Effect of pipe material and disinfectant on active bacterial communities in drinking water and biofilms.

Aims: We investigated the combined effects of pipe materials and disinfection chemicals on bacterial community and its active RNA fraction in water and biofilms in a pilot-scale premise plumbing system.

Methods And Results: The changes in bacterial communities were studied within four pipelines using copper and cross-linked polyethylene (PEX) pipe with chlorine or chloramine disinfection. The total and active bacterial communities and the presence of opportunistic pathogens (Legionella spp.

Campylobacter species, Salmonella serotypes and ribosomal RNA-based fecal source tracking in the Kokemäki River watershed.

Fecal contamination of surface water compromises the usability of surface water for drinking water production due to an increase in human health risks. In this study, we collected surface water samples for two years from the Kokemäki River (Finland). The downstream river stretch is used for feeding production of artificial ground water for a major drinking water treatment plant.

Composition of active bacterial communities and presence of opportunistic pathogens in disinfected and non-disinfected drinking water distribution systems in Finland.

Many factors, including microbiome structure and activity in the drinking water distribution system (DWDS), affect the colonization potential of opportunistic pathogens. The present study aims to describe the dynamics of active bacterial communities in DWDS and identify the factors that shape the community structures and activity in the selected DWDSs. Large-volume drinking water and hot water, biofilm, and water meter deposit samples were collected from five DWDSs.

A comparative analysis employing a gene- and genome-centric metagenomic approach reveals changes in composition, function, and activity in waterworks with different treatment processes and source water in Finland.

The emergence and development of next-generation sequencing technologies (NGS) has made the analysis of the water microbiome in drinking water distribution systems (DWDSs) more accessible and opened new perspectives in microbial ecology studies. The current study focused on the characterization of the water microbiome employing a gene- and genome-centric metagenomic approach to five waterworks in Finland with different raw water sources, treatment methods, and disinfectant. The microbial communities exhibit a distribution pattern of a few dominant taxa and a large representation of low-abundance bacterial species.

Monitoring groundwater quality with real-time data, stable water isotopes, and microbial community analysis: A comparison with conventional methods.

Groundwater provides much of the world's potable water. Nevertheless, groundwater quality monitoring programmes often rely on a sporadic, slow, and narrowly focused combination of periodic manual sampling and laboratory analyses, such that some water quality deficiencies go undetected, or are detected too late to prevent adverse consequences. In an effort to address this shortcoming, we conducted enhanced monitoring of untreated groundwater quality over 12 months (February 2019-February 2020) in four shallow wells supplying potable water in Finland.

Effects of temperature and light exposure on the decay characteristics of fecal indicators, norovirus, and Legionella in mesocosms simulating subarctic river water.

Knowledge of the decay characteristics of health-related microbes in surface waters is important for modeling the transportation of waterborne pathogens and for assessing their public health risks. Although water temperature and light exposure are major factors determining the decay characteristics of enteric microbes in surface waters, such effects have not been well studied in subarctic surface waters. This study comprehensively evaluated the effect of temperature and light on the decay characteristics of health-related microbes [Escherichia coli, enterococci, microbial source tracking markers (GenBac3 & HF183 assays), coliphages (F-specific and somatic), noroviruses GII and Legionella spp.

Detection and quantification of SARS-CoV-2 RNA in wastewater influent in relation to reported COVID-19 incidence in Finland.

Wastewater-based surveillance is a cost-effective concept for monitoring COVID-19 pandemics at a population level. Here, SARS-CoV-2 RNA was monitored from a total of 693 wastewater (WW) influent samples from 28 wastewater treatment plants (WWTP, N = 21-42 samples per WWTP) in Finland from August 2020 to May 2021, covering WW of ca. 3.

Bacterial Genes Encoding Resistance Against Antibiotics and Metals in Well-Maintained Drinking Water Distribution Systems in Finland.

