Bacteriological Indicators of Water Pollution:
"In 1885, T. Escherich discovered a bacterial species that was present almost universally in human fecal material. These bacteria not only occurred in high densities but frequently were associated with the pathogenic typhoid bacillus ( Salmonella typhi ). Escherich's bacteria were named Escherichia coli . in 1895 by Migula. Today we have learned that there is a heterogeneous complex of bacterial species in human waste. " Select one: True False
True
A bacteriological indicator is an organism that if detected in a water sample, indicates contamination has/may have occurred. It can originate from human, bird, and wild animal waste. True False
True
HACH HANDOUT INDICATOR ORGANISMS "The World Health Organization has defined coliforms as any rod-shaped, non-spore-forming, gram-negative bacteria capable of growth in the presence of bile salts or other surface-active agents. Continuing, the definition states that coliforms are cytochrome-oxidase negative and able to ferment lactose at either 35 or 37 °C with the production of acid, gas, and aldehyde within 24 to 48 hours." Select one: True False
True
Review past lecture notes to answer the following question. There are four major groups of organisms in the water industry: bacteria, protozoa, metazoan, and viruses. Bacteria are small single celled organisms (can live in extreme conditions, are 5-100 micrometers in size). Protozoa (Giardia and Cryptosporidium) are larger then bacteria and are single celled organisms. Metazoa are composed of more then one cell. Viruses are extremely small and are parasitic (they need a host cell to reproduce). True False
True
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT "Pathogens cause disease. Enteric diseases are intestinal and opportunistic diseases effect people when their resistance is lowered. Giardia and Cryptosporidum are protozoa that are resistant to chlorination." Select one: True False
True
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT "The drinking water standards for the USEPA— Bacteriological Ambient Water Quality Criteria for Marine and Fresh Recreational Waters—specifies the following standards: for fresh water, E. coli count ≤126/100 mL, enterococci ≤33/100 mL; for marine water, enterococci ≤35/100 mL. Remember that these values represent AVERAGES of 5 samples collected in a 30 day time-span. Since most of you are collecting one grab sample the Guidelines are as follows for recreational water. DRINKING WATER & RECREATIONAL WATER QUALITY: Microbiological Criteria Primary Contact Recreational Water • Fecal coliforms not to exceed 500/100 mL at any time. Secondary Contact Recreational Water • Fecal coliforms not to exceed 800/100 mL at any time. Freshwater designated beach areas (Primary Contact) • Enterococcus maximum allowable 61/100 mL. • E. coli maximum allowable 235/100 mL. Freshwater moderate contact (Secondary Contact) • Enterococcus maximum allowable 89/100 mL. • E. coli maximum allowable 298/100 mL. True False
True
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT A fecal coliform is a thermotolerant total coliform bacteria capable of growth with gas and acid production at 44.5 degrees Celsius. True False
True
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT Elevated total coliforms can occur via a false positive from non fecal organisms such as Klebsiella and Citrobacter. Additionally, some pathogens (Salmonella and Shigella) can live as long or longer than a total coliform. This can lead to rare causes of outbreak (worldwide these two bacteria kill ~1.5 million people (Thats about the size of the city of Portland and all metro areas!) True False
True
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT "The total coliform group is the most inclusive indicator classification ( and contamination indicated by the presence of total coliforms is indicative of inadequate disinfection of drinking water. Therefore, in the United States and most other developed countries the microbiological quality standards for drinking water are based on the measurement of the total coliform population." True False
True
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT "The incubation temperature of the fecal test has been modified to 44.5 °C. Today the accepted definition of fecal coliform bacteria is: thermotolerant total coliform bacteria capable of growth with acid and gas production at 44.5 ± 0.2 °C. The bacteria included in this group are predominantly E. coli, Citrobacter freundii and Klebsiella pneumoniae." Select one: True False
True
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT ) What year did Snow and Budd determine that typhoid fever and cholera were related to fecal contamination of drinking water? Select one: a. 1985 b. 1898 c. 1855 d. 1931
1855
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT E. coli, Klebsiella, Enterobacter, Proteus, Providencia, and Serratia marcescens are responsible for ____% of hospital realted infecitons. a. 50 b. 25 c. 15 d. 10
50
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT Which of the following are used as inhibitory substances (inhibit growth of 70% of injured coliforms) in m-Endo broth? a. sodium deoxycholate b. sodium lauryl sulfate c. both A and B are correct
both A and B are correct
Which of the following bacteria are considered part of the coliform group? Select one: a. Streptococcus b. Lactobacillus c. Staphylococcus d. Proteus and Pseudomonas e. All of the above Correct
