Rapid dead-end ultrafiltration concentration and biosensor detection of enterococci from beach waters of Southern California

Same-day microbial water quality assessments are not possible with standard methods, which increases the possibility of public exposure to fecal pathogens. This study examined the efficacy of high-volume hollow fibre ultrafiltration coupled to biosensor detection for enterococci in marine waters to allow same-day public notification of poor water quality. Fifty-six 100 l ultrafiltered samples and 100 ml grab samples were collected weekly from May to July 2007. Post-ultrafiltration processing included sonication and micron sieve passage to remove interfering particulates, followed by centrifugation for secondary concentration. Levels of enterococci in grab and ultrafiltration samples were determined by a standard method (EPA method 1600) for calculation of recovery efficiencies and concentration factors. Each final retentate was analysed with the RAPTOR evanescent wave biosensor. Enterococci levels increased over 26,000-fold in final retentates. Enterococci were detected when ambient concentrations exceeded the regulatory standard for a single sample (≥105 CFU/100 ml), and detection was highly correlated with breaches of the single-sample regulatory limit. The combined procedure required 2.5 h for detection compared with 24 h for EPA method 1600. This field study achieved rapid detection of enterococci by ultrafiltration, secondary concentration and biosensor analysis, and demonstrates its potential usefulness for water quality monitoring.

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Surface water quality monitoring, classification, biological assessment and standards

Water Science & Technology ◽

10.2166/wst.1994.0505 ◽

1994 ◽

Vol 30 (10) ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Peter J. Newman ◽

Stephen C. Nixon ◽

Yvonne J. Rees

Keyword(s):

Water Quality ◽

Surface Water ◽

Sediment Quality ◽

Surface Water Quality ◽

Water Quality Monitoring ◽

Biological Assessment ◽

Physical Measurements ◽

Potable Water Supply ◽

Water And Sediment Quality ◽

Quality Assessments

Poor surface water quality is still a significant problem in many parts of the world. It can often limit the use of this vital resource and in more extreme cases can harm human and other life. A basic need is to establish the nature, extent and magnitude of the problems. To gain a quantitative picture it is necessary to undertake detailed quality and status assessments. Such assessments establish the scope of environmental impacts and effects, and provide a quantitative baseline against which future quality can be compared and progress monitored. Quality assessments or status reviews would enable the key problems and issues to be defined, and their magnitude and importance quantified. Problems for priority action can then be identified. Once key problems have been identified there are mechanisms to enact improvements and changes. These include the setting of standards and targets for water and sediment quality, quite often for defined actual or potential uses of the waters, such as for example for potable water supply and for fisheries. Compliance with the standards and progression towards the targets has to be assessed generally through appropriate monitoring. Monitoring might include biological as well as chemical and physical measurements of quality, and these might also be expressed as some form of index of quality. Periodic assessments of general quality on a national or international basis are also used to monitor overall progress. Nationally this might entail the use of general classification schemes expressing quality as a combined index or score, or individually for different components of the aquatic system, e.g. chemical, biological, aesthetic, and sediment quality.

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Turbidity tubes for drinking water quality assessments

Journal of Water Sanitation and Hygiene for Development ◽

10.2166/washdev.2011.058 ◽

2011 ◽

Vol 1 (4) ◽

pp. 233-241 ◽

Cited By ~ 3

Author(s):

Caetano C. Dorea ◽

Murray R. Simpson

Keyword(s):

Water Quality ◽

Drinking Water ◽

Low Cost ◽

Water Quality Monitoring ◽

Field Method ◽

Drinking Water Quality ◽

Quality Monitoring ◽

Target Shape ◽

Resource Limited ◽

Quality Assessments

Turbidity tubes have been considered to be the field method of choice for drinking water quality monitoring in resource-limited contexts because of their relative simplicity and low cost in comparison with conventional (nephelometric) turbidimeters. These tubes utilise the principle of visual extinction of a submerged target for turbidity determination and were therefore thought to be subject to user subjectivity, possibly affecting results. This study evaluated their performance under both field and controlled-laboratory conditions. Results from turbidity tubes can differ substantially from those obtained with conventional turbidimeters; this is of particular importance in the reporting of low turbidity (<10 NTU) measurements. These differences could be due to a combination of factors, such as: user variability, differences in calibration scales, and turbidity tube target shape and background colour. In view of their limitations, the usefulness of turbidity tubes for drinking water quality assessments and recommendations on the reporting of their results are also discussed.

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The inland water macro-invertebrate occurrences in Flanders, Belgium

ZooKeys ◽

10.3897/zookeys.759.24810 ◽

2018 ◽

Vol 759 ◽

pp. 117-136 ◽

Cited By ~ 1

Author(s):

Rudy Vannevel ◽

Dimitri Brosens ◽

Ward De Cooman ◽

Wim Gabriels ◽

Frank Lavens ◽

...

Keyword(s):

Water Quality ◽

Sediment Quality ◽

Open Data ◽

Monitoring Network ◽

Water Quality Monitoring ◽

Biological Data ◽

Background Information ◽

Monitoring Networks ◽

Spatial Coverage ◽

Quality Assessments

The Flanders Environment Agency (VMM) has been performing biological water quality assessments on inland waters in Flanders (Belgium) since 1989 and sediment quality assessments since 2000. The water quality monitoring network is a combined physico-chemical and biological network, the biological component focusing on macro-invertebrates. The sediment monitoring programme produces biological data to assess the sediment quality. Both monitoring programmes aim to provide index values, applying a similar conceptual methodology based on the presence of macro-invertebrates. The biological data obtained from both monitoring networks are consolidated in the VMM macro-invertebrates database and include identifications at family and genus level of the freshwater phyla Coelenterata, Platyhelminthes, Annelida, Mollusca, and Arthropoda. This paper discusses the content of this database, and the dataset published thereof: 282,309 records of 210 observed taxa from 4,140 monitoring sites located on 657 different water bodies, collected during 22,663 events. This paper provides some background information on the methodology, temporal and spatial coverage, and taxonomy, and describes the content of the dataset. The data are distributed as open data under the Creative Commons CC-BY license.

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