title: The Microbiota of Recreational Freshwaters and the Implications for Environmental and Public Health.
abstract: The microbial communities in recreational freshwaters play important roles in both environmental and public health perspectives. In this study, the bacterial community structure and its associations with freshwater environments were investigated by analyzing the summertime microbiomes of three beach waters in Ohio (East Fork, Delaware, and Madison lakes) together with environmental and microbial water quality parameters. From the swimming season of 2009, 21 water samples were collected from the three freshwater beaches. From the samples, 110,000 quality-checked bacterial 16S rRNA gene sequences were obtained and analyzed, resulting in an observation of 4500 bacterial operational taxonomic units (OTUs). The most abundant bacteria wereMycobacteriumandArthrobacterof theActinobacteria(33.2%),ExiguobacteriumandPaenisporosarcinaof theFirmicutes(23.4%),PlanktothrixandSynechococcusof theCyanobacteria(20.8%), andMethylocystisandPolynucleobacterof theProteobacteria(16.3%). Considerable spatial and temporal variations were observed in the bacterial community ofActinobacteria, Cyanobacteria, andFirmicutes, where the bacterial community structure was greatly influenced by hydrological and weather conditions. The most influential factors were (1) water inflow forBacteroidiaandClostridia, (2) turbidity forGammaproteobacteria, (3) precipitation forBacilli, and (4) temperature and pH forCyanobacteria. One noticeable microbial interaction in the bacterial community was a significant negative relationship betweenCyanobacteriaandBacilli(P< 0.05). Concerning beach water quality, the level of the genetic markers for cyanobacterial toxin (mcyA) was linked to the abundance ofCyanobacteria. In addition, unique distributions of the generaEnterococcus, Staphylococcus, Streptococcus, Bacteroides, Clostridium, Finegoldia, Burkholderia, andKlebsiella, together with a high density of fecal indicatorEscherichia coli, were markedly observed in the sample from Madison Lake on July 13, suggesting a distinctly different source of bacterial loading into the lake, possibly fecal contamination. In conclusion, deep sequencing-based microbial community analysis can provide detailed profiles of bacterial communities and information on potential public health risks at freshwater beaches.
authors.affiliation: Division of Environmental Health Sciences, College of Public Health, The Ohio State University Columbus, OH, USA.
authors.forename: Chang Soo
authors.initials: CS
authors.lastname: Lee
authors.affiliation: Department of Animal Sciences, The Ohio State University Columbus, OH, USA.
authors.forename: Minseok
authors.initials: M
authors.lastname: Kim
authors.affiliation: Division of Environmental Health Sciences, College of Public Health, The Ohio State University Columbus, OH, USA.
authors.forename: Cheonghoon
authors.initials: C
authors.lastname: Lee
authors.affiliation: Department of Animal Sciences, The Ohio State University Columbus, OH, USA.
authors.forename: Zhongtang
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Division of Environmental Health Sciences, College of Public Health, The Ohio State UniversityColumbus, OH, USA; Department of Food Science and Technology, The Ohio State UniversityColumbus, OH, USA.
authors.forename: Jiyoung
authors.initials: J
authors.lastname: Lee
keywords: bacterial community; environmental factor; public health; pyrosequencing; quantitative PCR; recreational freshwater