All of the above
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT When doing membrane filtrations typical colonies are counted and reported as number of bacteria per liter of sample Select one: True False
False
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT When Standard Methods-approved m-FC broth or agar is used, fecal coliforms growing on the membrane form an acid that reacts with aniline blue (a dye) to produce a blue color. In this test, a suitably prepared membrane filter is placed on a pad saturated with m-FC and incubated for 18 hours at 44.5 ± 0.2 °C. True False
False
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT The test for E. coli can be done by rolling a prepared membrane filter onto the m-TEC agar and incubating for two hours at 35 °C. The the plate is transferred to a water bath at 44.5 °C for 22 to 24 hours. Then the filter is transferred aseptically to an absorbent pad saturated with urea broth. After 15 to 20 minutes at room temperature, the yellow or yellow-brown colonies are counted as presumptive E. coli True False
True
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT. Streptococci have been referred to as enterococci, fecal streptococci and group D streptococci. When membrane filtration started in 1986 they were investigated as a indicator organism for water quality standards. True False
True
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT. The membrane filter technique for fecal streptococci is useful for testing both fresh and marine waters. On the other hand, the MPN test uses a specified number of tubes (based on the expected population in the sample) containing a specific medium and sample water. After incubation, each tube is examined for growth of the target organism(s). The number of tubes showing growth are matched to a statistically determined table of numbers to yield the most probable number of organisms in the sample. True False
True
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT. When testing for fecal coliforms, a selective medium and an elevated incubation temperature are used to inhibit the growth of nonfecal coliforms. The formation of blue colonies is considered a positive result. Nonfecal colonies are gray to cream-colored. However, few nonfecal colonies are observed when rosolic acid salt reagent is added as an inhibitor. True False
True
USGS Fecal Indicator Bacteria 7.1 pg 19 or page 110 TCR Rule EPA "The TCR requires systems to monitor for total coliforms at a frequency proportional to the number of people served. If any sample tests positive for total coliforms, the system must perform the following additional tests: •Further test that culture for the presence of either fecal coliforms or Escherichia coli; •Take one set of 3-4 repeat samples at sites located within 5 or fewer sampling sites adjacent to the location of the routine positive sample within 24 hours; and •Take at least 5 routine samples the next month of operation True False
True
An ideal indicator organism should_________________________. Select one: a. be able to survive in all water types b. always be present in when when pathogens are present and have a greater survival time in water then a pathogen c. disapper rapidly after a pathogen disappears d. always be absent in bacteriologically safe water e. be easy to test for w/out harming the person f. all of the above Correct
all of the above
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT What are the three main groups of indicator organisms that indicate that water pollution from intestinal waste has occurred? Select one: a. The coliform group b. fecal coliforms a subset of total coliforms c. Fecal streptococci and enterococus d. all of the above Correct
all of the above
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT Which of the following criteria are necessary for an indicator organims to be considered reliable in predicting a health risk? Select one: a. the organism must be exculsively of fecal origin and present in fresh fecal waste and easily tested for b. the organism must be in in greater numbers and live longer than the pathogen c. the organism must be MORE resistant to environmental stresses than the evil pathogen and not proliferate to an unrealistic amount. d. all of the above Correct
all of the above
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT "Coliform bacteria belong to the family Enterobacteriaceae but are further defined by functional characteristics rather than systematic genus and species. Which of the following are considered a member of the total coliform group (aerobic or facultative anerobic, gram negative, rod shaped, non-sporeforming bacteria, which ferment lactose with gas within 48 hrs at 35 to 37 degree C)." Select one: a. E. coli Enterobacteriaceae are rod-shaped, non-spore-forming, and gram-negativebacteria. b. A. aerogenes c. fecal streptococci (enterococci) d. all of the above Correct
all of the above
The Use of Indicator Organisms to. Assess Public Water Safety. Technical Information Series—Booklet No. 13 --HACH HANDOUT In m-Endo broth what indicator is used to indicate the presence of aldehyde from the fermentation of lactose. This indictor turns red in the presence of the aldehyde? a. carbolfuschin b. fushcin sulfite c. rosalic acid d. formaldehyde
fushcin sulfite
