The inhibitory effect of ozone and hydrogen peroxide (HP) on urea hydrolysis in stored urine was investigated and compared. Ozone showed less effect on urea hydrolysis due to the complicated composition of urine (including a large amount of urease-producing bacteria) and bacteria regeneration. Ozone concentration and total heterotrophic bacteria analysis demonstrated that residual ozone ...
Genetic markers derived from Bacteroidales spp. have been proposed as promising indicators for fecal contamination in the water environment. However, little is known about the persistency of Bacteroidales spp. 16S rRNA genetic markers in the natural environment, which hampers the precise identification of fecal contamination sources. In this study, the persistency of human-specific ...
Exposure to fecal contamination is a leading cause of childhood infectious diseases in low- and middle-income countries. Low-quality sanitation infrastructure and inadequate maintenance can make on-site solutions prone to spillage, exposing children to sewage. This paper uses a unique dataset with independent verification of sewage in and around the parcels of more than 20,000 houses with ...
Fluctuation of bacteriophage and Escherichia coli densities in naturally developed riverbed biofilms were investigated for a 1-year period. E. coli ranged from 1,500 to 15,500 most probable number (MPN)/100 mL and from 580 to 18,500 MPN/cm2 in the main channel in the river water and biofilms, respectively. However, the fluctuations were much greater in the tributary, ranging from 0.8 to 100 ...
Rapid urbanization in low-resource countries has led to a growing sanitation crisis, with widespread fecal contamination and risk of adverse health outcomes. Understanding how to change sanitation behaviors and reduce exposure to fecal contamination is central to Sustainable Development Goal 6. This study examines behavioral influences on fecal contamination in six low-resource neighborhoods ...
As a representative urban stream in Korea, the Gwangju (GJ) stream suffers from chronic fecal contamination. In this study, to characterize levels of fecal pollution in the GJ stream, the monthly monitoring data for seven years (from 2001 to 2007) and the hourly monitoring data from two field experiments were examined with respect to seasonal/daily variations and spatial distribution under wet ...
I write about pest control for a living, so I have described mice and rats and the problems they cause in detail many times. But it became a whole different story when there was a mouse in MY house. A few months ago I was sitting watching television, when out of the corner of my eye I see movement. I watch in disbelief as a full-grown house mouse runs along the edge of my living room wall and ...
Microbial indicators such as heterotrophic bacteria, total coliforms, and Escherichia coli in naturally developed riverbed biofilms were investigated. Pebbles covered with natural biofilm were sampled directly from the riverbed at sampling stations ranging from the upstream region within a quasi-national park to the midstream in the urban district. Heterotrophic bacteria densities in biofilm ...
Adenoviruses (AdV) are related to respiratory and gastrointestinal diseases in animals and human beings. Their wide genetic diversity in water bodies and their resistance to environmental conditions allow the use of AdV as a reliable marker for detection of fecal contamination. In this work, the diversity of AdV along Belo Stream – in the city of Caxias do Sul, Rio Grande do Sul, Brazil – was ...
A prospective cohort epidemiological pilot study was performed at three tropical beaches with point- and non-point-sources of fecal pollution to characterize the risk of illness among swimmers and non-swimmers. There was an increased risk of illness in swimmers as compared to non-swimmers, even when waters met current microbial standards for recreational water quality. Illnesses included ...
Received for publication April 24, 2009. A linkage between Cladophora mats and exceedances of recreational water quality criteria has been suggested, but not directly studied. This study investigates the spatial and temporal association between Escherichia coli concentrations within and near Cladophora mats at two northwestern Lake Michigan beaches in Door County, Wisconsin. Escherichia coli ...
Temporal variability in the gastrointestinal flora of animals impacting water resources with fecal material can be one of the factors producing low source identification rates when applying microbial source tracking (MST) methods. Understanding how bacterial species and genotypes vary over time is highly relevant when the fecal material used to create a source library is collected under very ...
The co-residence of bacteriophages and their bacterial hosts in humans, animals, and environmental sources directed the use of bacteriophages to track the origins of the pathogenic bacteria that can be found in contaminated water. The objective of this study was to enumerate bacteriophages of Aeromonas caviae (AecaKS148), Enterobacter sp. (EnspKS513), and Klebsiella pneumoniae (KlpnKS648) in ...
Untitled Document Culture-independent fecal source tracking methods have many potential advantages over library-dependent, isolate-culture methods, but they have been subjected to limited testing. The purpose of this study was to compare culture-independent, library-independent methods of fecal source tracking. Five laboratories analysed identical sets of aqueous samples that ...
Cladophora in the Great Lakes grows rapidly during the warm summer months, detaches, and becomes free-floating mats as a result of environmental conditions, eventually becoming stranded on recreational beaches. Cladophora provides protection and nutrients, which allow enteric bacteria such as Escherichia coli, enterococci, Shigella, Campylobacter, and Salmonella to persist and potentially regrow ...
This study aims to apply fecal sterols as a chemical indicator to track feces contamination sources in the canals in Bangkok. The sewage and canal sediments were examined during the dry season. Fecal sterols in the canals were evaluated over a one-year period (2011–2012) for the selected sterol compounds. Several factors including season, canal water levels, rainfall data, and sewage were ...
Several beaches within the Toronto region area of concern have persistent issues with fecal contamination, causing a beach beneficial use impairment (BUI). In this study, Escherichia coli, including ampicillin-resistant strains, were enumerated via culturable and quantitative polymerase chain reaction (qPCR) methods. Microbial source tracking (MST) markers (for general Bacteroidales, human, ...
Hepatitis E virus (HEV) is transmitted via the fecal–oral route and has been recognized as a common source of large waterborne outbreaks involving contaminated water in developing countries. Thus, there is the need to produce experimental data on the disinfection kinetics of HEV by chlorine in water samples with diverse levels of fecal contamination. Here, the inactivation of HEV and ...
Splash parks have been associated with infectious disease outbreaks as a result of exposure to poor water quality. To be able to protect public health, risk factors were identified that determine poor water quality. Samples were taken at seven splash parks where operators were willing to participate in the study. Higher concentrations of Escherichia coli were measured in water of splash parks ...
The risk of water contamination by fecal bacteria may be increased if a watershed includes areas where feces accumulate as a result of specific land uses, such as areas where owners frequently exercise dogs. This study examined the effects of a year-round dog exercise area in the Burke Creek Recreational Area (BCRA) in the arid alpine environment of Stateline, Nevada. Burke Creek drains a small, ...