cities, rivers, wastes and biological pollution rivers and cities thames tiber venice london rome
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Roman Aqueducts
255 miles of aqueducts
Stone, lined with cement
Water distributed throughlead pipes and logs
144 publiclatrines
1 million people
-lead pipes
-lead acetate
sugar of lead sweetener for wine
Lead (Plumbum)
Caligula, Nero, Commodus, Julius Caesar, Caesar Augustus
Domitian’s Fountain of leaded wine
Saturnine: an individual whose temperament has become uniformly gloomy and cynical.
Saturn: the deity of lead
Father of all metals
Possible cause of the dementia which affected Roman Emperors and Citizens.
Possible contributing factor to the Fall of the Roman empire
After the Fall
drinking water hauled in from springs outside the city limits
500 to 1500 A.D.
City wells fouled
Diverted WealthNeglect of infrastructure
reduced the population of the city of Rome from its high of over 1 million in ancient times to considerably less in the medieval era, reaching as low as 30,000
17th to 19th Centuries
Cesspools/outhousesLeaching
270,000 cubic meters of manure (Paris, 1780)
Offensive Odor And taste.
Deterioration of wells
Growth of Urban Populations
Graveyards in City Limits
“rank and offensive mold,mixed with broken bones andfragments of coffins”
Basil Hall, 1820
New York’s Trinity Church held 160,000 graves by 1830.
“Nearly every residence had a cesspit beneath the floors. In the best of homes the nauseating stench permeated the most elegant parlor.”
To river or street
Cesspits
London's sewers were open ditches sloped slightly to drain human wastes toward the River Thames
When cesspits filled to overflow, they were built to drain to the street by means of a crudely built culvert to a partially open sewer trench in the center of the street
Cesspits
Night Soil
Methane (CH4)
CH4 + 2O2 = CO2 + 2H2Olamps
Cesspits and Night Soil
Methanogenesis is the final step in the decay of organic matter under anoxic conditions
c.a. 1850
Southampton, 1849: "Explosions occurred in two separate locations where the men had the skin peeled off their faces and their hair singed”.
Anaerobic organisms: Exist in low oxygen
John Harrington1596
The Age of the Toilet
Alexander Cummings1775
19th Century
Not widely adopted until the mid to late 1800s
Thomas Crapper1866
By 1885, Boston had 100,000 toilets and thousands ofmiles of pipe carrying wastewater to rivers.
Effectively marketed the toilet
1859 Suspension of British Parliament
1861 Typhoid Epidemic
Toilets, Cesspools, Wastes and Urbanization
Connected with contaminated water
Thames River: mid-1800s
Wastewater to Rivers
Extra Credit:
1. The inventor of the toilet ___________________________
2. Built over 255 miles of aqueducts ____________________
3. The first sewer and water systems were built when?
4. Metal that may have contributed to dementia of Romans.
The World Health Organization indicates that every year more than 3.4 million people die as a result of water related diseases, making it the leading cause of disease and death around the world.
Most of the victims are young children, the vast majority of whom die of illnesses caused by organisms that thrive in water sources contaminated by raw sewage.
DiseasesResponsible pathogen
Route of exposure
Mode of transmission
Cholera Vibrio cholerae bacteria
gastro-intestinal
sewage, often waterborne
Botulism Clostridium botulinum bacteria
gastro-intestinal
food/water borne; can grow in food
Typhoid Salmonella typhi bacteria
gastro-intestinal
water/food borne
Hepatitis A Hepatitis A virus gastro-intestinal
water/food borne
Dysentery Shigella dysenteriae bacteria or Entamoeba histolytica amoeba
gastro-intestinal
food/water
Cryptosporidiosis Cryptosporidium parvum protozoa
gastro-intestinal
waterborne; resists chlorine
Polio polioviruses gastro-intestinal
exposure to untreated sewage; may also be waterborne
Giardia Giardia lamblia protozoa
gastro-intestinal
waterborne
Typhoid
Typhoid fever is an illness caused by thebacterium Salmonella Typhi and is transmitted by ingestion of food or water contaminated with feces from an infected person
1837, 1860-1865
186,000 people
The worst year was 1891, when the typhoid death rate was 174 per 100,000 persons
Cholera
Vibrio cholerae Occurs through ingesting food or water which is contaminated with cholera vibrios
In its most severe forms, cholera is one of the most rapidly fatal illnesses known
Intestinal disease
Shock from dehydration can occur in 4 to 12 hours
death within 18 hours to several days
8 major outbreaks from 1816 to 1896 affecting mostly Europe and N. America
1852-1860 - Third cholera pandemic mainly affected Russia, with over a million deaths
Cholera in the U.S.
