no slide title - earth...dracunculiasis water and sanitation – critical elements in development -...

Water

Pollution

Water pollution is any chemical, biological, or physical change in

water quality that has a harmful effect on living organisms or

makes water unsuitable for desired uses.

1. disease–causing agents: bacteria, viruses,

protozoa, & parasites;

2. oxygen demanding wastes: organic wastes

that can be decomposed by aerobic bacteria;

3. water–soluble inorganic chemicals: acids,

salts, & compounds with heavy metals;

4. organic chemicals: oil, gasoline, plastics,

pesticides, cleaning solvents, detergents, etc.

Types & Sources of Water Pollution

© Brooks/Cole Publishing Company / ITP

Types & Sources of Water

Pollution cont…

5. sediment: suspended matter, insoluble

particles of soil & other solids; biggest class

of pollution by weight;

6. water–soluble radioactive isotopes:

ionizing radiation sources;

7. genetic pollution: introduction of non–native

species;

8. thermal pollution: heat added to water.

Large populations of bacteria decomposing these wastes

can degrade water quality by depleting dissolved oxygen.

• dissolved oxygen

(DO) is a key indicator

of water quality

Oxygen–Demanding Wastes


Biological Oxygen Demand (BOD)

• BOD: Oxygen is removed from water when organic

matter is consumed by bacteria.

• Low oxygen conditions may kill fish and other organisms.

Sources of organic matter

• Natural inputs-- bogs, swamps, leaf fall, and vegetation

aligning waterways.

• Human inputs-- pulp and paper mills, meat-packing

plants, food processing industries, and wastewater

treatment plants.

• Non-point inputs-- runoff from urban areas, agricultural

areas, and feedlots.

BOD Effects on Water Quality

All streams have some capability to degrade organic waste.

Problems occur when stream is overloaded with biochemical

oxygen-demanding waste.

Degradable/Biodegradable

• Degradable: That can be chemically decomposed: decomposable plastic wastes

• Photodegradable: that the product is decomposed (broken down) by exposure to light

• Biodegradable: Capable of being decomposed by biological agents, especially bacteria: a biodegradable detergent

bss.sfsu.edu/ehines/geog600/

Freshwater%20and%20ocean%20Pollution.ppt

It is easier to control pollution that comes from a distinct source

than pollution that does not come from a distinct source.

• point sources discharge pollutants at specific locations

through pipes, ditches, or sewers (e.g., factories,

sewage treatment plants, mines, oil wells, oil tankers)

• Non-point sources can not be traced to a single site of

discharge (e.g., acid deposition, substances picked up

in runoff, seepage into groundwater)

• nonpoint source water pollution from agriculture is

largest source of water pollution in the U.S. (64% of

pollutants into streams & 57% of pollutants entering

lakes).

Point & Non-point Sources


Water pollution control laws enacted in the

1970s have greatly increased the number &

quality of wastewater treatment plants in the

U.S.

•also improvements in Canada, Japan, &

most western European countries;

• large fish kill & contamination of drinking

water still occur, especially in developing

countries;

• lakes, reservoirs & ponds are more

vulnerable to contamination than streams

because of less mixing & aeration.

Pollution of Streams & Lakes


Biological

magnification of

PCBs

(polychlorinated

biphenyls) results

when

concentrations

increase at

increasing levels

in the food chain.

Pollution of Streams & Lakes


Fig. 20–5 •http://www.epi.state.nc.us/epi/fi

sh/current.html

http://www.epi.state.nc.us/epi/fish/current.html

http://www.epi.state.nc.us/epi/fish/current.html

•For more than 30 years, Ward Transformer, a Superfund site on 11 acres near

Interstate 540 and the Raleigh-Durham Airport, has bled PCBs into dirt and

ditch, woods and stream. The hazardous chemicals polychlorinated

biphenylshave trickled downstream into tributaries including Little Brier Creek

and Brier Creek, flowing into the Brier Creek Reservoir and the popular fishing

spot Lake Crabtree, where it threatens to spill into waterways running through

the Raleigh Greenway.

