Title: Removal of indicator bacteria, human enteric viruses, Giardia cysts, and Cryptosporidium oocysts at
1Removal of indicator bacteria, human
entericviruses, Giardia cysts, and
Cryptosporidiumoocysts at a large wastewater
primary treatmentfacility
- Presenter Jonas Lindkvist
- Topic Pathogen removal in wastewater treatment
plants - By Pierre Payment, Robert Plante, Patrick
Cejka - Source Science Direct
- Published February 26, 2001
2Introduction
- Montréals waste water treatment plant
- Largest waste water treatment plant in Canada
- Treat waste water from over one million people
including the industry of Montréal - Treats a volume of water representing 50 of the
waste waters treated in Québec. - Can treat 2 billion U.S gallons per day
3Picture of Montréals waste water treatment plant
4- A examination have been done of the plants
ability to remove pathogenic bacteria from
wastewater. - 6 month occurrence study
- May - October
- Samples collected 4 times per week
5Examined pathogens (P) and indicator bacteria (I)
- Human enteric viruses (P)
- Giardia lamblia (P)
- Cryptosporidium parvum (P)
- Clostridium perfringens (P)
- Fecal coliforms (I)
- E.coli (I)
- Fecal streptococci (I)
6Human enteric viruses
- No treatment for diseases caused by these
viruses. - Poliovirus This disease have a effective
vaccine
7Giardia lamblia
- A parasite that is transmitted through water
infected with feces - Colonize small intestine in humans
- Symptom - stomach trouble
- - diarrhea
-
8Cryptosporidium parvum
- Protozoa A single-celled animal
- Cause - intestinal infection with severe
diarrhea - C. Parvum lining the intestinal tract
9Clostridium perfringens
- Occurs in the intestines of humans
- Produce toxin that cause
- - Death (rare)
- - severe illness
- - Intense pain
- - Diarrhea
10E.coli
- The most common bacteria in humans
gastrointestinal tract - Often no symptoms
- Sometimes symptoms as
- - urinary infection
- - diarrhea
11Fecal streptococci and Fecal coliforms
- Indicators of recent fecal pollution because they
are commonly found in human and animal feces - Indicate the possible presence of pathogenic
(disease-causing) bacteria, viruses, and
protozoans that also live in human and animal
digestive systems
12Methods and experimental design
- 3 liters of untreated and treated water was
collected four times per week between May and
october - 2 liters were used for the virus and the
pathogens. 1 liter for bacteriological analysis.
13Methods and experimental design
- Used membrane filtration methods to dilute them.
- Concentrated water were centrifuged at
- 3000 x g for 30 min at 4?C
14Methods and experimental design
- Detection of parasites and viruses
- They did not distinguish between dead and live
parasites - Used immunoflourescence to count the cells.
15Table 1. Indicator bacteria and pathogens at the
Montreal waste water treatment plant before
and after treatment
16Presented results
- Human enteric viruses
- - no removal observed
- Giardia lamblia
- - 76 removed from treatment
- Cryptosporidium parvum
- - 26 removed from treatment
- Clostridium perfringens
- - 51 removed from treatment
- Fecal coliforms
- - 25 removed from treatment
17Presented results
- E.coli
- 12 removed from treatment
- Fecal streptococci
- 29 removed from treatment
-
18Conclusions
- The plant was not efficient at removing indicator
bacteria and pathogens tested - To protect public health additional treatment and
disinfection is recommended.
19Critique
- This report should have been worked on more
before it was released. They should have
explained more about for example methods used,
and also had more headlines. - Methods and equipment were not described well.
- Hard to see results from diagrams
- Dividing up article was done in a bad way with no
structure - Used strange background information in some
parts.
20Questions????