water pollution: affecting and improving water quality
TRANSCRIPT
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Water Pollution:
affecting and improving water quality
Types of Pollutants
Causes of Pollutants
Impact of Pollutants
Sources of Pollutants
Solutions to Water Pollution
Types of Water Pollutants
• Chemical pollution
Inorganic Nutrients (like nitrates and phosphates)
Dead Organic Matter (like feces)
Synthetic organic compounds (like pesticides, flame retardats, PCBs)
• Biological pollution
Disease-Causing organisms (like bacteria)
Invasive organisms (like zebra mussel)
• Physical pollution
Sediments (like soil particles)
Thermal Pollution (cold water or warm water)
Water Pollution: Change in the chemical, physical
and biological composition of water
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Biological Pollutants: Pathogens • Cause:
Animal waste from
sewage, feedlots runoff
and urban runoff
• Impact: Waterborne disease from viruses, bacteria, and others
contributes to 5 million deaths per year.
17% of otters dying from brain disease
Biological Pollutant: Introduced Species
Cause: ships, boats and even boots
Impact of Zebra Mussel:
Great Lakes industry and business lost $5 billion in 10 yr
In 2005,
Federal judge told the EPA to regulate ballast water from
ships that enter U.S
New Zealand Mudsnails in LA
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Physical pollution: Adding Sediment •Causes?
Erosion of soil from mining, deforestation, urban runoff, and farming
puts sediment into waterways
•Impact: can harm animals and plants of the ecosystem
Physical pollution: Removing Sediment
Impact: can harm the animals and plants of the ecosystem
4/8 fish native to the Grand Canyon
have already become extinct
Cause?
Dams
90% of the sediment builds up behind
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Physical Pollution: Temperature Cause?
Cold water is released below dams,
harming native fish downstream
Warm water from power plants
Kills billions of fish eggs, larva, etc
Warm water inhibits growth of kelp and
eelgrass
Impact:
Kills billions of fish eggs, larva, etc
Warm water inhibits growth of kelp and
eelgrass
Chemical Pollution: Inorganic Nutrients
• Impact: Eutrophication (ending with hypoxia)
Example: the hypoxic zone in the Gulf of Mexico
• Cause? phosphates or nitrates in
fertilizers, detergents, animal waste
from irrigation runoff, urban runoff, sewage
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Chemical Pollutant: dead organic material • Impact: Hypoxia
low level of dissolved oxygen in water due to
high levels of decomposition (biological oxygen demand BOD)
Fish and other organisms are not able to survive
• Cause?
Animal waste from
sewage, feedlots, urban runoff
Chemical Pollution: POP’S POP Global Historical Use/Source
aldrin and dieldrin Insecticides used on crops such as corn and cotton; also used for termite control.
chlordane Insecticide used on crops, including vegetables, small grains, potatoes,
sugarcane, sugar beets, fruits, nuts, citrus, and cotton. Used on home
lawn and garden pests. Also used extensively to control termites.
DDT Insecticide used on agricultural crops, primarily cotton, and insects that carry diseases such as
malaria and typhus.
endrin
Insecticide used on crops such as
cotton and grains; also used to control rodents.
mirex Insecticide used to combat fire ants, termites, and mealybugs.
Also used as a fire retardant in plastics, rubber, and electrical products.
heptachlor Insecticide used primarily against soil insects and termites. Also used against some crop pests and
to combat malaria.
hexachlorobenzene
Fungicide used for seed treatment.
Also an industrial chemical used to make fireworks, ammunition, synthetic rubber, and other
substances.
Also unintentionally produced during combustion and the manufacture of
certain chemicals.
Also an impurity in certain pesticides.
PCBs Used for a variety of industrial processes and purposes, including in electrical
transformers and capacitors, as heat exchange fluids, as paint additives, in
carbonless copy paper, and in plastics.
Also unintentionally produced during combustion.
toxaphene
Insecticide used to control pests on crops and livestock, and to kill unwanted fish in lakes.
dioxins and furans
Unintentionally produced during most forms of combustion, including burning of municipal and
medical wastes, backyard burning of trash, and industrial processes.
Also can be found as trace contaminants in certain herbicides, wood preservatives, and in PCB
mixtures.
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POPs: Why are they of concern?
1. Persist in the environment
Chemically, very stable,
DDT and PCBs banned in 70’s
but still present today
2. Capable of long-range transport
POPs: Why are they of concern? 3. Bioaccumulate in human and animal tissue: fat soluble
4. Biomagnify in food chains
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POPs: Why are they of concern?
5. Impact on health of humans and wildlife
Carcinogens: cause cancer
Teratogens: cause birth defects
Neurotoxins: damage nervous system
Endocrine disruptors: interfere with hormones
Endocrine disruptors are synthetic chemicals
that disrupt the endocrine system
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• The key concerns noted in the State of the Science of Endocrine Disrupting Chemicals – 2012
(http://www.who.int/ceh/publications/endocrine/en/index.html) are as follows:
• Human and wildlife health depends on the ability to reproduce and develop normally. This is not
possible without a healthy endocrine system.
• Three strands of evidence fuel concerns over endocrine disruptors:
– The high incidence and the increasing trends of many endocrine-related disorders in
humans;
– Observations of endocrine-related effects in wildlife populations;
– The identification of chemicals with endocrine disrupting properties linked to disease
outcomes in laboratory studies.
