Potable Water – Total Coliforms/Escherichia coli Detection

Laboratory Fee Schedule
Procedure #: MZZ0441A
CPT: N/A

Synonym(s):	Total coliform, Drinking Water Test
Requisition Form	G-19
Test Description	Detects the presence of E. coli and total coliform bacteria in potable water
Pre-Approval Needed	N/A
Supplemental Information Required	N/A
Supplemental Form(s)	N/A
Performed on Specimens from (sources)	Food
Sample/Specimen Type for Testing	Water (potable; non-silo dairy) samples
Minimum Volume/Size Required	105 mL
Storage/Preservation Prior to Shipping	Place sample in water-tight, wide-mouthed container with a capacity of at least 120 mL (4 oz). Sodium thiosulfate (100mg/L) must be added to containers before sterilization (0.1 mL of 10% sodium thiosulfate solution, appropriate tablet, or powder). Potable water samples must be tested within 30 hours of collection. Non-silo dairy water samples must be tested within 6 hours of collection if not refrigerated (temperature control not required); or maintained at 0.0° to 4.5°C and shipment must include temperature control.
Transport Medium	N/A
Specimen Labeling	Sample Identification must match submission form.
Shipping and Specimen Handling Requirements	If shipped, samples must be shipped for overnight delivery. Potable water samples must be tested within 30 hours of collection. Non-silo dairy water samples that will not be tested within 6 hours of collection must be maintained between 0.0° to 4.5°C while in transit and include a temperature control.
Method	Colilert® test
Turn-around Time	1 Day
Interferences/Limitations	Can detect E. coli and/or total coliform bacteria at a sensitivity of 1 CFU/100 mL. In samples with excessive chlorine, a blue flash may be seen when adding Colilert® or Colilert®-18. If this occurs, sample will be considered invalid and testing will be discontinued.
Common Causes for Rejection	Insufficient specimen Improperly stored Failure to meet shipping guidelines
Additional Information	N/A