| 1. |
- Boakye-Ansah, A. S., et al.
(författare)
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Inequalities in microbial contamination of drinking water supplies in urban areas : The case of Lilongwe, Malawi
- 2016
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1477-8920 .- 1996-7829. ; 14:5, s. 851-863
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Tidskriftsartikel (refereegranskat)abstract
- Over past decades strategies for improving access to drinking water in cities of the Global South have mainly focused on increasing coverage, while water quality has often been overlooked. This paper focuses on drinking water quality in the centralized water supply network of Lilongwe, the capital of Malawi. It shows how microbial contamination of drinking water is unequally distributed to consumers in low-income (unplanned areas) and higher-income neighbourhoods (planned areas). Microbial contamination and residual disinfectant concentration were measured in 170 water samples collected from in-house taps in high-income areas and from kiosks and water storage facilities in low-income areas between November 2014 and January 2015. Faecal contamination (Escherichia coli) was detected in 10% of the 40 samples collected from planned areas, in 59% of the 64 samples collected from kiosks in the unplanned areas and in 75% of the 32 samples of water stored at household level. Differences in water quality in planned and unplanned areas were found to be statistically significant at p < 0.05. Finally, the paper shows how the inequalities in microbial contamination of drinking water are produced by decisions both on the development of the water supply infrastructure and on how this is operated and maintained.
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| 2. |
- Börjesson, Stefan, 1979-, et al.
(författare)
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Genes encoding tetracycline resistance in a full-scale municipal wastewater treatment plant investigated during one year
- 2010
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1477-8920 .- 1996-7829. ; 8:2, s. 247-256
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Tidskriftsartikel (refereegranskat)abstract
- Tetracycline-resistant bacteria and genes encoding tetracycline resistance are common in anthropogenic environments. We studied how wastewater treatment affects the prevalence and concentration of two genes, tetA and tetB, that encode resistance to tetracycline. Using real-time polymerase chain reaction (PCR) we analysed wastewater samples collected monthly for one year at eight key-sites in a full-scale municipal wastewater treatment plant (WWTP). We detected tetA and tetB at each sampling site and the concentration of both genes, expressed per wastewater volume or per total-DNA, decreased over the treatment process. The reduction of tetA and tetB was partly the result of the sedimentation process. The ratio of tetA and tetB, respectively, to total DNA was lower in or after the biological processes. Taken together our data show that tetracycline resistance genes occur throughout the WWTP, and that the concentrations are reduced under conventional operational strategies.
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| 3. |
- Moreira, Nuno, et al.
(författare)
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Safe drinking water and waterborne outbreaks
- 2017
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1996-7829 .- 1477-8920. ; 15:1, s. 83-96
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Forskningsöversikt (refereegranskat)abstract
- The present work compiles a review on drinking waterborne outbreaks, with the perspective of production and distribution of microbiologically safe water, during 2000–2014. The outbreaks are categorised in raw water contamination, treatment deficiencies and distribution network failure. The main causes for contamination were: for groundwater, intrusion of animal faeces or wastewater due to heavy rain; in surface water, discharge of wastewater into the water source and increased turbidity and colour; at treatment plants, malfunctioning of the disinfection equipment; and for distribution systems, cross-connections, pipe breaks and wastewater intrusion into the network. Pathogens causing the largest number of affected consumers were Cryptosporidium, norovirus, Giardia, Campylobacter, and rotavirus. The largest number of different pathogens was found for the treatment works and the distribution network. The largest number of affected consumers with gastrointestinal illness was for contamination events from a surface water source, while the largest number of individual events occurred for the distribution network.
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| 4. |
- Navarro, PC, et al.
