The disparity between regulatory measurements of E. coli in public bathing waters and the public expectation of bathing water quality

Monitoring the quality of the bathing waters of Gipuzkoa (the Basque Country, Spain) makes it possible to assess the suitability of its 15 beaches for bathing throughout each season. In 1998, the parameters E. coli, somatic coliphages (SOMCPH) and F-specific RNA bacteriophages (FRNAPH) were incorporated into the bathing water quality monitoring system. This enabled the study of the link between bacterial and viral indicators as well as the analysis of the ratios between both types of indicators in waters with different levels of pollution. Although bacterial indicators (total coliforms (TC) and faecal coliforms (FC)) and enterococci showed a strong correlation between them, the correlations between the viral indicators and between the viral and bacterial indicators were weaker, though significant in all cases. The ratio between SOMCPH and E. coli indicates that at low levels of bacterial pollution (E coli <100 MPN/100 ml) SOMCPH outnumber E coli. In contrast, at higher levels of pollution (E coli >100 MPN/100 ml), SOMCPH numbers are lower than those of E-coli. The data reveal the presence of viral indicators in waters classified as suitable for bathing by the European Directive and alert us to their suitability.

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Development of a New Predictive index (Bathing Water Quality Index, BWQI) Based on Escherichia coli Physiological States for Bathing Waters Monitoring

Journal of Marine Science and Engineering ◽

10.3390/jmse9020120 ◽

2021 ◽

Vol 9 (2) ◽

pp. 120

Author(s):

Simone Bonamano ◽

Alice Madonia ◽

Gabriella Caruso ◽

Giuseppe Zappalà ◽

Marco Marcelli

Keyword(s):

Escherichia Coli ◽

Water Quality ◽

Water Quality Index ◽

Quality Index ◽

Fluorescent Antibody ◽

Predictive Tool ◽

E Coli ◽

Bathing Water ◽

Bathing Waters ◽

Bathing Water Quality

Bacterial pathogens in coastal aquatic ecosystems pose a potential public health hazard for bathing water use. The European Bathing Water Directive (2006/7/EC) currently relies on the culturability of fecal pollution bacterial indicators such as Escherichia coli, without considering dormant or quiescent (Viable But Not Culturable, VBNC) cells, whose possible resuscitation after bathers ingestion cannot be excluded. Standard methods are also time-consuming and therefore hardly meet early warning needs of marine monitoring. To solve this issue, a new index, the Bathing Water Quality Index (BWQI), has here been developed, allowing to identify the most favorable coastal zones for recreational use. The index was calculated by combining numerical simulations of living and dormant E. coli abundances and their residence times. To specifically set up the model with the different physiological states of the whole E. coli population, an ad hoc experiment based on the fluorescent antibody method was performed. The BWQI application to Santa Marinella bathing area highlights a potential risk for human health in the zone most frequented by bathers. This study provides a predictive tool to support preventive decisions of the competent authorities and to properly protect bathers’ health, stressing the need for improved methods for environmental monitoring.

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Modeling of <i>E. coli</i> distribution for hazard assessment of bathing waters affected by combined sewer overflows

Natural Hazards and Earth System Science ◽

10.5194/nhess-20-1219-2020 ◽

2020 ◽

Vol 20 (5) ◽

pp. 1219-1232 ◽

Cited By ~ 1

Author(s):

Luca Locatelli ◽

Beniamino Russo ◽

Alejandro Acero Oliete ◽

Juan Carlos Sánchez Catalán ◽

Eduardo Martínez-Gomariz ◽

...

Keyword(s):

Water Quality ◽

Hazard Assessment ◽

Health Hazard ◽

Water Bodies ◽

Combined Sewer Overflows ◽

Bathing Water ◽

Bathing Waters ◽

Combined Sewer ◽

Bathing Water Quality

Abstract. Combined sewer overflows (CSOs) affect bathing water quality of receiving water bodies by bacterial pollution. The aim of this study is to assess the health hazard of bathing waters affected by CSOs. This is useful for bathing water managers, for risk assessment purposes, and for further impact and economic assessments. Pollutant hazard was evaluated based on two novel indicators proposed in this study: the mean duration of insufficient bathing water quality (1) over a period of time (i.e., several years) and (2) after single CSO/rain events. In particular, a novel correlation between the duration of seawater pollution and the event rainfall volume was developed. Pollutant hazard was assessed through a coupled urban drainage and seawater quality model that was developed, calibrated and validated based on local observations. Furthermore, hazard assessment was based on a novel statistical analysis of continuous simulations over a 9-year period using the coupled model. Finally, a validation of the estimated hazard is also shown. The health hazard was evaluated for the case study of Badalona (Spain) even though the methodology presented can be considered generally applicable to other urban areas and related receiving bathing water bodies. The case study presented is part of the EU-funded H2020 project BINGO (Bringing INnovation to OnGOing water management – a better future under climate change).

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Stormwater overflow impacts on the sanitary quality of bathing waters

Water Science & Technology ◽

10.2166/wst.2007.742 ◽

2007 ◽

Vol 56 (11) ◽

pp. 43-50 ◽

Cited By ~ 5

Author(s):

E. Soyeux ◽

F. Blanchet ◽

B. Tisserand

Keyword(s):

Water Quality ◽

Urban Areas ◽

Active Management ◽

Bathing Water ◽

Bathing Waters ◽

Management Concept ◽

On Line ◽

Bathing Water Quality ◽

High Level ◽

Water Quality Deterioration

New European Directive 2006/7/EC concerning the management of bathing water quality introduces the concept of ‘active management of bathing water sanitary quality’ which could lead to a temporary bathing prohibition in case of short term pollution. For the last three bathing seasons, Veolia has carried out in experimental mode this ‘active management’ concept at more than one hundred bathing sites with various characteristics. Results confirm the high level of microbiological pollution observed in sewer overflows during rainy periods, which is the main cause of bathing water quality deterioration. An on-line treatment solution has been successfully tested. This solution may be used in dense urban areas.

