EESA10H3 Lecture Notes - Lecture 3: Coliform Bacteria, Water Scarcity, Escherichia Coli
23 May 2018
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Department
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Professor
EESA10 – Lecture 3: Waterborne Hazards & Human Health
Liquid Natural Capital
Drinking water
o Annual reports on local drinking water quality – naturally pure water & distilled water
o Natural content of minerals found in water
o Surface water – in urban areas
Rivers
Lakes
Springs
o Ground water – in rural areas
Wells
Earth = water planet; covers 71% of Earth’s surface
o Mostly salt water – sculpts earth’s surface + moderates climate
o No species can live w.out water
o Removes + dilutes wastes & pollutants
WORLD PROBLEMS:
1. Quantity of water
a. Some areas have lots of water but largest rivers are far from agricultural/pop. centers ;
therefore, need to invest a lot to transport it.
i. TORONTOlake Ontario
b. Lots of precipitation arrives during short period but cannot be collected + stores
(conservation of water for ‘dry’ areas/events)
c. USE about 54% of world’s reliable runoff of surface water (by 2025, could be using 70-
90%) – 85% not returned back
i. USAGE OF freshwater:
1. Canada - most used in power plant cooling, in household usage mainly
in showers/baths, toilet, laundry, kitchen/drinking, cleaning..
2. USA – most
3. China – agriculture purposes
ii.
d. WITHDRAWAL – total amount of water removed from rice/lake/aquifer for any purpose
i. Some may be returned to source for reuse but not all the time
ii. Some lakes + rivers shrink/disappear
2. Quality of water
a. Salt water = not readily available for consumption problem b/c most organisms need
freshwater.
b. Ground water = not readily avail; need to drill and excavate
c. Readily available freshwater in lakes/river (small percentage)
i. STRESS on world’s major river basins
1. Water stress < 1700 cubic meters/year/person
2. Water scarcity < 1000 cubic meters/year/person
d. Hydrological Poverty – 1 in 6 don’t have reg. access to clean water (doesn’t matter so
much on income – more on water QUANTITY) . Diarrhea kills over 2 million children
annually
Quality is dependent of
o Water pH
o Hardness
o Color
o Turbidity
o Taste/Odor
o Microbes & Chemicals
CONTAMINANTS in drinking water
1. Microbes
a. Fecal Coliform & E.coli bacteria – contamination w. human+animal wastes, diarrhea,
cramps, nausea, headaches, renal failure, coagulation disorder
i. Fecal coliform test:
This test indicates the likely presence of disease-causing agents in water. A
sample is first passed through a filtering apparatus.
A. The filter disk is then placed on a medium that support coliform bacteria for
24hours.
B. After incubation, the number of bacterial colonies is counted. Each colony of
E.coli arose from a single coliform bacterium in the original water sample
ii. CASE STUDY – Walkerton example (E.coli)
Pipes contained biofilmand a scanning electron micrograph of the surface of a
pipe containing bacteria, isolated from Walkerton during the investigation in
2000.
b. Salmonella typhi – typhoid fever (high fever, abdominal pain, constipation)
c. Shigella sp. – more severe abdominal cramping w/blood + mucus in stool
d. Vibrio Cholerae – life threatening, rice-water stools
e. Norwalk viruses, enteroviruses, adenoviruses – diarrheal illness
f. Hepatitis A – liver inflammation
g. Cryptosporidium – parasite that enters lacks and rivers thru. Sewage + animal wastes
h. Giardia lamblia – enters lakes +rivers thru. Sewage + animal wastes, diarrhea, vomiting,
cramps
2. Radionuclides
Alpha, Beta/photon emitters ; combined radium 226/228 (radon gas, radium) damage to DNA,
increase risk of getting cancer
Document Summary
Eesa10 lecture 3: waterborne hazards & human health. Drinking water: annual reports on local drinking water quality naturally pure water & distilled water, natural content of minerals found in water, surface water in urban areas. Springs: ground water in rural areas. Earth = water planet; covers 71% of earth(cid:859)s surface: mostly salt water sculpts earth(cid:859)s surface + moderates climate, no species can live w. out water, removes + dilutes wastes & pollutants. Quality is dependent of: water ph, hardness, color, turbidity, taste/odor, microbes & chemicals. Contaminants in drinking water: microbes, fecal coliform & e. coli bacteria contamination w. human+animal wastes, diarrhea, cramps, nausea, headaches, renal failure, coagulation disorder, fecal coliform test: This test indicates the likely presence of disease-causing agents in water. A sample is first passed through a filtering apparatus: the filter disk is then placed on a medium that support coliform bacteria for. 24hours: after incubation, the number of bacterial colonies is counted.