•PCBs can accumulate in

the leaves and above-

ground parts of plants

and food crops. They are

also taken up into the

bodies of small

organisms and fish. As a

result, people who ingest

fish may be exposed to

PCBs that have

bioaccumulated in the

fish they are ingesting.

•With direct-fired thermal desorption, contaminated soil is placed on a

conveyor belt leading to a kiln that is much like a clothes dryer. Inside, a

flame burns the soil, which then is fed to an afterburner to destroy the PCBs

on site. Gas from the PCB destruction is cooled, passed through a baghouse

to trap contaminated dust, then run through scrubbers to control chlorine, and

finally sent up the stack. The rate of emissions is much higher than those with

indirect-fired thermal desorption, and those gases generally contain some

level of dioxin, a byproduct of burned PCBs and one of the most hazardous

known chemicals.

•Health Effects

•PCBs have been demonstrated to

cause a variety of serious health

effects. PCBs have been shown to

cause cancer and a number of serious

non-cancer health effects in animals,

including effects on the immune

system, reproductive system, nervous

system, and endocrine system.

Studies in humans provide supportive

evidence for the potential

carcinogenicity and non-carcinogenic

effects of PCBs.

http://www.epa.gov/epawaste/hazard/tsd/pcbs/pubs/effects.htm

Diseases Pathogens

• E-coli

• Giardia sp.*

• Hepatitis A and E virus

• Guinea Worm Disease

Waterborne Bacteria

Escherichia coli Vibrio sp. Barbara E. Moore, Ph.D., Department of Biology, University of Texas at San Antonio

• Disease symptoms usually are explosive

emissions from either end of the digestive

tract

• Example – E.coli

http://www.texastmdl.org/presentations/ Pathogen Issues I final.ppt

Waterborne Protozoans

EXAMPLE - Giardia sp.*

*P. Darben

Barbara E. Moore, Ph.D., Department of Biology, University of Texas at San Antonio

• Disease symptoms are usually explosive

emissions from either end of the digestive

tract


Waterborne Human Viruses

Hepatitis A virus Hepatitis E virus

Norwalk virus* Rotavirus*

*F. Williams Barbara E. Moore, Ph.D., Department of Biology, University of Texas at San Antonio


Case Study on Eradicating

Dracunculiasis

Water and Sanitation – Critical Elements in Development - Mike Lee CSU @ Hayward

//FS1/SYS/APES Powerpoint/isis.csuhayward.edu/alss/geography/ mlee/geog2400/2400c15s02.ppt







Guinea Worm Disease

• People have suffered from Guinea Worms for centuries – the “fiery serpent” was mentioned in the bible

• People are infected by drinking water that contain the larvae in a tiny freshwater crustacean called Cyclops

• A year later, larvae mature into 3 feet worms that emerge through skin blisters

• This is such a painful process that men and women can’t work, children can’t attend school









http://www.pmeh.uiowa.edu/fuortes/63111/GUINEA/

The Guinea

Worm grows

down the leg and

its sex organs

appear at the

ankle or on the

foot usually,

bursting when it

senses water,

releasing ova.









• No vaccine for Guinea worm is available.

• People do not seem to build up any resistance and the disease can be reinfected over and over.

• No research is being conducted for any vaccine or cure.