• Many endocrine-related diseases and disorders are on the rise.
– Large proportions (up to 40%) of young men in some countries have low semen quality,
which reduces their ability to father children.
– The incidence of genital malformations, such as non-descending testes (cryptorchidisms)
and penile malformations (hypospadias), in baby boys has increased over time or levelled off
at unfavourably high rates.
– The incidence of adverse pregnancy outcomes, such as preterm birth and low birth weight,
has increased in many countries.
– Neurobehavioural disorders associated with thyroid disruption affect a high proportion of
children in some countries and have increased over past decades.
– Global rates of endocrine-related cancers (breast, endometrial, ovarian, prostate, testicular
and thyroid) have been increasing over the past 40–50 years.
– There is a trend towards earlier onset of breast development in young girls in all countries
where this has been studied. This is a risk factor for breast cancer.
– The prevalence of obesity and type 2 diabetes has dramatically increased worldwide over the
last 40 years. WHO estimates that 1.5 billion adults worldwide are overweight or obese and
that the number with type 2 diabetes increased from 153 million to 347 million between 1980
and 2008.
POPs: How are we exposed to them?
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POPs: How are they tested Traditional toxicity tests:
-Test only one chemical - Dose-response curve
Concerns?
Mixed Signals: Combinations of Estrogen-Mimicking Chemicals Strongly Distort
Hormone Action
BPA Exposure Effects May Last for Generations
BPA and Chlorine Means Bad News: Modified Forms of Bisphenol A Found to
Alter Hormone Signaling in New, Disturbing Ways
POPs: How are they regulated? Approach in the US: “Innocent until proven guilty”
Industry can introduce any products it wants.
Of the 100,000 synthetic chemicals
on the market today,
only 7% have thoroughly tested
for harmful effects.
Alternative approach:
“Precautionary principle”
Industry cannot introduce a product
until
it is very thoroughly tested and shown
convincingly to be harmless.
Case of DDT
Used 40’s thru 70’s
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Starting in January, toxics-wary consumers can
look for furniture with the “TB 117-2013″ tag, and
ask whether the item has been treated with
flame-retardant chemicals.
Tips to reduce your ED exposure
• Eat fresh food, rather than canned.
• Avoid cash-register receipts.
• Avoid plastics marked with "PC" for polycarbonate, or recycling number 7. Don't
store or cook foood in plastics of any kind, including plastic wrap made from No. 3
plastic.
• Eat less meat, fish, milk, eggs and butter.
• Buy organic produce.
• Choose a water filter that will remove atrazine, perchlorate, lead, arsenic and
other chemicals.
• Avoid personal care products with "fragrance" in the list of ingredients.
• Be sure to consume the recommended amount of iodine, iron, calcium and
Vitamin C.
• Use a vacuum cleaner with a HEPA filter.
• Don't eat fish high on the food chain, like tuna, swordfish and shark.
• Don't use non-stick pans, or products with stain- and water-resistant coatings.
• Don't buy cleaning products or other household chemicals that include the
ingredients 2-butoxyethanol (EGBE) and methoxydiglycol (DEGME).
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In order to control water pollution
We need to understand
The sources of these pollutants:
Point at which they enter a water reservoir
Water pollution: point and non-point sources
Point source: single locations
Non-point source: multiple inputs over larger areas
How does the type of source of the pollution change the approach to solve it?
Example: Cities produce urban runoff and sewage
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Sewage: Point source pollution Easy to identify and control
Water treatment plants
control the discharge
of treated sewage into ocean
But difficult to regulate,
if interest groups
oppose regulations
Example:
LA does full 2nd treatment
and use of biosolids
Orange County
moving to implement
2ndary treatment
San Diego City
does not believe it is necessary
Urban runoff: non point source pollution
Includes water for yards, wash our cars, runoff over
concrete and asphalt
It carries tire shavings, motor oil, exhaust residue,
dog feces, fertilizers, pesticides, cleaning products,
trash and others.
Urban runoff gets collected
by storm drains and enters ocean untreated
Difficult to control
It is the major problem affecting SC’s rivers,
lakes and coasts.
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Ground Water Pollution is a serious problem
From industry, agriculture, urban waste
And leakage of storing tanks
Out of sight – out of mind pollution
Long lasting
What type of source pollution is it?
Solutions for water pollution
In AGRICULTURE:
• Reduce erosion to minimize sediment pollution
• Use fewer or less toxic pesticides
• Use fewer fertilizers
• Properly treat animal waste
From 1995 to 1998,
1,000 spills occurred at livestock feedlots in 10 states
200 manure-related fish kills resulted in the death of
13 million fish.
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Solutions for water pollution
In the INDUSTRIAL and MUNICIPAL sectors:
• Shift to processes that produce less waste
• Shift to less-toxic chemicals and products
• Invest in reducing leaks
• Properly treat wastewater
• Restrict use of pollutants over aquifers
Solutions for water pollution In the RESIDENTIAL sector (what YOU can do):
• Buy phosphorus-free detergents and other
“environmentally friendly” products
• Dispose of hazardous waste properly, not down a drain
•Reduce the use of fertilizers and pesticides on your lawn
•Keep your driveway clean by sweeping rather than hosing it down.
•Fix oil leaks in your car and dispose of used motor oil properly
(never in storm drains!).
•Put your trash in proper receptacles, at the beach and in your hometown.
•Clean up after your pets.
•Water your garden properly