학술논문
Same-day EnterococcusqPCR results of recreational water quality at two Toronto beaches provide added public health protection and reduced beach days lost
Document Type
Article
Source
Canadian Journal of Public Health = Revue Canadienne de Sante Publique; August 2023, Vol. 114 Issue: 4 p676-687, 12p
Subject
Language
ISSN
00084263; 19207476
Abstract
Objectives: We evaluated the potential impacts from using a rapid same-day quantitative polymerase chain reaction (qPCR) monitoring method for beach posting outcomes at two Toronto beaches. Methods: In total, 228 water samples were collected at Marie Curtis Park East and Sunnyside Beaches over the 2021 summer season. Water samples were processed using the USEPA 1609.1 EnterococcusqPCR-based method. Escherichia coli(E. coli) culture data and daily beach posting decisions were obtained from Toronto Public Health. Results: No significant correlation was observed between previous-day and same-day (retrospective) E. colienumeration results at any Sunnyside Beach transect, and only relatively low (R= 0.41–0.56) or no significant correlation was observed at sampling transects for Marie Curtis Park East Beach. Comparing our same-day EnterococcusqPCR data to Toronto’s 2-day E. coligeometric mean beach posting decisions, we noted the need for additional postings for 1 (2%) and 3 (8%) missed health-risk days at Sunnyside and Marie Curtis Park East Beaches, respectively. The qPCR data also pointed to incorrect postings for 12 (31%) and 6 (16%) lost beach days at Sunnyside and Marie Curtis Park East Beaches, respectively. Conclusion: Application of a rapid EnterococcusqPCR method at two Toronto beaches revealed 5% of beach posting decisions were false negatives that missed health-risk days, while 23% of decisions were false positives resulting in lost beach days. Deployment of the rapid same-day qPCR method offers the potential to reduce both health risks and unnecessary beach postings.