• Worms are removed slowly each day by winding around a stick.

http://www.pmeh.uiowa.edu/fuortes/63111/GUINEA/ Water and Sanitation – Critical Elements in Development - Mike Lee CSU @ Hayward








Heavy Metals

• Metallic elements having a density greater than 5 g/cm3

• Most are extremely toxic

– Water soluble

– Readily absorbed into plant or animal tissue

• Bioconcentrate

– Combine with biomolecules

• Proteins

• Nucleic acids Heavy Metals by Dr. Jena Hamra

//FS1/SYS/APES Powerpoint/faculty.tamu-commerce.edu/jhamra/Environmental_Toxicology/ EnvTox Metals.ppt

Sources of Heavy Metals

• Natural

– Redistributed by geologic and

biologic cycles

• Industrial

• Burning of fossil fuels

• Environmental pollution

Heavy Metals by Dr. Jena Hamra

//FS1/SYS/APES Powerpoint/faculty.tamu-commerce.edu/jhamra/Environmental_Toxicology/ EnvTox Metals.ppt

• Lead: leaded gasoline, tire wear, lubricating oil

and grease, bearing wear

• Zinc: tire wear, motor oil, grease, brake

emissions, corrosion of galvanized parts

• Iron: auto body rust, engine parts

• Copper: bearing wear, engine parts, brake

emissions

• Cadmium: tire wear, fuel burning, batteries

• Chromium: air conditioning coolants, engine

parts, brake emissions

• Nickel: diesel fuel and gasoline, lubricating oil,

brake emissions

• Aluminum: auto body corrosion

Selected Pollutants: Nutrients

Phosphorus and nitrogen are the major concerns

Sources:

•Human, animal (e.g., Hog Farms), and industrial waste

•Storm water

•Soil erosion

•Excessive use of fertilizers for crops, lawns, and home

gardens

Natural nutrient

enrichment of

lakes is called

eutrophication.

Cultural

eutrophication

results when

human activities

accelerate the

input of nutrients

to a lake.

Pollution of Lakes


Fig. 20–6

Selected Pollutants: Nutrients

1. Eutrophication is characterized

by rapid increase in plant life. An

example is the algae bloom shown

here.

2. Algae blooms block sunlight so

plants below die.

3. Decomposition of dead plants

consumes oxygen.

4. Low oxygen conditions may kill

fish etc.

•Aesthetics (color, clarity, smell)

•Uptake and release of toxics

High nutrient concentrations can cause Eutrophication (“well-

fed” in Greek) of water bodies

The Great Lakes basin

contain at least 95% of

the fresh surface water

in the U.S. & 20% of the

world's fresh surface

water. In the 1960s

many areas of the

Great Lakes (in

particular Lake Erie)

suffered severe cultural

eutrophication. Since

1972, a $20 billion

pollution–control

program improved

water quality.

Case Study: Great Lakes


Fig. 20–7

Dead zones - large scale, too!

•Due to Agricultural runoff into Mississippi River

(Midwest farms)

•Sport fishing, shrimp, crab, oyster fisheries

devastated

•20,000 square miles (area of New Jersey)

Erosion

Sediment (clay, silt) is the #1 source of water pollution. Bare soil easily washes into storm drains and streams, clouding the water and suffocating aquatic life.

Effects of Sediment Loading

• Destruction of spawning beds

• Absorption and transport of other pollutants

• Reduced light penetration, aquatic vegetation

• Greater nutrients loadings, oxygen demand

• Interference with navigation, flood control,

recreation, industry

pH Effects on Wildlife

• Generally, the young of most species are

more sensitive to environmental conditions

than adults

• At pH 5, most fish eggs cannot hatch

• At lower pH levels, some adult fish die

• Some acid lakes

have no fish

http://www.epa.gov/airmarkets/acidrain/ effects/surfacewater.html

Thermal Pollution • occurs when water is withdrawn, used for

cooling purposes, and then heated water is

returned to its original source

• An increase in temperature, even a few

degrees, may significantly alter some

aquatic ecosystems

• SOURCES – industry, fossil fuel power

plants. nuclear power plants

Hydrilla: Non-native Aquatic Plant

• Dense mats alter water quality

– raising pH

– decreasing oxygen under the mats

– increasing temperature

– stagnant water

– good breeding grounds for mosquitoes

• Hydrilla will grow with less light and fewer

nutrients, and can out compete other native and non-native plant

• Fish populations are negatively affected if hydrilla exceeds 30-40% coverage of the lake



•Invasive Species

Out–of–sight pollution of groundwater is a greater

threat to humans than much of the more visible

surface water pollution.

