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Abstract Staphylococcus aureusis an opportunistic pathogen frequently detected in environmental waters and commonly causes skin infections to water users.S. aureusconcentrations in fresh, brackish, and marine waters are positively correlated with water turbidity. To reduce the risk ofS. aureusinfections from environmental waters,S. aureussurvival (stability and multiplication) in turbid waters needs to be investigated. The aim of this study was to measureS. aureusin turbid fresh and brackish water samples and compare the concentrations over time to determine which conditions are associated with enhancedS. aureussurvival. Eighteen samples were collected from fresh and brackish water sources from two different sites on the east side of Oʻahu, Hawaiʻi.S. aureuswas detected in microcosms for up to 71 days with standard microbial culturing techniques. On average, the greatest environmental concentrations ofS. aureuswere in high turbidity fresh waters followed by high turbidity brackish waters. Models demonstrate that salinity and turbidity significantly predict environmentalS. aureusconcentrations.S. aureuspersistence over the extent of the experiment was the greatest in high turbidity microcosms with T90's of 147.8 days in brackish waters and 80.8 days in freshwaters. This study indicates that saline, turbid waters, in the absence of sunlight, provides suitable conditions for enhanced persistence ofS. aureuscommunities that may increase the risk of exposure in environmental waters. Practitioner PointsStaphylococcus aureusconcentrations, survival, and persistence were assessed in environmental fresh and brackish waters.Experimental design preserved in situ conditions to measureS. aureussurvival.Higher initialS. aureusconcentrations were observed in fresh waters with elevated turbidity, while sustained persistence was greater in brackish waters.Water turbidity and salinity were both positively associated withS. aureusconcentrations and persistence.Climate change leads to more intense rainfall events which increase water turbidity and pathogen loading, heightening the exposure risk toS. aureus.
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Introducing the Self‐Cleaning FiLtrAtion for Water quaLity SenSors ( SC‐FLAWLeSS ) system
Abstract Sensor‐based, semicontinuous observations of water quality parameters have become critical to understanding how changes in land use, management, and rainfall‐runoff processes impact water quality at diurnal to multidecadal scales. While some commercially available water quality sensors function adequately under a range of turbidity conditions, other instruments, including those used to measure nutrient concentrations, cease to function in high turbidity waters (> 100 nephelometric turbidity units [NTU]) commonly found in large rivers, arid‐land rivers, and coastal areas. This is particularly true during storm events, when increases in turbidity are often concurrent with increases in nutrient transport. Here, we present the development and validation of a system that can affordably provide Self‐Cleaning FiLtrAtion for Water quaLity SenSors (SC‐FLAWLeSS), and enables long‐term, semicontinuous data collection in highly turbid waters. The SC‐FLAWLeSS system features a three‐step filtration process where: (1) a coarse screen at the inlet removes particles with diameter > 397 μm, (2) a settling tank precipitates and then removes particles with diameters between 10 and 397 μm, and (3) a self‐cleaning, low‐cost, hollow fiber membrane technology removes particles ≥ 0.2μm. We tested the SC‐FLAWLeSS system by measuring nitrate sensor data loss during controlled, serial sediment additions in the laboratory and validated it by monitoring soluble phosphate concentrations in the arid Rio Grande river (New Mexico, U.S.A.), at hourly sampling resolution. Our data demonstrate that the system can resolve turbidity‐related interference issues faced by in situ optical and wet chemistry sensors, even at turbidity levels > 10,000 NTU.
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- PAR ID:
- 10455195
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Limnology and Oceanography: Methods
- Volume:
- 18
- Issue:
- 9
- ISSN:
- 1541-5856
- Page Range / eLocation ID:
- p. 467-476
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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