An official website of the United States government
A sanitized drinking water supply is an unconditional requirement for public health and the overall prosperity of humanity. Potential microbial and chemical contaminants of drinking water have been identified by a joint effort between the World Health Organization (WHO) and the United Nations Children’s Fund (UNICEF), who together establish guidelines that define, in part, that the presence of Escherichia coli (E. coli) in drinking water is an indication of inadequate sanitation and a significant health risk. As E. coli is a nearly ubiquitous resident of mammalian gastrointestinal tracts, no detectable counts in 100 mL of drinking water is the standard used worldwide as an indicator of sanitation. The currently accepted EPA method relies on filtration, followed by growth on selective media, and requires 24–48 h from sample to results. In response, we developed a rapid bacteriophage-based detection assay with detection limit capabilities comparable to traditional methods in less than a quarter of the time. We coupled membrane filtration with selective enrichment using genetically engineered bacteriophages to identify less than 20 colony forming units (CFU) E. coli in 100 mL drinking water within 5 h. The combination of membrane filtration with phage infection produced a novel assay that demonstrated a rapid, selective, and sensitive detection of an indicator organism in large volumes of drinking water as recommended by the leading world regulatory authorities.
more »
« less
This content will become publicly available on January 1, 2026
Can Reuse of Stormwater Detention Pond Water Meet Community Urban Agriculture Needs?
Urbanization and population growth in coastal communities increase demands on local food and water sectors. Due to this, urban communities are reimagining stormwater pond infrastructure, asking whether the stormwater can be used to irrigate food and grow fish for local consumption. Studies exploring this feasibility are limited in the literature. Driven by a community’s desire to co-locate community gardens with stormwater pond spaces, this research monitored the water quality of a 23.4-hectare stormwater pond located in East Tampa, Florida over one year using the grab sample technique and compared the results with U.S. Environmental Protection Agency (EPA) reuse recommendations, EPA national recommended water quality criteria for aquatic life, and human health. pH and conductivity levels were acceptable for irrigating crops. Heavy metal (arsenic, cadmium, copper, lead, and zinc) concentrations were below the maximum recommended reuse levels (100, 10, 200, 5000 and 2000 µg/L, respectively), while zinc and lead were above the criteria for aquatic life (120 and 2.5 µg/L, respectively). E. coli concentrations ranged from 310 to greater than 200,000 MPN/100 mL, above the 0 CFU/100 mL irrigation requirements for raw food consumption and 200 CFU/100 mL requirements for commercial food processing. Synthetic organic compounds also exceeded criteria for human health.
more »
« less
- PAR ID:
- 10593550
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Sustainability
- Volume:
- 17
- Issue:
- 2
- ISSN:
- 2071-1050
- Page Range / eLocation ID:
- 523
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
Herrera, Manuel (Ed.)Three buildings that were repurposed for use as an elementary school were shutdown for three months in response to the pandemic. Building cold and hot water quality was monitored before reopening to detect and resolve chemical and microbiological problems. The authors collected first draw pre-flush and post-flush water samples. First draw water samples did not contain detectable disinfectant residual, but nickel and lead sometimes exceeded the health-based action limits for cold water (max. 144 μg Ni/L, 3.4 μg Pb/L). Stagnant cold water at a bathroom sink (188 MPN/100 mL) and drinking water fountain (141.6 MPN/100 mL), in the same building, exceeded the L . pneumophila thresholds advised by the World Health Organization (WHO) (10 CFU/mL) and American Industrial Hygiene Association (AIHA) (100 CFU/mL). Fixture flushing was conducted to remove cold and hot stagnant water and no L . pneumophila was detected immediately after flushing. Two weeks after no subsequent building water use, chemical and microbiological contaminant levels were found to be similar to levels prior to flushing with one exception. The maximum L . pneumophila level (kitchen sink, hot water: 61.1 MPN/100 mL) was found in a different building than the prior maximum detections. No repeat positive locations for L . pneumophila were found during the second visit, but new fixtures were positive the organism. When this study was conducted no evidence-based guidelines for plumbing recommissioning were available. A single plumbing flush reduced heavy metal and L . pneumophila levels below WHO and AIHA thresholds in all three buildings. Additional work is needed to examine the role of building size, type and plumbing design on fixture water quality in shutdown buildings.more » « less
-
