Total Coliform Rule
False
The EPA set the maximum contaminant health goal (MCLG) for total coliforms at 50CFU/100 ml of sample. True False
True
The TCR requires all public water systems (PWSs) to monitor for the presence of total coliforms in the distribution system True False
True
m-Endo broth contains peptone which is a source of carbon, nitrogen, vitamins, and minerals. Yeast extract supplies B-complex vitamins for bacterial growth. In general, peptone and yeast always perform these functions regardless of what broth they are in.. True False
False
m-Enterococcus agar utlizes lactose as its ferementing agent? True False
True
For m-Endo broth to work total coliforms must ferment lactose to gas. However, the key compoent is that they produce aldehyde during fermentation. Aldehyde reacts with sodium sulfite and fuschin to form red colonies. Additionally, aldehyde is responsible for the metallic sheen around colonies. Talk about maximizing a by-product of fermentation! True False
True
If a sample tests positive for coliforms, the system must collect a set of repeat samples within 24 hours. True False
(1989) "The Total Coliform Rule (TCR), which was published in 1989, set both health goals (MCLGs) and legal limits (MCLs) for the presence of total coliforms in drinking water
What year was the total coliform rule published? a. 1970 b. 1974 c. 1989 d. 1996
All of the above
Which of the following are indicators for bacterial growth (E. coli) using m-TEC agar? a. Bromcresol purple b. Bromphenol red c. All of the above
Sodium azide
Which of the following is designed to suppress gram negative bacteria using m-Enterococcus? a. Agar b. Sodium azide c. Tripheny tetrazolium chloride (TTC) d. All of the above
all of the above
Which of the following is/are inhibitors of gram positive bacteria? a. Bile Salt #3 (m-FC) b. sodium desoxycholate and sodium lauryl sulfate (m-Endo) c. sodium desoxycholate and sodium lauryl sulfate (m-TEC) d. all of the above
0.01 ml
"A sample of raw influent is collected from CWS (sample A). After shaking the bottle 10 ml of sample is diluted with 90 ml of sterilized DI water (sample B). After shaking this bottle you take one ml of sample and dilute with another 9 ml of sterilized DI water (sample C). What is the final concentration in the last bottle (sample C)? " a. .1 ml b. 0.01 ml c. .001 ml d. .0001 ml
True
"For the TCR an acute MCL violation, necessitates rapid state and public notification because it represents a direct health risk." True False
True
"The number of coliform samples a system must take depends on the number of customers that it serves. Systems which serve fewer than 1000 people may test one sample a month, while systems with 49,990 customers test 50 samples per month and those with 2.5 million customers test at least 420 samples per month, if you are greater than 4 million people you max out at 480 samples. " True False
lactose
"Total coliforms belong within the family Enterobacteriaceae and have been defined in the 20th edition of Standard Methods for the Examination of Water and Wastewater (APHA et al., 1998) as follows: (1) all facultative anaerobic, Gram-negative, non-spore-forming, rod-shaped bacteria that ferment lactose with gas and acid formation within 48 hours at 35°C; (2) many facultative anaerobic, Gram-negative, non-spore-forming, rod-shaped bacteria that develop red colonies with a metallic (golden) sheen within 24 hours at 35°C on an Endo-type medium containing __________________; or (3) all bacteria possessing the enzyme β-galactosidase, which cleaves a chromogenic substrate (e.g., ortho-nitrophenyl-β-D-galactopyranoside), resulting in release of a chromogen (ortho-nitrophenol). " a. lactose b. fructose c. sucrose d. maltose
True
"When a routine or repeat sample tests positive for total coliforms, it must also be analyzed for fecal coliforms and Escherichia coli (E. coli), which are a type of coliform bacteria that are directly associated with fresh feces. A positive result to this last test signifies an acute MCL violation." True False
True
"When the news media announce a "boil water emergency," reporters often speak of a "total coliform violation." Coliforms are a group of bacteria, most of which are harmless. At first glance, it might seem strange that a harmless group of bacteria such as coliforms could cause such commotion. But like police tape and chalk outlines, coliform bacteria are often found at the scene of a crime even though they are not themselves criminals. " True False
