwater 2. ex: mining -this metal is mostly found in the midwest and west -it can cause cancer of the skin, lungs, kidneys, and bladder. These illnesses can take 10 years or more after exposure to develop
coliform bacteria
this is an indication that water is polluted by the waste of humans or animals
Pollution tolerance
this is an indicator that organisms have been exposed to pollution and survived or even thrived
DDT
this is an insecticide designed to target nerve transmissions in insects, the chemical can MOVE UP AQUATIC FOOD CHAIN all the way to eagles that consume fish.
oxygen-demanding waste
this is organic matter that enters a body of water and feeds the growth of microbes that are decomposers. The more waste, the more microbes grow and the more oxygen they demand
mercury
this naturally occurring heavy metal is found in water due to human activities ex: burning fossil fuels, coal, incineration of garbage hazardous waste, medical supplies, raw materials that go into the manufacturing of cement for construction and dental supplies -mercury emitted by these actives is called Inorganic Mercury (Hg) This mercury then turns into Methlymercury that can run into nearby waterways or infiltrate the soil. Harmful to infants and fetuses
true
true or false: low pH in water bodies also occurs when very acidic water comes from below ground - due to the problem of underground mines that, once abandoned, flood with groundwater.
coal scrubbers
used to combat acid desposition by passing hot gases through limestone mixtures
screening, settling, and skimming
wat are the three S's for the technique of primary treatment?
wastewater
water produced by human activities including human sewage from toilets and gray water from bathing and washing clothes and dishes
rain; snow
wet acid deposition occurs in the form of what and what??
cholera; hepatitis
what are the two major water borne disease?
septic systems; sewage treatment plants
what are the two widespread systems for treating human sewage??
pharmaceutical
what drugs mimic estrogen that are connected to male fish growing female eggs in the wildlife?
Methlymercury
when inorganic mercury converts into ____________ in wetlands and lakes. -damage the central nervous system in young children and embryos = impairment of coordination and sense of touch, taste, and sight -OCCURS MOSTLY THROUGH EATING FISH