Potable Water – Total Coliforms/Escherichia coli Detection
Laboratory Fee
Schedule
Procedure #: MZZ0441A
CPT: N/A
Potable Water – Total Coliforms/Escherichia coli Detection
| 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 |