• much of groundwater is renewed slowly, such that

pollution lingers for long periods of time;

• crude estimates indicate that up to 25% of usable

groundwater in the United States is contaminated;

• extremely difficult to cleanup contaminated

groundwater; prevention of contamination more

effective;

• pumping groundwater to the surface, purifying the

water, & returning it to the aquifer is main approach, but

costs are very high.

Groundwater Pollution


Principal

sources of

groundwater

contamination

in the United

States.



Fig. 20–13

Ways to prevent contamination of groundwater

include the following:

• in general, reduce sources of water pollution that feed

into the aquifer;

• monitor aquifers near landfills & underground storage

tanks;

• require leak detection systems & liability insurance

for existing & new underground tanks that store

hazardous liquids;

• ban or more strictly regulate disposal of hazardous

wastes in deep injection wells & landfills;

• store hazardous liquids aboveground with more

safeguards;



Means for preventing, reducing, & cleanup of water

pollution include both legal & technological

approaches.

• Legislation: Clean Water Act (1972, ammended 1977) &

Water Quality Act (1983) form basis of water pollution

legislation in U.S.;

- main goals of Clean Water Act

- make U.S. surface waters safe for fishing &

swimming by 1983

- to restore the chemical, physical & biological

integrity of waters;

- progress has been made, but goals not met;

• technology: installation of septic tanks, sewage treatment

plants can greatly decrease water pollution;

• legal & technological approaches most effective for nonpoint

pollution sources.

Dealing with Water Pollution


Septic tank

systems are

used to dispose

of sewge &

wastewater in

rural & suburban

areas. This

system traps

greases & large

solids &

discharges the

remaining wastes

over a large

drainage field.



Fig. 20–10

Primary sewage

treatment involves

screens & settling

tanks to remove

solids from

sewage.

Secondary

sewage treatment

uses biological

processes to break

down

biodegradable,

oxygen–

demanding

wastes.



Fig. 20–11

Advanced

sewage

treatment uses

one or more

processes to

remove specific

pollutants from

sewage.



Fig. 20–12

What can we do about water pollution from nonpoint

sources?

• agriculture is main nonpoint source of water pollution;

• changing farming practices to reduce runoff from

fertilizer, pesticides, & livestock, as well as to reduce

soil erosion;

• non–farm use of fertilizers & pesticides (golf course,

lawns, & public lands) are another major nonpoint

source, & can be similarly controlled.



Much of the world's drinking water is contaminated

& poses serious health threats.

• currently most drinking water is purified by storage in

a reservoir, where suspended matter settles out, &

then treated by sand filters, activated charcoal, &

addition of chlorine;

• U.S. Safe Drinking Water Act of 1974 requires EPA

to establish national drinking water standards;

currently efforts by industry to weaken the standards;

• many individuals turning to bottled water & home

filters; bottled water is often more contaminated than

tap water.

Drinking Water Quality


• Coastal areas most impacted – especially wetlands and

estuaries, coral reefs, and mangrove swamps

• Half of world's population lives within 100 km (60

miles) of oceans and 14 of 15 largest cities coastal

• About 35% of U.S. municipal sewage discharged

virtually untreated in ocean waters

• Dumping of industrial waste directly into ocean off U.S.

coasts stopped, but many countries still dump large

quantities of toxic substances

• Ocean is the ultimate repository of waste

Ocean Pollution

© Brooks/Cole Publishing Company / ITP Water

Resources and Water Pollution by Paul Rich

http://www.sci.sdsu.edu/classes/iscor310/iscor310_archive/Chapter_12_Lecture/mi0212-conc0112.ppt



Pollution in Coastal Waters

• Coastal waters especially are highly affected by pollution because they are:

– Heavily used

– Close to sources of pollution

– Shallow-water bodies

– Not as well circulated as the open ocean

• Coastal pollution is made up of ocean pollution and ocean debris



Main Types of Ocean Pollution • Petroleum (oil)

