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ARE YOU SWIMMING IN A SEWER? Waste Water • • • • 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 • • • • 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