Information on the co-occurrence of antibiotic resistance genes (ARGs) and metal resistance genes (MRGs) among bacterial communities in drinking water distribution systems (DWDSs) is scarce. This study characterized ARGs and MRGs in five well-maintained DWDSs in Finland. The studied DWDSs had different raw water sources and treatment methods.

Surface Water Intrusion, Land Use Impacts, and Bacterial Community Composition in Shallow Groundwater Wells Supplying Potable Water in Sparsely Populated Areas of a Boreal Region.

Rural communities often rely on groundwater for potable water supply. In this study, untreated groundwater samples from 28 shallow groundwater wells in Finland (<10 m deep and mostly supplying untreated groundwater to <200 users in rural areas) were assessed for physicochemical water quality, stable water isotopes, microbial water quality indicators, host-specific microbial source tracking (MST) markers, and bacterial community composition, activity, and diversity (using amplicon sequencing of the 16S rRNA gene and 16S rRNA). Indications of surface water intrusion were identified in five wells, and these indications were found to be negatively correlated, overall, with bacterial alpha diversity (based on amplicon sequencing of the 16S rRNA gene).

Phage Biocontrol of in Water.

Bacteriophage control of harmful or pathogenic bacteria has aroused growing interest, largely due to the rise of antibiotic resistance. The objective of this study was to test phages as potential agents for the biocontrol of an opportunistic pathogen in water. Two bacteriophages (vB_PaeM_V523 and vB_PaeM_V524) were isolated from wastewater and characterized physically and functionally.

Diverse and active archaea communities occur in non-disinfected drinking water systems-Less activity revealed in disinfected and hot water systems.

The knowledge about the members of active archaea communities in DWDS is limited. The current understanding is based on high-throughput 16S ribosomal RNA gene (DNA-based) amplicon sequencing that reveals the diversity of active, dormant, and dead members of the prokaryote (bacteria, archaea) communities. The sequencing primers optimized for bacteria community analysis may underestimate the share of the archaea community.

Bacterial diversity and predicted enzymatic function in a multipurpose surface water system - from wastewater effluent discharges to drinking water production.

Background: Rivers and lakes are used for multiple purposes such as for drinking water (DW) production, recreation, and as recipients of wastewater from various sources. The deterioration of surface water quality with wastewater is well-known, but less is known about the bacterial community dynamics in the affected surface waters. Understanding the bacterial community characteristics -from the source of contamination, through the watershed to the DW production process-may help safeguard human health and the environment.

The detection and stability of the SARS-CoV-2 RNA biomarkers in wastewater influent in Helsinki, Finland.

Wastewater-based surveillance of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is used to monitor the population-level prevalence of the COVID-19 disease. In many cases, due to lockdowns or analytical delays, the analysis of wastewater samples might only be possible after prolonged storage. In this study, the effect of storage conditions on the RNA copy numbers of the SARS-CoV-2 virus in wastewater influent was studied and compared to the persistence of norovirus over time at 4 °C, -20 °C, and -75 °C using the reverse-transcription quantitative PCR (RT-qPCR) assays E-Sarbeco, N2, and norovirus GII.

Potential and limitations of a pilot-scale drinking water distribution system for bacterial community predictive modelling.

Waterborne disease outbreaks are a persistent and serious threat to public health according to reported incidents across the globe. Online drinking water quality monitoring technologies have evolved substantially and have become more accurate and accessible. However, using online measurements alone is unsuitable for detecting microbial regrowth, potentially including harmful species, ahead of time in the distribution systems.

Two Drinking Water Outbreaks Caused by Wastewater Intrusion Including Sapovirus in Finland.

Drinking water outbreaks occur worldwide and may be caused by several factors, including raw water contamination, treatment deficiencies, and distribution network failure. This study describes two drinking water outbreaks in Finland in 2016 (outbreak I) and 2018 (outbreak II). Both outbreaks caused approximately 450 illness cases and were due to drinking water pipe breakage and subsequent wastewater intrusion into the distribution system.