• Sewage sludge

• DDT and PCBs

• Mercury

• Point source: clearly discernable in terms of origin (municipal sewage outfall, oil tanker spills, offshore oil well blowouts)

• Non-point-source pollution: ill-defined or diffused sources, runoff (harbors and marinas, TBT, powerboat pollution, invasive species, agriculture, forestry, urban runoff, ocean debris, air pollution, noise pollution, dredging



Ocean Pollution: Petroleum

• Oil spills can

be caused by:

– Tanker

accidents

– Intentional

dumping

– Drilling/

pumping

operations



• Volatile Organics Compounds immediately kill many of

the aquatic organisms (especially plankton and larvae) and

contaminate fish

• Floating oil coats birds and ocean mammal; destroys

natural insulation and buoyancy and causes deaths

• Heavy oil sinks to ocean bottom and washes into estuaries

where it contaminates crabs, oysters, mussels, clams, etc.

• Oil slicks on beaches harm intertidal life and cause

economic losses to tourism and fishing industries

Effects of Oil Spills







• When oil washes up

at a beach, it can

negatively affect the

ocean environment

• Oil can coat ocean

organisms and

render their

insulating fur or

feathers useless Oil on the beach from the Exxon Valdez oil spill,

Alaska bss.sfsu.edu/ehines/geog600/


Ocean Pollution:

Petroleum

• Petroleum is biodegradable

• Many pollution experts

consider oil to be among

the least damaging ocean

pollutants

• Data from the 1989 Exxon

Valdez oil spill shows the

recovery of key organisms




Various

processes act

to break up

and degrade

oil in the

ocean

environment



• March 24, 1989, tanker

in Prince William

Sound, Alaska, worst oil

spill in U.S. waters

• Coated 1,600 of

shoreline, killed wildlife,

and caused serious

contamination

• Exxon spent $2.2 billion

on direct cleanup + $1

billion fines and

damages; another $5

billion being appealed

Case Study: Exxon Valdez Oil Spill






Exxon Valdez only #53????



Ocean Pollution: Sewage Sludge

• Sewage sludge is the semisolid material that remains after sewage treatment

• Much sewage sludge was dumped offshore until laws restricted sewage dumping



Ocean Pollution: DDT

• DDT was a widely used pesticide that

became concentrated in ocean fish

• DDT caused brown pelicans and ospreys to

produce thin egg shells

• Worldwide, DDT has been banned from

agricultural use but is still found in

developing countries…



Ocean Pollution: PCBs

• PCBs are industrial chemicals used as liquid

coolants and insulation in industrial

equipment such as power transformers

• PCBs enter the ocean environment through

leaks and from discarded equipment

• PCBs can accumulate in animal tissues and

affect reproduction



Ocean Pollution: Mercury and

Minamata Disease • Mercury has many

industrial uses but is

extremely toxic

• A chemical plant

released large

quantities of mercury

into Minamata Bay,

Japan

• Residents who ate

highly contaminated

fish suffered

neurological disease

and birth disorders



• Largest

estuary in U.S.

• Severely

degraded by

water

pollution from

6 states

• Deposition of

air pollutants

Case Study: Chesapeake Bay

Fig. 12–24






Ocean Pollution: Point Source

• Originate from

municipal and industrial

facilities

• Bypasses and overflows

from municipal sewage

systems

• Oil tanker spills and

offshore oil well

blowouts



Ocean Pollution: Non-Point Source

• Non-point-source

pollution comes from

material washed down

storm drains as

“poison runoff”

• Includes fertilizers,

pesticides, road oil,

and trash bss.sfsu.edu/ehines/geog600/


Plastic in the Ocean Environment

• Plastic:

– Either does not

biodegrade or not

in human time…

– Floats

– Has high strength

– Is ingested by and

entangles ocean

animals bss.sfsu.edu/ehines/geog600/


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