(författare)
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Antibiotic resistance in environmental Escherichia coli - a simple screening method for simultaneous typing and resistance determination
- 2014
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Ingår i: Journal of water and health. - : IWA Publishing. - 1477-8920 .- 1996-7829. ; 12:4, s. 692-701
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Tidskriftsartikel (refereegranskat)abstract
- We describe a simple and standardised screening system (AREB) for surveillance of antibiotic resistant bacteria in the environment. The system consists of 96 well microplates containing eight sets of breakpoint amounts of 10 different antibiotics. The incubated microplates are read by a desktop scanner and the plate images are analysed by special software that automatically presents the resistance data. The AREB method is combined with a rapid typing method, the PhenePlate system, which yields information on the diversity of the bacteria in the studied samples, and on the possible prevalence of resistant clones. In order to demonstrate the usage of AREB, a comparative study on the resistance situation among 970 Escherichia coli isolates from sewage and recipient water in Sweden, Norway and Chile, was performed. Resistance rates to all antibiotics were markedly higher in hospital sewage than in other samples. Our data indicate that the AREB system is useful for comparing resistance rates among E. coli and other environmental indicator bacteria in different countries/regions. Simple handling and automatic data evaluation, combined with low cost, facilitate large studies involving several thousands of isolates.
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| 5. |
- Ngubane, Zesizwe, et al.
(författare)
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Water quality modelling and quantitative microbial risk assessment for uMsunduzi River in South Africa
- 2022
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1996-7829 .- 1477-8920. ; 20:4, s. 641-656
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Tidskriftsartikel (refereegranskat)abstract
- South African rivers generally receive waste from inadequate wastewater infrastructure, mines, and farming activities, among others. The uMsunduzi River in KwaZulu-Natal, South Africa, is among these recipients with recorded poor to very poor water quality. To identify parts of the uMsunduzi River that are polluted by Cryptosporidium and Escherichia coli (E. coli), this study mapped out pollutants emanating from point and non-point sources using the Soil and Water Assessment Tool (SWAT). Streamflow calibration in the upper and lower reaches of the catchment showed good performance with R-2 of 0.64 and 0.58, respectively. SWAT water quality output data were combined with a Quantitative Microbial Risk Assessment (QMRA) to understand the microbial health implications for people using river water for drinking, recreational swimming, and non-competitive canoeing. QMRA results for Cryptosporidium and pathogenic E. coli showed that the probability of infection for most users exceeds the acceptable level for drinking and recreation as outlined in the South African water quality guidelines, and by the World Health Organisation (WHO). The results of this study can be used as a baseline to assess the economic and health implications of different management plans, resulting in better-informed, cost-effective, and impactful decision-making.
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| 6. |
- Nilsson, Per, et al.
(författare)
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SCADA data and the quantification of hazardous events for QMRA
- 2007
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1477-8920 .- 1996-7829. ; 5, s. 99-105
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to assess the use of on-line monitoring to support the QMRA at water treatment plants studied in the EU MicroRisk project. SCADA data were obtained from diary records, grab three Catchment-to-Tap Systems (CTS) along with system descriptions, sample data and deviation reports. Particular attention was paid to estimating hazardous event frequency, duration and magnitude. Using Shewart and CUSUM we identified 'change-points' corresponding to events of between 10 min and > 1 month duration in timeseries data. Our analysis confirmed it is possible to quantify hazardous event durations from turbidity, chlorine residual and pH records and distinguish them from non-hazardous variability in the timeseries dataset. The durations of most 'events' were short-term (0.5-2.3 h). These data were combined with QMRA to estimate pathogen infection risk arising from such events as chlorination failure. its interpretation was While analysis of SCADA data alone could identify events provisionally, severely constrained in the absence of diary records and other system information. SCADA data analysis should only complement traditional water sampling, rather than replace it. More work on on-line data management, quality control and interpretation is needed before it can be used for event characterization routinely for event characterrisation.