Active eukaryotes in drinking water distribution systems of ground and surface waterworks.

Background: Eukaryotes are ubiquitous in natural environments such as soil and freshwater. Little is known of their presence in drinking water distribution systems (DWDSs) or of the environmental conditions that affect their activity and survival.

Methods: Eukaryotes were characterized by Illumina high-throughput sequencing targeting 18S rRNA gene (DNA) that estimates the total community and the 18S rRNA gene transcript (RNA) that is more representative of the active part of the community.

Persistent Norovirus Contamination of Groundwater Supplies in Two Waterborne Outbreaks.

Microbiological contamination of groundwater supplies causes waterborne outbreaks worldwide. In this study, two waterborne outbreaks related to microbiological contamination of groundwater supplies are described. Analyses of pathogenic human enteric viruses (noroviruses and adenoviruses), fecal bacteria (Campylobacter spp.

Persistence of Norovirus GII Genome in Drinking Water and Wastewater at Different Temperatures.

Human norovirus (NoV) causes waterborne outbreaks worldwide suggesting their ability to persist and survive for extended periods in the environment. The objective of this study was to determine the persistence of the NoV GII genome in drinking water and wastewater at three different temperatures (3 °C, 21 °C, and 36 °C). The persistence of two NoV GII inoculums (extracted from stool) and an indigenous NoV GII were studied.

On-line detection of Escherichia coli intrusion in a pilot-scale drinking water distribution system.

Improvements in microbial drinking water quality monitoring are needed for the better control of drinking water distribution systems and for public health protection. Conventional water quality monitoring programmes are not always able to detect a microbial contamination of drinking water. In the drinking water production chain, in addition to the vulnerability of source waters, the distribution networks are prone to contamination.

Sand filters for removal of microbes and nutrients from wastewater during a one-year pilot study in a cold temperate climate.

Onsite wastewater treatment systems (OWTS) are recognised as potential threats to groundwater or other water environments subject to discharged effluents. In this study, the microbiological and nutrient removal properties of three different pilot-scale sand filters (SFs) were followed over a one-year period. Moreover, a separate phosphorus removal unit was tested for six months.

Microbial reduction in wastewater treatment using Fe(3+) and Al(3+) coagulants and PAA disinfectant.

Wastewater is an important source of pathogenic enteric microorganisms in surface water and a major contaminating agent of drinking water. Although primary and secondary wastewater treatments reduce the numbers of microorganisms in wastewater, significant numbers of microbes can still be present in the effluent. The aim of this study was to test the feasibility of tertiary treatment for municipal wastewater treatment plants (WWTPs) using PIX (FeCl3) or PAX (AlCl3) coagulants and peracetic acid (PAA) the disinfectant to reduce microbial load in effluent.

Drinking water quality and formation of biofilms in an office building during its first year of operation, a full scale study.

Complex interactions existing between water distribution systems' materials and water can cause a reduction in water quality and unwanted changes in materials, aging or corrosion of materials and formation of biofilms on surfaces. Substances leaching from pipe materials and water fittings, as well as the microbiological quality of water and formation of biofilms were evaluated by applying a Living Lab theme i.e.

Suitability of optical, physical and chemical measurements for detection of changes in bacterial drinking water quality.

In this study, different optical, physical and chemical measurements were tested for their capacity to detect changes in water quality. The tests included UV-absorbance at 254 nm, absorbance at 420 nm, turbidity, particle counting, temperature, pH, electric conductivity (EC), free chlorine concentration and ATP concentration measurements. Special emphasis was given to investigating the potential for measurement tools to detect changes in bacterial concentrations in drinking water.

Manual faucets induce more biofilms than electronic faucets.

Electronic faucets (types E1 and E2) and manual (M) faucets were studied for microbial quality, i.e., biomass and pathogenic microbes of biofilms in the faucet aerator, the water, and the outer surface of faucet in a hospital in Finland.