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What Lives In Your Water? MdBioLab Activity. Basic Learning Goals Students will understand the connection between water quality and – Economics of Maryland.

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Presentation on theme: "What Lives In Your Water? MdBioLab Activity. Basic Learning Goals Students will understand the connection between water quality and – Economics of Maryland."— Presentation transcript:

1 What Lives In Your Water? MdBioLab Activity

2 Basic Learning Goals Students will understand the connection between water quality and – Economics of Maryland Fishing Tourism Students will learn laboratory techniques identical to those used by EPA and scientists

3 Water cycle Conceptualization of the water cycle. Source: USGCRP website

4 Stream Orders

5 Stream Length in Mid-Atlantic

6 Chesapeake Bay Watershed

7 Chesapeake Bay Sub- watersheds

8 Why Should I Worry? Cholera is a huge killer worldwide – Almost nonexistent in the US due to our water treatment policies – Kills millions of people every year in the developing world 1915

9 Cholera Outbreaks

10 Vibrio spp in the Chesapeake Bay Cholera caused by bacteria Vibrio cholerae Vibrio infect cuts – “hand swollen to the size of a catchers mitt” Infected shellfish cause GI illness Public health websites suggest to protect yourself against infection: – Avoid swimming 48 hours after any heavy rainfall. – Do not swim with an open cut or wound. – If you get cut while in the water, wash it thoroughly and cover with a waterproof bandage. – Try not to swallow water while swimming. Chesapeake Bay Foundation Bad Water 2009

11 Fecal Bacteria “Where do the bacteria come from? There are about 180 failing septic tanks in the Severn River’s suburbanized watershed, according to the Maryland Department of the Environment (MDE). But a far more significant source of bacteria in the river is pet waste, which produces an estimated 69 percent of the E. coli bacteria in Voith’s section of the Severn River, with wildlife contributing 24 percent, livestock three percent, and humans three percent, according to an April 2008 MDE analysis of pollution in the Severn River. About 41 percent of dog owners in the area admit they do not pick up after their animals most of the time, the report says. “ Chesapeake Bay Foundation Bad Water 2009 Disgusting Picture Warning

12 Sources of Fecal Pollution

13 Sources of Fecal Pollution static.gotpetsonline.com/pictures-gallery/dog-pictures-breeders-puppies-rescue/english-shepherd- dog-pictures-breeders-puppies-rescue/pictures/english-shepherd-dog-0003.jpg

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15 One Member of the GI Microflora Enterococcus faecalis – Part of normal flora of all mammals and birds – About 10M Enterococci per gram of human feces. – Gram-positive cocci, facultative anaerobe – Tolerate a wide range of growth conditions including salt and oxygen Enterococcus faecalis infecting lung tissue. Source: Wikipedia

16 Opportunistic pathogen Can cause: – Bladder infections – Endocarditis (infection of heart lining) – Bacteremia (bacteria in blood) – Peritonitis (infection in abdominal cavity) – Meningitis (brain infection) Most cases are hospital-acquired (“nosocomial”) infections Hard to treat – Naturally antibiotic resistant to penicillins – Acquired resistance to many other antibiotics

17 E. Faecalis is a Good Indicator Organism in the Environment Stays alive but doesn’t grow in environment So… numbers stay constant So…counts are representative of volume of pollution sources Scanning Electron Micrograph of Enterococcus faecalis. Sources: CDC Public Health Image Library (PHIL), Photo by Janice Haney Carr

18 Culturing Bacteria in the Lab We create the optimal growth conditions – Temperature – Nutrients – pH Selective media – Contains chemicals that only allow one species to grow Example of bacterial growth on selective media. Photo courtesy of Hornor Lab, Anne Arundel Community College, Arnold, MD.

19 Water Does Not Have To Look Dirty To Be Dangerous!!

20 LAB ACTIVITIES

21 Our Activity Step 1- Collect water samples – Field trip or Homework Students should work in pairs Will require a “collection kit” – Clean plastic bottles – Gloves – Ziplocs for ice and containment of sample

22 Our Activity Step 2- Filter water samples and culture overnight – 2 different volumes 10 ml 100 ml Allows for best opportunity to get a countable plate of colonies

23 Our Activity Step 3- (Next Day) Count Colonies Example of bacterial growth on selective media. Photo courtesy of Hornor Lab, Anne Arundel Community College, Arnold, MD.

24 Equipment Setup Completely assembled filtration apparatus Water samples in ice bucket Field data sheet Sterile 10 ml syringe Beaker with ethanol holding forceps Sterile paper filter

25 Sterile Technique Forceps removed from ethanol, flamed THEN handed to students

26 Place Filter 1 Peel cover off filter (best done by instructor or partner) Grab edge with sterilized forceps

27 Place Filter 2 Place paper filter grid side up on top of metal screen Paper must completely cover screen to get proper filtration

28 Reassemble Filtration Apparatus Place filter funnel on top of paper filter Clamp glassware in place

29 10 ml Sample Wet filter with 10 ml sterile, distilled water – Water removes static from syringe When the water has suctioned through filter, apply 10 ml of water sample to filter

30 Wash Filter Funnel With clean syringe, wash the sides of the funnel to get any splashes

31 Remove Filter Unclamp filter funnel Flame forceps Grab edge of filter and break vacuum seal

32 Place on Plate Hold plate tilted downward and away Place filter at bottom edge of plate Roll onto media to minimize bubbles Cover and incubate 24 hrs

33 Repeat for 100 ml Place new filter on filtration apparatus Wet filter and suction through Pour 100 ml into funnel Wash sides of funnel Place filter on media

34 After Incubation This is what the students will see after a 24 hour incubation at 41˚C (chicken body temperature) Left-hand plates came from Patuxent River Right-hand plates came from Warehouse Creek off South River Top plates are 10 ml, bottom plates are 100ml samples

35 POST-LAB ACTIVITIES

36 Reporting Results

37 Land Use Impervious Surface Farming

38 Civic Engagement Opportunities Information can be reported to local water quality monitoring agencies Community Associations to encourage picking up after pets Service projects to fence streams from livestock

39 Curriculum Materials Provided at MdBioLab Website Instructor’s Manual – Biomedical – Environmental Science Student Handout Field Data Collection Sheet Powerpoint Slides (with speakers notes) – The ones shown today – A set to show to students with a Biomedical focus – A set to show to students with an Environmental Science focus


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