Abstract Water quality monitoring is relevant for protecting the designated, or beneficial uses, of water such as drinking, aquatic life, recreation, irrigation, and food supply that support the economy, human well-being, and aquatic ecosystem health. Managing finite water resources to support these designated uses requires information on water quality so that managers can make sustainable decisions. Chlorophyll- a (chl- a , µg L −1 ) concentration can serve as a proxy for phytoplankton biomass and may be used as an indicator of increased anthropogenic nutrient stress. Satellite remote sensing may present a complement to in situ measures for assessments of water quality through the retrieval of chl- a with in-water algorithms. Validation of chl- a algorithms across US lakes improves algorithm maturity relevant for monitoring applications. This study compares performance of the Case 2 Regional Coast Colour (C2RCC) chl- a retrieval algorithm, a revised version of the Maximum-Peak Height (MPH (P) ) algorithm, and three scenarios merging these two approaches. Satellite data were retrieved from the MEdium Resolution Imaging Spectrometer (MERIS) and the Ocean and Land Colour Instrument (OLCI), while field observations were obtained from 181 lakes matched with U.S. Water Quality Portal chl- a data. The best performance based on mean absolute multiplicative error (MAE mult ) was demonstrated by the merged algorithm referred to as C 15 −M 10 (MAE mult = 1.8, bias mult = 0.97, n = 836). In the C 15 −M 10 algorithm, the MPH (P) chl- a value was retained if it was > 10 µg L −1 ; if the MPH (P) value was ≤ 10 µg L −1 , the C2RCC value was selected, as long as that value was < 15 µg L −1 . Time-series and lake-wide gradients compared against independent assessments from Lake Champlain and long-term ecological research stations in Wisconsin were used as complementary examples supporting water quality reporting requirements. Trophic state assessments for Wisconsin lakes provided examples in support of inland water quality monitoring applications. This study presents and assesses merged adaptations of chl- a algorithms previously reported independently. Additionally, it contributes to the transition of chl- a algorithm maturity by quantifying error statistics for a number of locations and times.more » « less
-
Bacterial contamination in food-processing facilities is a critical issue that leads to outbreaks compromising the integrity of the food supply and public health. We developed a label-free and rapid electrochemical biosensor for Listeria monocytogenes detection using a new one-step simultaneous sonoelectrodeposition of platinum and chitosan (CHI/Pt) to create a biomimetic nanostructure that actuates under pH changes. The XPS analysis shows the effective co-deposition of chitosan and platinum on the electrode surface. This deposition was optimized to enhance the electroactive surface area by 11 times compared with a bare platinum–iridium electrode (p < 0.05). Electrochemical behavior during chitosan actuation (pH-stimulated osmotic swelling) was characterized with three different redox probes (positive, neutral, and negative charge) above and below the isoelectric point of chitosan. These results showed that using a negatively charged redox probe led to the highest electroactive surface area, corroborating previous studies of stimulus–response polymers on metal electrodes. Following this material characterization, CHI/Pt brushes were functionalized with aptamers selective for L. monocytogenes capture. These aptasensors were functional at concentrations up to 106 CFU/mL with no preconcentration nor extraneous reagent addition. Selectivity was assessed in the presence of other Gram-positive bacteria (Staphylococcus aureus) and with a food product (chicken broth). Actuation led to improved L. monocytogenes detection with a low limit of detection (33 CFU/10 mL in chicken broth). The aptasensor developed herein offers a simple fabrication procedure with only one-step deposition followed by functionalization and rapid L. monocytogenes detection, with 15 min bacteria capture and 2 min sensing.more » « less
-
Microorganisms are ubiquitous in freshwater aquatic environments, but little is known about their abundance, diversity, and transport. We designed and deployed a remote-operated water-sampling system onboard an unmanned surface vehicle (USV, a remote-controlled boat) to collect and characterize microbes in a freshwater lake in Virginia, USA. The USV collected water samples simultaneously at 5 and 50 cm below the surface of the water at three separate locations over three days in October, 2016. These samples were plated on a non-selective medium (TSA) and on a medium selective for the genusPseudomonas(KBC) to estimate concentrations of culturable bacteria in the lake. Mean concentrations ranged from 134 to 407 CFU/mL for microbes cultured on TSA, and from 2 to 8 CFU/mL for microbes cultured on KBC. There was a significant difference in the concentration of microbes cultured on KBC across three sampling locations in the lake (P= 0.027), suggesting an uneven distribution ofPseudomonasacross the locations sampled. There was also a significant difference in concentrations of microbes cultured on TSA across the three sampling days (P= 0.038), demonstrating daily fluctuations in concentrations of culturable bacteria. There was no significant difference in concentrations of microbes cultured on TSA (P= 0.707) and KBC (P= 0.641) across the two depths sampled, suggesting microorganisms were well-mixed between 5 and 50 cm below the surface of the water. About 1 percent (7/720) of the colonies recovered across all four sampling missions were ice nucleation active (ice+) at temperatures warmer than −10 °C. Our work extends traditional manned observations of aquatic environments to unmanned systems, and highlights the potential for USVs to understand the distribution and diversity of microbes within and above freshwater aquatic environments.more » « less