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| 7. |
- Ottoson et. al., Jakob
(författare)
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Tracking the origin of faecal pollution in surface water. An ongoing project within the European Union research programme
- 2004
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Ingår i: Journal of Water and Health. - 1477-8920 .- 1996-7829. ; 2:4, s. 249-260
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Tidskriftsartikel (refereegranskat)abstract
- The objectives of this study are to generate knowledge about methods to track the sources of faecal pollution in surface waters, with the aim of having one or a few easy procedures applicable to different geographic areas in Europe. For this, a first field study using already proposed methods (genotypes of F-specific RNA bacteriophages, bacteriophages infecting Bacteroides fragilis, phenotypes of faecal coliforms and enterococci, and sterols) has been done in five areas representing a wide array of conditions in Europe. The present faecal indicators (faecal coliforms, enterococci, sulfite reducing clostridia and somatic coliphages) have also been included in this first field study. At the same time some emerging methods have been settled or adapted to water samples and assayed in a limited number of samples. The results of this first field study indicate that no single parameter alone is able to discriminate the sources, human or non-human, of faecal pollution, but that a 'basket' of 4 or 5 parameters, which includes one of the present faecal indicators, will do so. In addition, numerical analysis of the data shows that this 'basket' will allow the successful building of predictive models. Both the statistical analyses and the studied predictive models indicate that genotype II of F-specific RNA bacteriophages, the coprostanol and the ratio coprostanol: coprostanol+epicoprostanol are, out of the studied parameters, those with a greater discriminating power. Either because unsuccessful adaptation of the methods to water samples or because the preliminary assays in water samples indicated low discriminating capability, only three (sorbitol-fermenting bifidobacteria, some species of bifidobacteria detected by PCR with specific primers and phages infecting Bacteroides tethaiotaomicron) of the newly assayed methods have been considered for a second field study, which is currently underway. Expectations are that these new tools will minimize the number of parameters in the 'basket', or at least minimize the difficulty in assaying them
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| 8. |
- Perez Mercado, Luis Fernando, et al.
(författare)
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Pathogens in crop production systems irrigated with low-quality water in Bolivia
- 2018
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1477-8920 .- 1996-7829. ; 16, s. 980-990
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Tidskriftsartikel (refereegranskat)abstract
- In dry areas, the need for irrigation to ensure agricultural production determines the use of all available water sources. However, the water sources used for irrigation are often contaminated by untreated or minimally treated wastewater. Microbial risks from reusing wastewater for vegetable irrigation can be addressed by installing environmental barriers that pathogens must cross to reach humans in the reuse system. Knowledge of pathogen flows inside the system and pathogen removal potential is the first step towards devising a risk management strategy. This study assessed microbe prevalence in farming systems in the Bolivian highlands that use wastewater-polluted sources for irrigation of lettuce. Samples of soil, lettuce and different water sources used in the farming systems were taken during one crop season and concentrations of coliphages, Escherichia coli and helminth eggs were measured. The results showed high spread of these microorganisms throughout the whole system. There was a significant correlation between microbial quality of water and of the harvested produce for several microorganisms. The microbial prevalence in protected shallow wells was found to be significantly lower than in other water sources. These findings can help formulate feasible risk management strategies in contexts where conventional technologies for microbial removal are not possible.
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| 9. |
- Ridderstedt, Frida, et al.
(författare)
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Sick leave due to diarrhea caused by contamination of drinking water supply with Cryptosporidium hominis in Sweden : a retrospective study
- 2018
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1477-8920 .- 1996-7829. ; 16:5, s. 704-710
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Tidskriftsartikel (refereegranskat)abstract
- We investigated sick leave from work, studies, preschool, and kindergarten occurring between 1 November 2010 and 31 January 2011 and associated with a waterborne outbreak of diarrhea caused by Cryptosporidium hominis in late November 2010 in Ostersund, Sweden with 45.2% of 60,000 residents being symptomatic. A questionnaire defining acute watery diarrhoea and/or >= 3 diarrhea episodes/day as cryptosporidiosis was sent to 1,508 residents in late January 2011 (response rate 69.2%). Among adults aged 18-60 years, 24.0% took sick leave for a mean of 4.6 (SD +/- 4.0) days due to cryptosporidiosis, and an additional 10.6% were absent from work a mean of 4.0 (+/- 2.2) days to care for symptomatic children. Among children (aged <= 17 years), 35.0% stayed home sick from kindergarten/preschool or school/university for a mean of 5.2 (+/- 3.8) days resulting in 5.1 (+/- 4.4) days of absence from work per sick child shared between parents/guardians. The estimated total number of sick leave days was 50,000 for adults and 20,700 for children, with an estimated direct cost of (sic) 7 million for employers. The potential impact on society of sick leave caused by waterborne diseases must be considered in decisions regarding the quality of drinking water.