Croton Aqueduct System50 miles of aqueduct
Epidemic of 1832 killed over 6,500 people in London and 3500 in NY
ORT solution contains:
sodium chloride (NaCl)trisodium citrate dehydratepotassium chloride (KCl)glucose
Intravenous Fluid Therapy
mortality rate of cholera dropped from 70% to 40%
1831
Sodium chloride (NaCl)Citric acidPotassium phosphateglucose
Gatorade
Treatment: Rehydration Therapy
Oral Rehydration Therapy (1960s)
The Indo-Pakistani War of 1971 – mortality rate of 3%
Currently, WHO recommends a 3-day, 12-dose course ofantibiotic treatment with either tetracycline or erythromycin
50% mortality rate among its healthy adult victims
"Cholera was a scourge not of mankind but of the sinner." Bernhard J. Stern, Society and Medical Progress (1941)
Cause of Disease
Miasma and Night Air
Doors and windows of homes and factories were sealed shut at sunset.
A poisonous vapor or mist that is filled with particles from decomposed matter (miasmata) that could cause illnesses and is identifiable by its nasty, foul smell
Theory of used to explain thespread of disease in London and Paris
The Microscope
“people had a dreadfulapprehension of breedingbullfrogs inwardly.”
1880: Pasteur published book on germ theory
Anton van Leeuwenhoek: first microbiologist
Revolutionized knowledge of the causes of disease
Theodor Escherich 1886
1/3 weight of average uninfected human waste
Greatest impacton municipal water
systems and water treatment.
E. coli
Discovery of coliform bacteria
Most forms of e. coli are harmless
Total Coliforms (including fecal coliform
and E. Coli)
Not necessarily a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present
Coliforms are naturally present in the environment; fecal coliforms only come from human and animal fecal waste.
Biological pollution
Drinking Water MCL = no more than 5.0% total samples coliform-positive in a month
Standards based on presence or absence
Freshwater Standard: ~200 units/100 mL
Initial Forms of Water Treatment
Removal of Suspended Solids
Flocculation Sand filtration
Flocculation – bringing together of high numbersof small particles to create larger particles whichsettle out of water quickly.
Suspended Organic and inorganic particles
Higher turbidity levels are often associated with higher levels of viruses, parasites and bacteria.
Turbidity
Suspended particles often function as a habitat for microorganisms
Turbidity is caused by the suspensionof very small particles in water.
Settling Velocity proportional to diameter squared
Small particles settle slowlyLarge particles settle quickly
Many of the particles that cause turbiditycarry a negative electrical charge.
Flocculation
- charge
- charge
- charge
Al3+
Al3+Al3+
Small organic andInorganic particles
Settling rate of particles is proportional to the square of the diameter
Small particles settle slowly, large particle settle quickly from water
Small, Suspended Particles Flocculated particlesContaminants, pathogens
Clear Water
Al3+
Flocculation
Filtration
solidsWaterparticles
Clearer Water
Fast Slow
0.4 m/hour 21 m/hour
Physical straining
Particles larger than the pore
spaces between the sand grains are trapped
Particles smaller than the spaces between sand grains are trapped
Antagonistic bacteria destroyPathogenic bacteria
Physical/ biological straining
• gaseous chlorine• sodium hypochlorite• calcium hypochlorite
Common chemical bleaches include household "chlorine bleach", a solution of approximately 3-6% sodium hypochlorite (NaClO)
Chlorination
A 12% solution is widely used in waterworks for the chlorination of water and a 15% solution is more commonly used for disinfection of waste water in treatment plants.
High-test hypochlorite (HTH) is sold for chlorination of swimming pools and contains approximately 30% calcium hypochlorite.
hypochlorous acid (HOCl) and hypochlorite ion (OCl-).
Destroys cellenzymes
Chlorine Disinfection
hypochlorous acid (HOCl)is responsible for the disinfecting power.
Low pH favors high levelsof HOCl over OCl-
Penetrates bacterial cell
Bacterial death is rapid
NaOCl = Na+ + OCl-
Low pH High pH
The intersection of Cambridge and Broad Street, up to 500 deaths from
Cholera occurred within 10 days
The first known uses of chlorine for water disinfection was by John Snowin 1854, when he attempted to disinfect the Broad Street Pump water supply
Applied to municipal water systems in 1909
Cholera and Chlorine
public well had been dug only three feet from an old cesspit
Chlorination
Chlorine is currently employed by over 98 percent of all U.S. water utilities that disinfect drinking water