scholarly journals Microbial source tracking of fecal contamination in Laguna Lake, Philippines using the library-dependent method, rep-PCR

2021 ◽  
Author(s):  
Laurice Beatrice Raphaelle O. dela Peña ◽  
Kevin L. Labrador ◽  
Mae Ashley G. Nacario ◽  
Nicole R. Bolo ◽  
Windell L. Rivera
Keyword(s):  
Surface Waters ◽  
Fecal Contamination ◽  
Microbial Source Tracking ◽  
The Philippines ◽  
Source Tracking ◽  
Source Attribution ◽  
Monitoring Methods ◽  
K Nearest Neighbors ◽  
Fecal Indicator ◽  
Laguna Lake

Abstract Laguna Lake is an economically important resource in the Philippines, with reports of declining water quality due to fecal pollution. Currently, monitoring methods rely on counting fecal indicator bacteria, which does not supply information on potential sources of contamination. In this study, we predicted sources of Escherichia coli in lake stations and tributaries by establishing a fecal source library composed of rep-PCR DNA fingerprints of human, cattle, swine, poultry, and sewage samples (n = 1,408). We also evaluated three statistical methods for predicting fecal contamination sources in surface waters. Random forest (RF) outperformed k-nearest neighbors and discriminant analysis of principal components in terms of average rates of correct classification in two- (84.85%), three- (82.45%), and five-way (74.77%) categorical splits. Overall, RF exhibited the most balanced prediction, which is crucial for disproportionate libraries. Source tracking of environmental isolates (n = 332) revealed the dominance of sewage (47.59%) followed by human sources (29.22%), poultry (12.65%), swine (7.23%), and cattle (3.31%) using RF. This study demonstrates the promising utility of a library-dependent method in augmenting current monitoring systems for source attribution of fecal contamination in Laguna Lake. This is also the first known report of microbial source tracking using rep-PCR conducted in surface waters of the Laguna Lake watershed.

scholarly journals Microbial Source-Tracking Reveals Origins of Fecal Contamination in a Recovering Watershed

Water ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2162 ◽  
Author(s):  
Hyatt Green ◽  
Daniel Weller ◽  
Stephanie Johnson ◽  
Edward Michalenko
Keyword(s):  
Urban Areas ◽  
Bacterial Contamination ◽  
Fecal Contamination ◽  
Microbial Source Tracking ◽  
Mitigation Strategies ◽  
Source Tracking ◽  
Chemical Parameters ◽  
Fecal Indicator ◽  
Combined Sewer ◽  
Rain Events

Fecal contamination of waterbodies due to poorly managed human and animal waste is a pervasive problem that can be particularly costly to address, especially if mitigation strategies are ineffective at sufficiently reducing the level of contamination. Identifying the most worrisome sources of contamination is particularly difficult in periurban streams with multiple land uses and requires the distinction of municipal, agricultural, domestic pet, and natural (i.e., wildlife) wastes. Microbial source-tracking (MST) methods that target host-specific members of the bacterial order Bacteroidales and others have been used worldwide to identify the origins of fecal contamination. We conducted a dry-weather study of Onondaga Creek, NY, where reducing fecal contamination has been approached mainly by mitigating combined sewer overflow events (CSOs). Over three sampling dates, we measured in-stream concentrations of fecal indicator bacteria; MST markers targeting human, ruminant, and canine sources; and various physical–chemical parameters to identify contaminants not attributable to CSOs or stormwater runoff. We observed that despite significant ruminant inputs upstream, these contaminants eventually decayed and/or were diluted out and that high levels of urban bacterial contamination are most likely due to failing infrastructure and/or illicit discharges independent of rain events. Similar dynamics may control other streams that transition from agricultural to urban areas with failing infrastructure.

scholarly journals Microbial Source Tracking of Fecal Indicating Bacteria in Coral Reef Waters, Recreational Waters, and Groundwater of Saipan by Real-Time Quantitative PCR

2021 ◽  
Vol 11 ◽  
Author(s):  
Christopher Sinigalliano ◽  
Kiho Kim ◽  
Maribeth Gidley ◽  
Kathy Yuknavage ◽  
Karen Knee ◽  
...  
Keyword(s):  
Surface Waters ◽  
Coastal Waters ◽  
Fecal Contamination ◽  
Microbial Source Tracking ◽  
Source Tracking ◽  
Gene Marker ◽  
Primary Input ◽  
Gene Markers ◽  
Nitrogen Inputs ◽  
Microbial Contaminants