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Assessment of bathing water quality with an E. coli immunosensor

International Journal of Environmental & Analytical Chemistry ◽

10.1080/03067319.2020.1786549 ◽

2020 ◽

pp. 1-12

Author(s):

Eerik Jõgi ◽

Ingrid Väling ◽

Toonika Rinken

Keyword(s):

Water Quality ◽

E Coli ◽

Bathing Water ◽

Bathing Water Quality

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Evaluating health hazard of bathing waters affected by combined sewer overflows

10.5194/nhess-2019-292 ◽

2019 ◽

Cited By ~ 2

Author(s):

Luca Locatelli ◽

Beniamino Russo ◽

Montse Martinez

Keyword(s):

Water Quality ◽

Sea Water ◽

Health Hazard ◽

Water Bodies ◽

Combined Sewer Overflows ◽

Bathing Water ◽

Bathing Waters ◽

Combined Sewer ◽

Sewer Overflows ◽

Bathing Water Quality

Abstract. Combined Sewer Overflows (CSO) affect bathing water quality of receiving water bodies by bacterial contamination. The aim of this is study is to assess the health hazard of bathing waters affected by CSOs. This is useful for bathing water managers, for risk assessment purposes and for further impact and economical assessments. Contaminant hazard was evaluated based on two novel indicators proposed in this study: the mean duration of insufficient bathing water quality (1) over a period of time (i.e. several years) and (2) after single CSO/rain events. Particularly, a novel correlation between the duration of sea water contamination and the event rainfall volume was developed. Contaminant hazard was assessed through a state-of-the-art coupled urban drainage and sea water quality model that was developed, calibrated and validated based on local observations. Furthermore, hazard assessment was based on a novel statistical analysis of continuous simulations over a 9 year period using the coupled model. Finally, a validation of the estimated hazard is also shown. The health hazard was evaluated for the case study of Badalona (Spain) even though the methodology presented can be considered generally applicable to other urban areas and related receiving bathing water bodies.

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The association of weather and bathing water quality on the incidence of gastrointestinal illness in the west of Scotland

Epidemiology and Infection ◽

10.1017/s0950268813002148 ◽

2013 ◽

Vol 142 (6) ◽

pp. 1289-1299 ◽

Cited By ~ 8

Author(s):

J. I. EZE ◽

E. M. SCOTT ◽

K. G. POLLOCK ◽

R. STIDSON ◽

C. A. MILLER ◽

...

Keyword(s):

Water Quality ◽

Relative Humidity ◽

Future Climate Change ◽

Indicator Organisms ◽

Gastrointestinal Infections ◽

Bathing Water ◽

Bathing Waters ◽

Using Data ◽

Bathing Water Quality

SUMMARYThe associations with weather and bathing water quality on infectious intestinal disease (IID) were investigated using data from two Scottish NHS Board areas. Monthly counts of viral and non-viral gastrointestinal infections were modelled as a smooth function of temperature, relative humidity and average monthly counts of faecal indicator organisms, respectively, adjusting for season and long-term trend effects. Strong seasonal patterns were observed for each group of pathogens. Peak viral gastrointestinal infection was in May while that of non-viral gastrointestinal infections was in July. A statistically significant negative association existed between weather (temperature and humidity) and viral infection. Average levels of non-viral gastrointestinal infections increased as temperature and relative humidity increased. Increasing levels of faecal indicator organisms in bathing waters were also associated with an increase in the average number of viral and non-viral gastrointestinal infections at the ecological level. Future climate change and prolonged precipitation events may result in increasing levels of faecal indicator organisms in bathing waters leading to likely increases in IIDs.

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Disease outbreaks associated with untreated recreational water use

Epidemiology and Infection ◽

10.1017/s0950268810002347 ◽

2010 ◽

Vol 139 (7) ◽

pp. 1114-1125 ◽

Cited By ~ 21

Author(s):

F. M. SCHETS ◽

A. M. DE RODA HUSMAN ◽

A. H. HAVELAAR

Keyword(s):

Public Health ◽

Water Quality ◽

Water Use ◽

Disease Outbreaks ◽

Recreational Water ◽

The Public ◽

Bathing Water ◽

Water Legislation ◽

Skin Conditions ◽

Bathing Water Quality

SUMMARYAnnual overviews of waterborne disease outbreaks associated with untreated recreational water use provided by authorities responsible for bathing-water quality and public health in The Netherlands revealed 742 outbreaks during 1991–2007 mainly comprising of skin conditions (48%) and gastroenteritis (31%) and involving at least 5623 patients. The number of outbreaks per bathing season correlated with the number of days with temperatures over 25°C (r=0·8–0·9), but was not reduced through compliance with European bathing-water legislation (r=0·1), suggesting that monitoring of faecal indicator parameters and striving for compliance with water-quality standards may not sufficiently protect bathers. Bathing sites were prone to incidental faecal contamination events or environmental conditions that favoured the growth of naturally occurring pathogens. Identification of all possible contamination sources, awareness of changes that might negatively affect water quality, and provision of adequate information to the public are important preventive measures to protect public health.

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