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| 10. |
- Schönning, Caroline, et al.
(författare)
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Microbial risk assessment of local handling and reuse of human faeces
- 2007
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Ingår i: Journal of Water and Health. - : I W A Publishing. - 1477-8920 .- 1996-7829. ; 5:1, s. 117-128
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Tidskriftsartikel (refereegranskat)abstract
- Dry urine-diverting toilets may be used in order to collect excreta for the utilisation of nutrients. A quantitative microbial risk assessment was conducted in order to evaluate the risks of transmission of infectious disease related to the local use of faeces as a fertiliser. The human exposures evaluated included accidental ingestion of small amounts of faeces, or a mixture of faeces and soil, while emptying the storage container and applying the material in the garden, during recreational stays to the garden, and during gardening. A range of pathogens representing various groups of microorganisms was considered. Results showed that 12-months' storage before use was sufficient for the inactivation of most pathogens to acceptable levels. When working or spending time in the garden the annual risk of infection by Ascaris was still slightly above 10-4 in these scenarios, although the incidence rate for Ascaris is very low in the population in question. Measures to further reduce the hygienic risks include longer storage, or treatment, of the faeces. The results can easily be extended to other regions with different incidence rates.
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| 11. |
- Senecal-Smith, Jenna, et al.
(författare)
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Fate of Ascaris at various pH, temperature and moisture levels
- 2020
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1477-8920 .- 1996-7829. ; 18, s. 375-382
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Tidskriftsartikel (refereegranskat)abstract
- Soil-transmitted helminths (STH) are intestinal worms that infect 24% of the world's population. Stopping the spread of STH is difficult, as the eggs are resilient (can withstand high pH) and persistent (can remain viable in soils for several years). To ensure that new sanitation systems can inactivate STH, a better understanding of their resilience is required. This study assessed the inactivation ofAscariseggs under various conditions, in terms of moisture content (MC) (90%), temperature (20-50 degrees C) and pH (7-12.5). The results highlight that the exposure ofAscariseggs to elevated pH (10.5-12.5) at temperatures <= 27.5 degrees C for >70 days had no effect on egg viability. Compounding effects of alkaline pH (>= 10.5) or decreasing MC (<20%) was observed at 35 degrees C, with pH having more of an effect than decreasing MC. To accelerate the inactivation of STH, an increase in the treatment temperature is more effective than pH increase. Alkaline pH alone did not inactivate the eggs but can enhance the effect of ammonia, which is likely to be present in organic wastes.
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| 12. |
- Sokolova, Ekaterina, 1986, et al.
(författare)
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Estimation of pathogen concentrations in a drinking water source using hydrodynamic modelling and microbial source tracking
- 2012
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1477-8920 .- 1996-7829. ; 10:3, s. 358-370
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Tidskriftsartikel (refereegranskat)abstract
- The faecal contamination of drinking water sources can lead to waterborne disease outbreaks. To estimate a potential risk for waterborne infections caused by faecal contamination of drinking water sources, knowledge of the pathogen concentrations in raw water is required. We suggest a novel approach to estimate pathogen concentrations in a drinking water source by using microbial source tracking data and fate and transport modelling. First, the pathogen (norovirus, Cryptosporidium, Escherichia coli O157/H7) concentrations in faecal contamination sources around the drinking water source Lake Rådasjön in Sweden were estimated for endemic and epidemic conditions using measured concentrations of faecal indicators (E. coli and Bacteroidales genetic markers). Afterwards, the fate and transport of pathogens within the lake were simulated using a three-dimensional coupled hydrodynamic and microbiological model. This approach provided information on the contribution from different contamination sources to the pathogen concentrations at the water intake of a drinking water treatment plant. This approach addresses the limitations of monitoring and provides data for quantitative microbial risk assessment(QMRA) and risk management in the context of faecal contamination of surface drinking water sources.
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| 13. |
- Sokolova, Ekaterina, 1986, et al.