The Commonwealth of the Northern Mariana Islands (CNMI) recently identified the need to improve its capacity for detecting and tracking land-based sources of pollution (LBSP) in coastal waters, particularly microbial contaminants like fecal indicator bacteria (FIB). Reported here is a baseline study of a suite of host-specific FIB microbial source tracking (MST) markers in the coastal shoreline and reef waters around the island of Saipan. Three sampling campaigns were conducted in September 2017, March 2018, and August 2018. Samples were collected from the nearshore surface waters of Saipan, the reef waters of Saipan Lagoon, and groundwater from beaches along the Saipan Lagoon shoreline. Measurements of submarine groundwater discharge (SGD) into nearshore waters and isotopic source tracking of nitrogen inputs were conducted concurrently with MST. Environmental DNA was extracted from the samples and analyzed by quantitative polymerase chain reaction (qPCR) for MST gene markers of fecal Bacteroidales specifically associated with humans, dogs, cows, and pigs, and for an MST gene marker of Catellicoccus associated with seabirds. MST assessments were combined with local knowledge, assessments of sanitary infrastructure, and routine watershed surveys. This study identified hotspots of human FIB along the western Saipan Lagoon shoreline in both surface waters and groundwater, plus another hotspot of human FIB at a popular tourist bathing area known as the Grotto. FIB hotspots on the Lagoon shoreline coincided with areas of high SGD and nitrogen isotopic data indicating sewage-derived N inputs. It appears that faulty sanitary infrastructure may be contributing to inputs to Saipan Lagoon, while bather shedding is likely a primary input for the Grotto area. Moderate levels of dog fecal contamination were common and widespread across the island. High levels of seabird fecal contamination were more random, both spatially and temporally, and mostly concentrated along the less developed northeast region of Saipan. No significant levels of cow or pig fecal marker were detected in coastal water samples. This study provides demonstration and establishment of analytical capacity to resource management in CNMI for MST technology to aid in trouble-shooting water quality issues involving land-based sources of microbial contaminants to CNMI coastal waters.

scholarly journals Library-independent source tracking of fecal contamination in selected stations and tributaries of Laguna Lake, Philippines

2021 ◽  
Author(s):  
Joseth Jermaine M. Abello ◽  
Gicelle T. Malajacan ◽  
Kevin L. Labrador ◽  
Mae Ashley G. Nacario ◽  
Luiza H. Galarion ◽  
...  
Keyword(s):  
Water Quality ◽  
Management Practices ◽  
Fecal Contamination ◽  
The Philippines ◽  
Source Tracking ◽  
Lake Ecology ◽  
Heat Stable ◽  
Industrial Complexes ◽  
Laguna Lake

Abstract Laguna Lake is the largest inland freshwater body in the Philippines. Although it is classified to be usable for agricultural and recreational purposes by the country's Department of Environment and Natural Resources (DENR), studies looking at lake ecology revealed severe fecal contamination which contributes to the deterioration of water quality. Determining the sources of fecal contamination is necessary for lake protection and management. This study utilized a library-independent method of microbial source tracking (LIM-MST) to identify sources of fecal contamination in selected Laguna Lake stations and tributaries. Genetic markers of the host-associated Escherichia coli, heat-labile toxin (LTIIA) and heat-stable II (STII), were used to identify cattle and swine fecal contaminations, respectively. Meanwhile, human mitochondrial DNA (mtDNA) was used to identify human fecal contamination. Results identified the presence of agricultural and human fecal contamination in Laguna Lake Stations 1 and 5, Mangangate River, and Alabang River. The selected sites are known to be surrounded by residential and industrial complexes, and most of their discharges find their way into the lake. The identification of the specific sources of fecal contamination will guide management practices that aim to regulate the discharges in order to improve the water quality of Laguna Lake.

Multi-Year Microbial Source Tracking Study Characterizing Fecal Contamination in an Urban Watershed

2017 ◽  
Vol 89 (2) ◽  
pp. 127-143 ◽  
Author(s):  
Rebecca N. Bushon ◽  
Amie M.G. Brady ◽  
Eric D. Christensen ◽  
Erin A. Stelzer
Keyword(s):  
Fecal Contamination ◽  
Microbial Source Tracking ◽  
Source Tracking ◽  
Urban Watershed

scholarly journals Evaluation of Two Library-Independent Microbial Source Tracking Methods To Identify Sources of Fecal Contamination in French Estuaries

2007 ◽  
Vol 73 (15) ◽  
pp. 4857-4866 ◽  
Author(s):  
Michèle Gourmelon ◽  
Marie Paule Caprais ◽  
Raphaël Ségura ◽  
Cécile Le Mennec ◽  
Solen Lozach ◽  
...  
Keyword(s):  
Water Samples ◽  
Fecal Contamination ◽  
Microbial Source Tracking ◽  
Source Tracking ◽  
Rrna Gene ◽  
Specific Marker ◽  
Gene Markers ◽  
High Level ◽  
Bird Feces

ABSTRACT In order to identify the origin of the fecal contamination observed in French estuaries, two library-independent microbial source tracking (MST) methods were selected: (i) Bacteroidales host-specific 16S rRNA gene markers and (ii) F-specific RNA bacteriophage genotyping. The specificity of the Bacteroidales markers was evaluated on human and animal (bovine, pig, sheep, and bird) feces. Two human-specific markers (HF183 and HF134), one ruminant-specific marker (CF193′), and one pig-specific marker (PF163) showed a high level of specificity (>90%). However, the data suggest that the proposed ruminant-specific CF128 marker would be better described as an animal marker, as it was observed in all bovine and sheep feces and 96% of pig feces. F RNA bacteriophages were detected in only 21% of individual fecal samples tested, in 60% of pig slurries, but in all sewage samples. Most detected F RNA bacteriophages were from genotypes II and III in sewage samples and from genotypes I and IV in bovine, pig, and bird feces and from pig slurries. Both MST methods were applied to 28 water samples collected from three watersheds at different times. Classification of water samples as subject to human, animal, or mixed fecal contamination was more frequent when using Bacteroidales markers (82.1% of water samples) than by bacteriophage genotyping (50%). The ability to classify a water sample increased with increasing Escherichia coli or enterococcus concentration. For the samples that could be classified by bacteriophage genotyping, 78% agreed with the classification obtained from Bacteroidales markers.

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