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water pollution presentation

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ARE YOU SWIMMING IN A
SEWER?
Waste Water
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Billions of gallons produced every day
500 million gallons in Boston, MA
950 million gallons in Los Angeles, CA
1.5 billion gallons in NYC
Boston Harbor
• Ten years ago it was one of the most polluted
harbors
• First environmental law in the United States
was passed in Boston in 1656, restricting
butchers from dumping animal parts and other
garbage into the harbor waters
• In the 1660's, Boston Harbor was the major
import harbor from England
Boston Harbor
• In 1796, there were a series of illnesses
breaking out
• The 1863 cholera epidemic lead to a
public cry for improved sewage
• In the latter part of the 1800's, warnings
were posted to not swim in the Boston
Harbor for fear of boils.
Boston Harbor
• They built two sewage treatments plants-in
1889 and 1899 –an improvement but they
still pumped raw sewage into the harbor
• They ignored the Clean Water Act passed by
Congress in 1972
Water Treatment
Primary Treatment
• Large and small debris screened out on
Nut Island
• Waste water sent to Deer Island where
larger particles are allowed to settle outsludge
• Sludge sent to digesters
Water Treatment
Secondary Treatment
• Biological process
• Wastewater and microorganisms are
combined in tanks
• Secondary sludge sent to digesters
• Sludge converted to fertilizer pellets
• Clarified water mixed with bleach
• Declorinated and discharged into bay
How dangerous is the wastewater
that we put in the sea?
Contamination can lead to
detrimental effects in fish and
other species. Shown here is a
fish with tumors.
Municipal Sewage
• Excess nutrients
Excess Nutrients
• Caused by various forms of nitrogen and
phosphates
• Found in fertilizer, plant material,
detergents etc
• Necessary for plant growth
• In excess, leads to excessive growth of
aquatic plants
Municipal Sewage
• Excess nutrients
• Disease carrying bacteria/viruses
Bacteria/Viruses
• Enters water through stormwater drains,
sanitary sewer over flows, failing septic
tanks, runoff from livestock pens, boats that
dump sewage etc
• Test for a few indicator bacteria such as
fecal coliforms and E. coli
Municipal Sewage
• Excess nutrients
• Disease carrying bacteria/viruses
• Toxic chemicals and metals
Toxic Chemical/Metals
• Most dangerous
• Sewage concentrates it
• Many times transformed by natural
processes to more harmful substances
Minamata Disease
• A neurological disorder caused by the
ingestion of large amounts of fish/shellfish
contaminated by methlmercury
• From two industrial effluents in Minamata
and Niigata, Japan
Chisso Factory
• Manufacturer of acetaldehyde- produced
methylmercury as by product
• 1932-started dumping mercury
containing waste
• 1956-Minamata Bay-1st patient with
neurological symptoms of unknown cause
• 1965-similar epidemic in Agano River basin
• Men/women excluding infants affectedsuspected a type of food poisoning
involving fish/shellfish
• Took 12 years to figure out that mercury
was the cause.
Symptoms
• Tremors/spasms/violent convulsions
• Tunnel vision
• Slurred speech/speech and language
disorders
• Sensory disorders of the limbs
• Children born with severe metal retardation
No specific effective therapy
-use mercury eliminators such as
penicillamine and Thiola
Environmental Control
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Stop using mercury
Control effluent
Environmental Restoration
Restrict the intake of fish
New Bedford, MA
• Industrial city along the Northeast US
seaboard
• Largest marine EPA Superfund for PCB
(polychlorinated biphenyls) contamination
• Two electrical capacitor manufacturing
facilities discharged PCB wastes directly into
the harbor and indirectly via discharges to the
city’s sewage system
Have we learned any lessons?
The FDA in 2001 recommended that shark,
swordfish, king mackerel and tilefish not be
eaten by pregnant women and women of
childbearing age who might become pregnant.
It also recommended that nursing mothers and
young children steer clear of these fish.
Recent Events
Pollution 'killing Asia's
dolphins'
Tuesday, March 22, 2005 Posted: 3:40 AM EST (0840 GMT)
A rare Chinese white
dolphin swims in Hong
Kong waters. River
dolphins are particularly at
risk of pollution.
Only 13 of the dolphins were
known to be left in China's Yangtze
River where they once proliferated.
Expelling mercury from
science labs
Schools finding safe alternatives
Sunday, March 6, 2005 Posted: 4:48 PM EST (2148 GMT)
Fire department and
Hazmat teams enter a
Washington high school
after a mercury spill on
March 2.
Great Salt Lake Mercury Levels Alarm
Scientists
Feb. 19, 2005
SALT LAKE CITY (AP) -- Federal scientists studying the Great Salt
Lake have found some of the highest levels of mercury ever
measured anywhere -- prompting concern about some of the
migratory birds that feed on the lake's brine shrimp.
U.S. Geological Survey and Fish and Wildlife Service researchers
were initially gathering information on selenium in the lake, but
decided also to test the samples for mercury.
Concentrations of methylmercury -- the element's most poisonous
form -- exceeded 25 nanograms per liter of water. Fish consumption
warnings have been issued when there was just 1 nanogram per
liter.
"We thought we would find some high levels of methylmercury," said
David Naftz, the USGS research hydrologist who is heading the
Great Salt Lake project, "but not some of the highest (the USGS)
has ever found."
Trace metals leaching through
groundwater from Wildcat Landfill
(shown here) near Dover, DE resulted
in contaminated sediment and surface
waters. NOAA has been working to
clean up this site since 1988.
Have we learned our lessons?
• Pollution of the environment has created a
health hazard for man
• Steps must be taken to control
environmental pollution
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