(författare)
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Water quality modelling: microbial risks associated with manure on pasture and arable land
- 2018
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1996-7829 .- 1477-8920. ; 16:4, s. 549-561
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Tidskriftsartikel (refereegranskat)abstract
- While agricultural activities, such as the application of manure on arable land and animal grazing on pastures, provide economic and environmental benefits, they may also pose microbial risks to water sources. The aim of this paper was to study the microbial fate and transport in an agricultural catchment and recipient water source through further development of the hydrological model HYPE. Hydrological modelling was combined with hydrodynamic modelling to simulate the fate and transport of Salmonella spp., verotoxin-producing Escherichia coli O157:H7 and Cryptosporidium parvum in an agricultural catchment of a drinking water source, Lake Vombsjön, in Sweden. This approach was useful to study the influence of different processes on the pathogen fate and transport, and to interpret the relative changes in the simulated concentrations. Sensitivity analysis indicated that the largest uncertainties in the model were associated with the estimation of pathogen loads, parameterisation of the pathogen processes, and simulation of partitioning between surface runoff and infiltration. The proposed modelling approach is valuable for assessing the relative effect of different risk-reducing interventions.
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| 14. |
- Vinnerås, Björn
(författare)
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Hygienic effects and gas production of plastic bio-digesters under tropical conditions
- 2009
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1477-8920 .- 1996-7829. ; 7, s. 590-596
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Tidskriftsartikel (refereegranskat)abstract
- Plastic plug-flow bio-digesters have been promoted as a good option for improved treatment of manure and wastewater in developing countries although minimal information has been published on their hygienic status. This bench-scale study replicates bio-digester conditions to evaluate the reduction of pathogen and indicator microorganisms at three different hydraulic retention times (HRT) in the anaerobic treatment of pig manures at 30 degrees C for 50 days. Results showed that physicochemical values differed between HRTs. Gas production efficiency was better for longer HRTs. The accumulated sludge at the reactor's base increased with longer HRT. Phages and bacteria examined were reduced, but none was completely eliminated. Log(10) reduction of bacteria ranged from 0.54 to 2.47. Phages ranged from 1.60 to 3.42. The reduction of organisms at HRT = 30 days was about one log(10) unit higher than HRT = 15 days and about two log(10) units higher than HRT = 3 days. The results indicate that the reduction of tested organisms increases with HRT. However the hygienic quality of the liquid effluent does not meet required quality values for surface and irrigation water. Longer HRTs are recommended to increase gas yield and achieve higher pathogen reduction. More barriers should be applied while handling bio-digester outputs to minimise risks to environmental and human health.
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| 15. |
- Yitayew, Berhanu, et al.
(författare)
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Carbapenemase-producing Aeromonas species isolated from the urban-impacted Akaki river in Ethiopia
- 2022
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1477-8920 .- 1996-7829. ; 20:6
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Tidskriftsartikel (refereegranskat)abstract
- Carbapenemase-producing Aeromonas species are an emerging health threat. This study aimed to determine carbapenemase-mediated resistance among Aeromonas isolates from the Akaki river, Ethiopia during the dry and wet seasons in 2019-2020. Antimicrobial susceptibility to carbapenems and cephalosporins was determined and carbapenemase production was confirmed. Of 163 isolates, the majority were human pathogens Aeromonas caviae (62), Aeromonas hydrophila (33) and Aeromonas veronii (49). These isolates were resistant to carbapenem and cephalosporin antibiotics, with the highest resistance to cefotaxime 86 (59.7%), ertapenem 71 (49.3%) and imipenem 65 (45.1%). Resistance to carbapenem antibiotics varied between species, where most A. veronii 37 (75.5%) and A. hydrophila 28 (84.8%) were resistant to imipenem, whereas all A.caviae were sensitive. A. veronii, A. caviae and A. hydrophila resistance to meropenem was 31 (63.3%), 3 (4.8%) and 19 (57.6%), respectively. Of isolates resistant to carbapenem, 82.1% A. hydrophila and 94.4% A. veronii were carbapenemase producers. Cephalosporin resistance also varied among the different species. The highest resistance to carbapenem antibiotics was in isolates collected during the wet season (p<0.05); however, it was not consistent across all classes of antibiotics tested. The rivers in megacities could be reservoirs of carbapenemase-producing Aeromonas spp.
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| 16. |
- Åström, Johan, 1977, et al.