0.000001 ml
A sample of raw influent is collected from CWS (sample A). After shaking the bottle 1 ml of sample is diluted with 999 ml of sterilized DI water (sample B). After shaking this bottle you take one ml of sample and dilute with another 999 ml of sterilized DI water (sample C). What is the final concentration in the last bottle (sample C)? a. 0.1 ml b. 0.001 ml c. 0.000001 ml d. 0.0001 ml
True
For fecal coliforms a 100 ml volume of a water sample is drawn through a membrane filter 45 micron pore size) with the use of a vacuum pump. The filter is placed on a petri dish containing M-FC broth and incubated in a water bath for 24 hours at 44.5o C. This elevated temperature heat shocks non-fecal bacteria and suppresses their growth. ---As the fecal coliform colonies grow they produce an acid (through fermenting lactose) that reacts with the aniline dye in the agar thus giving the colonies their blue color.-- True False
membrane "The membrane filter (MF) technique is highly reproductible, can be used to test relatively large volumes of sample, and yields numerical results more rapidly than the multiple-tube procedure "Use m-Endo Broth is used for enumerating coliforms in water by the membrane filtration method"
The m in m-endo, m-FC, m-Enterococcus, and m-Tec stands for? a. membrane b. modified c. microbial d. matching
pathogenic
The presence of any coliforms in drinking water suggests that there may be disease-causing agents in the water. Which of the following is considered disease causing? a. pathogenic b. disinfectants c. sterilization
~71CFU/100 ml (non-deal) Rule #4 If ALL counts are positive and BELOW the acceptable range, sum the colonies and divide by the sum of their sample volumes (include 0 counts if bracketed). 13+9+7/41ml X 100 = ~71CFU/100 ml (nonideal)
You remove your filters and count the colony forming units in class. Based on this data set the correct total coliform count would be: RULE ________: 1b). ml of sample RAW count 1 7 10 9 30 13 What is the final CFU/100 ml value you would report? a. ~ 90 CFU/100 ml (non ideal) b. 59CFU/100 ml c. ~71CFU/100 ml (non-deal) d. 80CFU/100 ml
>8,000CFU/100ml (non ideal) Rule # 8 If counts are TNTC on all plates, use the upper ideal range limit and the smallest sample volume. 80/1 X 100 ml = >8,000CFU/100ml The correct answer is: >8,000CFU/100ml (non ideal)
You remove your filters and count the colony forming units in class. Based on this data set the correct total coliform count would be: RULE ________: 1b). ml of sample RAW count 1 TNTC 10 TNTC 30 TNTC What is the final CFU/100 ml value you would report? a. 80CFU/100ml (non ideal) b. 800CFU/100ml (non ideal) c. >8,000CFU/100ml (non ideal) d. 50cfu/100ml
~ <3.0CFU/100ml (Non Ideal) Rule #1 If NO plates have colonies, use the largest sample volume and <1 as the count. 1/30 ml X 100 = <3.0CFU/100 ml (non Ideal)
You remove your filters and count the colony forming units in class. Your group did not have any total coliforms, based on this data set the coliform count: RULE ________: 1b). ml of sample RAW count 1 0 10 0 30 0 What is the final CFU/100 ml value you would report? a. ~ <3.0CFU/100ml (Non Ideal) b. 0 c. <10 CFU/100 ml (non-ideal) d. <80CFU/100 ml
~188 CFU/100 ml (Non ideal) Rule #3 If MORE than 1 plate is in the acceptable range, add the colonies w/in the range and divide them by the sum of their sample volumes . 26+49/40 X 100 = ~188 CFU/100 ml (non-ideal)
You remove your filters and count the colony forming units in class. Your group did not have any total coliforms, based on this data set the coliform count: RULE ________: 1b). ml of sample RAW count 1 0 10 26 30 49 What is the final CFU/100 ml value you would report? a. 49CFU/100 ml (Ideal) b. ~188 CFU/100 ml (Non ideal) c. 126 CFU/100ml d. 49CFU/100 ml
750CFU/100 ml (Ideal) Rule 2 If ONE plate has a count in the ideal range, use only that count and sample volume. 75/10 X 100 = 750 CFU/100 ml Ideal
You remove your filters and count the colony forming units in class. your group has obtained the following results for Total Coliform count: RULE ________: 1b). ml of sample RAW count 1 8 10 75 30 TNTC What is the final CFU/100 ml value you would report a. 83CFU/100 ml (Non-Ideal) b. 750CFU/100 ml (Ideal) c. 75CFU/100 ml (Non-Ideal) d. 26 CFU/100 ml