A human fecal contamination index for ranking impaired recreational watersusing the HF183 quantitative real-time PCR method
Cao, Y., Mano Sivaganesan, C. Kelty, D. Wang, A. Boehm, J. Griffith, S. Weisberg, AND O. Shanks. A human fecal contamination index for ranking impaired recreational watersusing the HF183 quantitative real-time PCR method. Presented at Water Microbiology Conference, UNC Water Institute, Chapel Hill, NC, May 17 - 19, 2016.
To inform the public.
Human fecal pollution of surface water remains a public health concern worldwide. As a result, there is a growing interest in the application of human-associated fecal source identification quantitative real-time PCR (qPCR) technologies for recreational water quality risk management. The transition from a research subject to a management tool requires the integration of standardized water sampling, laboratory, and data analysis procedures. In this study, a standardized HF183/BacR287 qPCR method was combined with a water sampling strategy and Bayesian data algorithm to establish a human fecal contamination index that can be used to rank impaired recreational water sites polluted with human waste. Stability and bias of index predictions were investigated under various parameters including siteswith different pollution levels, sampling period time range (1-15 weeks), and number of qPCR replicates per sample (2-14 replicates). Sensitivity analyses were conducted with simulated data sets (100 iterations) seeded with HF183/BacR287 qPCR laboratory measurements from water samples collected from three Southern California sites (588 qPCR measurements). Findings suggest that site ranking is feasible and that all parameters tested influence stability and bias in human fecal contamination indexscoring. Trends identified by sensitivity analyses will provide managers with the information needed to design and conduct field studies to rank impaired recreational water sites based on levels of human pollution.