(författare)
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Evaluation of the microbial risk reduction due to selective closure of the raw water intake before drinking water treatment
- 2007
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Ingår i: Journal of Water and Health. - 1996-7829 .- 1477-8920. ; 5:1, s. 81-97
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Tidskriftsartikel (refereegranskat)abstract
- Short-term peaks in pathogen concentrations may increase the risks for waterborne diseases considerably. In this study the occurrence of indicator organisms and pathogens in the river Göta älv at the raw water intake to Göteborg was evaluated and related to risk for drinking water consumption. About half of the 24 pathogen samples, taken during event and non-event conditions, were positive for at least one of the following: Cryptosporidium, Giardia, norovirus, enterovirus, Campylobacter and E. coli O157. Positive pathogen detects were often associated with heavy rainfalls and viruses with a sewage emergency discharge. The annualised probability of infection from this type of event was calculated from pathogen concentrations in a QMRA model. Given that the water intake is not closed, the risk given present water treatment seems to be acceptable for Giardia; however, it is at a borderline for Cryptosporidium and insufficient for noro- and enteroviruses. Present results emphasise the need for an appropriate intake regulation with respect to high pathogen loads, as the risk increases with time of exposure to pathogen contaminants. Rather than a threshold level on E. coli, reports on upstream microbial discharges are valuable for quick pathogen indications.
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| 17. |
- Åström, Johan, 1977, et al.
(författare)
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Identification and management of microbial contaminations in a surface drinking water source
- 2007
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Ingår i: Journal of Water and Health. - 1996-7829 .- 1477-8920. ; 5:1, s. 67-79
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Tidskriftsartikel (refereegranskat)abstract
- Microbial contamination of surface waters constitutes a health risk for drinking water consumers which may be lowered by closing the raw water intake. We have evaluated microbial discharge events reported in the river Göta älv, which is used for raw water supply to the city of Göteborg. Elevated levels of faecal indicator bacteria were observed during periods of closed raw water intake. High bacteria levels were, however, also occasionally detected during periods of open intake, probably as a result of microbial discharge far upstream in the river which may be difficult to predict and manage by closing the intake. Accumulated upstream precipitations, resulting in surface runoff and wastewater contaminations in the catchment, correlated positively with the levels of total coliforms, E. coli, intestinal enterococci and sulfite-reducing clostridia. Levels of faecal indicator organisms were negatively correlated to the water temperature due to enhanced survival at lower temperatures. Wastewater discharges from a municipality located just upstream of the water intake resulted in elevated E. coli concentrations downstream at the raw water intake for Göteborg. To improve the prediction of microbial contaminations within the river Göta älv, monitoring data on turbidity and upstream precipitation are of particular importance.
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| 18. |
- Åström, Johan, 1977, et al.
(författare)
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Short-term microbial release during rain events from on-site sewers and cattle in a surface water source
- 2013
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Ingår i: Journal of Water and Health. - : IWA Publishing. - 1477-8920 .- 1996-7829. ; 11:3, s. 430-442
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Tidskriftsartikel (refereegranskat)abstract
- The protection of drinking water from pathogens such as Cryptosporidium and Giardia requires an understanding of the short-term microbial release from faecal contamination sources in the catchment. Flow-weighted samples were collected during two rainfall events in a stream draining an area with on-site sewers and during two rainfall events in surface runoff from a bovine cattle pasture. Samples were analysed for human (BacH) and ruminant (BacR) Bacteroidales genetic markers through quantitative polymerase chain reaction (qPCR) and for sorbitol-fermenting bifidobacteria through culturing as a complement to traditional faecal indicator bacteria, somatic coliphages and the parasitic protozoa Cryptosporidium spp. and Giardia spp. analysed by standard methods. Significant positive correlations were observed between BacH, Escherichia coli, intestinal enterococci, sulphite-reducing Clostridia, turbidity, conductivity and UV254 in the stream contaminated by on-site sewers. For the cattle pasture, no correlation was found between any of the genetic markers and the other parameters. Although parasitic protozoa were not detected, the analysis for genetic markers provided baseline data on the short-term faecal contamination due to these potential sources of parasites. Background levels of BacH and BacR makers in soil emphasise the need to including soil reference samples in qPCR-based analyses for Bacteroidales genetic markers.
