1. Evaluation of Tracers of Fecal Pollution in Drinking Water Distribution Systems
Walter Q. Betancourt and Minkyu Park Water and Energy Sustainable Technology Center. The University of Arizona
RESEARCH PROGRESS REPORT
UA-01-F2018
STATUS: Continuing, No Additional Funds Requested
Relationship to Technology Roadmap: Municipal Water Use Practices and Wastewater Reuse
Rationale:
Approach:
The Total Coliform Rule, a National Primary Drinking Water Regulation (NPDWR), uses Escherichia coli (E. coli) as a fecal indicator and total coliform (TC) to determine the adequacy of water treatment and the integrity of the drinking water distribution system (DWDS)
Host-specific bacterial gene sequences (genetic markers) and chemical compounds (fecal sterols) associated with humans and animals can be measured by highly sensitive analytical methods that provide more accurate and rapid (same-day) results than the culture-based method for E. coli and total coliforms
Collect water samples from DWDS served by groundwater, 98% Central Arizona Project water, and water treated by advanced oxidation processes
Apply Colilert, qPCR and GC-MS/MS for quantitative analysis of E. coli -TC, genetic markers and fecal sterols, respectively
Human markers (qPCR): HF183, LACHNOS, C. coccoides, Blautia
Ruminant fecal markers (CF193, Rum2Bac, CowM2 and CowM3)
Avian fecal marker (GFD)
Fecal sterols (GC-MS/MS): coprostanol, epicoprostanol, 24-ethylcoprostanol, and sitostanol
Objectives:
Key Deliverables:
Compare analytical methods for microbial and chemical tracers of fecal pollution with the total coliform and E. coli assay
Conduct quantitative analysis of genetic markers and fecal sterols in water distribution systems
Develop a sensitive and reliable quantitative assay for rapid evaluation of drinking water safety in distribution systems
Provide a sensitive and rapid (same-day results) approach to ascertain for fecal contamination in drinking water distribution systems based on the analysis of genetic markers and fecal sterols
Demonstrate the robustness of the microbial and chemical tracer analysis over the culture-based assay for total coliforms and E. coli to ascertain for drinking water safety in the distribution system
Accomplishments:
Development of all standard curves and methods for precise quantification of genetic markers by quantitative PCR assays (qPCR) and fecal sterols by gas chromatography-mass spectrometry (GC-MS/MS)
Project Duration:
July 1, 2018 – June 30, 2019
Water & Environmental Technology Center