Near real-time notification of water quality impairments in recreational freshwaters using rapid online detection of β-D-glucuronidase activity as a surrogate for Escherichia coli monitoring

摘要: Abstract Waterborne disease outbreaks associated with recreational waters continue to be reported around the world despite existing microbiological water quality monitoring frameworks. Most regulations resort use of culture-based enumeration faecal indicator bacteria such as Escherichia coli protect bathers from gastrointestinal illness risks. However, long sample-to-result time standard assays (minimum 18–24 h) and infrequent regulatory sampling (weekly or less) do not enable detection episodic impairments public health The objective this study was assess suitability an autonomous online technology measuring β-D-glucuronidase (GLUC) activity for near real-time in resulting beach management decisions. GLUC E. concentrations were monitored at three freshwater sites Quebec, Canada (sites Qc1-3) one site New Zealand (site NZ) between 2016 2018. We found site-dependent linear relationships using confusion matrices, we developed site-specific action values (BAVs) matching BAVs. Using BAV gold standard, rates false alarms (unnecessary advisories BAV) failures act (failure trigger activity) ranged 0 32% 3 10%, respectively, which is comparable other studies qPCR-defined a major benefit enzymatic reporting threshold exceedances, while temporal trends can assist understanding underlying dynamics pollution potential Our first describe applicability tool improved protection.