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| 19. |
- Gunnarsdottir, Maria J., et al.
(författare)
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Implementing risk-based approaches to improve drinking water quality in small water supplies in the Nordic region – barriers and solutions
- 2023
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Ingår i: Journal of Water and Health. - 1477-8920. ; 21:12, s. 1747-1760
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Tidskriftsartikel (refereegranskat)abstract
- Small water supplies face similar problems worldwide, regardless of ownership or management type. Non-compliance with water quality regulations is more frequent in small supplies than in large ones, as are waterborne disease outbreaks. The new EU Drinking Water Directive requires risk-based approach (RBA) to secure water safety as is recommended in the WHO's Guidelines for drinking water quality through ‘water safety plans’. This is already in regulation in the Nordic countries, although less used in small supplies. In this research, we explore the challenges, barriers and possible solutions to implementing RBA and improving compliance in small supplies. This was achieved by conducting and analysing interviews with 53 stakeholders from all 8 Nordic countries to produce recommendations for action by the different implicated actors. Our findings suggest the centrality of governmental policy, including support for continuous training, provision of simple RBA guidelines and increasing cooperation in the water sector. The Nordic experience reflects global challenges with small water supplies and the trend towards systematic preventive management epitomized in the framework for drinking water safety advocated by the World Health Organization since 2004.
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| 20. |
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| 21. |
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| 22. |
- Westrell, Therese, et al.
(författare)
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Drinking water consumption patterns in Sweden
- 2006
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Ingår i: Journal of Water and Health. - 1477-8920. ; 4:4, s. 511-522
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Tidskriftsartikel (refereegranskat)abstract
- Estimates on drinking water consumption are necessary in risk assessments on microbial hazardsin drinking water. Large differences in consumption habits between countries have beenreported. In order to establish estimates for the Swedish population, water consumption datafrom a waterborne outbreak investigation (157 people), a small water consumption study(75 people) and a large study on health and environmental factors (10,957 people) were analysed.A lognormal distribution for the daily direct/cold water intake in litres with m¼20.299 ands ¼ 0.570 was fitted to the quantitative data, representing the general population. The averagedaily consumption of tap water as plain drinking water and as heated tap water, e.g. in coffeeand tea, was 0.86 ^ 0.48 l and 0.94 ^ 0.69 l, respectively. Women consumed more cold tap waterthan did men, while men appeared to have a higher consumption of heated tap water. Cold tapwater intake was highest in the oldest age group, ($70 years). The consumption of bottled waterwas very low (mean 0.06 l/d) when compared to other countries.
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| 23. |
- Yu, Maria, et al.
(författare)
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Impact of sample acidification and extract storage on hormone receptor-mediated and oxidative stress activities in wastewater
- 2024
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Ingår i: Journal of Water and Health. - 1477-8920. ; 22, s. 169-182
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Tidskriftsartikel (refereegranskat)abstract
- An underemphasized aspect of sampling strategies in effect-based in vitro testing is to determine suitable collection and preparation techniques. In the current study, the impact of sample acidification on bioactivities was assessed using in vitro bioassays for hormone receptor-mediated effects (estrogen receptor [ER] and androgen receptor [AR]) and the oxidative stress response (Nrf2 activity). Sampling was conducted at a recently upgraded Swedish wastewater treatment plant. Future plans for the treated wastewater include reuse for irrigation or as a drinking water source. In the AR and Nrf2 assays, acidification decreased bioactivities in the wastewater influent sample extracts, whereas acidification increased bioactivities following further treatment (disc filtration). In the ER assay, acidification had no impact on the observed bioactivities in the sample extracts. A secondary objective of the study was to assess the stability of the sample extracts over time. Lower activities were detected in the ER and AR assays in all extracts after storage for approximately 1 year. Nrf2 activities did not decrease over time, but rather increased in some of the acidified sample extracts. Overall, the findings suggest that sampling strategies involving acidification may need to be tailored depending on the selected bioassay(s) and the type of wastewater treatments being assessed.
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