Water Quality Testing Research Articles

Ictiofauna y calidad del agua en el sitio ecoturístico “El Remate” Campeche, Mexico: muestreo prospectivo antes del Tren Maya

A prospective punctual sampling was carried out during the rainy season where the quality of the water (nutrients such as: nitrites, sulfates, phosphates and ammonium) and the fish community (ichthyofauna) were measured by means of UVC methodology (underwater visual census), in the ecotourism site “El Remate” which is located in the municipality of Calkiní, Campeche, where an increase in tourism is expected from the “Mayan Train” megaproject. Water quality tests did not reflect a significant anthropic impact on the water body and the ichthyofauna presented ecological characteristics similar to those reported by Torres-Castro et al. (2009), although the number of reported species decreased. The results of this study are proposed as ecological references to continue monitoring this ecosystem and thus address the uncertainty about the impact of the increase in tourist influx on ecosystems of this type. Keywords: UVC methodology, water quality, anthropic impact, Campeche.

Asymptomatic bacteriuria screening for developing countries using a modified water quality test kit.

Between 2% and 15% of pregnant women unknowingly experience asymptomatic bacteriuria (ASB), defined as ≥105 CFU per milliliter of urine in the absence of symptoms. ASB increases the risk of adverse pregnancy outcomes including pyelonephritis, preterm labor, and low-birth weight infants. While pregnant women in the United States are routinely screened for ASB, those in developing countries with limited resources and funding lack an accurate mechanism for ASB screening. Aquagenx water quality test kits detect Escherichia coli, the most common causative agent of ASB, and total coliform bacteria in drinking water via colorimetric and fluorescent indicators. We found that the Aquagenx system is compatible with human urine and then proceeded to develop an ASB screening protocol using disposable inoculating loops. Our protocol diagnosed artificial ASB- samples (104 CFU/mL E. coli) with a false positive (FP) rate of 33% (n = 18) and ASB+ (105 CFU/mL E. coli) with a false negative (FN) rate of 5.6% (n = 18). Clinical sample testing with our protocol revealed a FP rate of 0% in ASB- samples (n = 28) and a FN rate of 0% in ASB+ samples caused by coliforms (n = 13). Aquagenx did not detect ASB in nine clinical samples with non-coliform etiological agents due to the limitations of the technology. However, with very high accuracy for detection of E. coli and other causative agents that collectively account for 90.1% of ASB cases, these kits could be used as a diagnostic ASB screening tool in developing countries in which there is currently no alternative to urine culture.IMPORTANCEAsymptomatic bacteriuria (ASB) affects 2%-15% of pregnant women and can result in adverse maternal and fetal outcomes if left undetected and untreated. In the United States and other developed nations, pregnant women are regularly screened for ASB via urine culture. However, in low-resource countries where bacterial culture is not available, dipstick testing is used. Although accurate in cases of symptomatic bacteriuria, dipstick detection is ineffective for detecting ASB. Here, we made use of an existing water quality field test for ASB urine screening, which would be readily deployable in low-resource settings. We optimized a dilution protocol for sampling patient urine within the detection limits of the Aquagenx kit technology. Overall, we were able to detect ASB samples with Gram-negative pathogens that collectively account for 90% of all ASB cases. Utilization of this repurposed technology for proactive medical screening may help prevent adverse pregnancy and birth outcomes due to ASB.

Analisis Kualitas dan Indeks Pencemaran Air pada Usaha Budidaya Perikanan di Desa Kota Karang Kecamatan Kumpeh Ulu Kabupaten Muaro Jambi

This research aims to analyze the quality of freshwater cultivation and analyze the pollution index for freshwater cultivation in Desa Kota Karang, Kec. Kumpeh Ulu, Kabupaten Muaro Jambi. This research uses quantitative analysis techniques. The results of analysis and water quality tests concluded that the cultivation ponds in Desa Kota Karang were in the lightly polluted category. Based on research conducted on 10 ponds, there were 3 ponds that met quality standards, the rest were in the lightly polluted category. This is based on tests and analysis of physical, chemical and biological parameters. Meanwhile, the results of the pollution index analysis obtained IP values ranging from 0.88 to 2.91. According to PP Number 22 of 2021, if 1 < IP ≤ 5 then the cultivation pond in Desa Kota Karang is in the lightly polluted category. Based on the results of the air quality analysis and pollution index, the air quality in the cultivation ponds in Kota Karang Village is still suitable for use for fish cultivation. Therefore, it is necessary to carry out further monitoring and recovery efforts for BOD and COD parameters that have exceeded class III quality standards of PP Number 22 of 2021 concerning Freshwater Fisheries Cultivation, so that ponds in Desa Kota Karang remain safe for carrying out cultivation activities.

Fluorescence switching sensor for sensitive detection of curcumin/Mn2+ using biomass carbon quantum dots: A combination of experimental and theoretical insights

Compared to high-performance liquid chromatography, capillary electrophoresis, and electrochemical analysis, fluorescent carbon quantum dots (CQDs)derived from biomass materials have garnered significant attention due to their non-toxic, eco-friendly, and renewable advantages. In this research, CQDs-NH2 was synthesized in one step by hydrothermal method using banana peel as biomass carbon source and ethylenediamine (EDA) as dopant. The blue fluorescence of CQDs-NH2 was found to be quenched by the addition of curcumin through the synergistic effect of static quenching and internal filtering effect (IFE). The response to curcumin showed good linearity in the concentration range of 1–15 μM with a limit of detection (LOD) of 18.56 nM. The fluorescence of CQDs-NH2 was partially restored in the presence of curcumin and Mn2+, leading to the establishment of a curcumin@CQDs-NH2 switch sensor for the detection of Mn2+ in the linear range of 5–60 μM with a LOD of 20.35 nM. Furthermore, density functional theory (DFT) calculations suggest that the interaction between Mn2+ and curcumin is stronger than the interaction between Mn2+ and functionalized CQDs (f-CQDs), elucidating the introduction of Mn2+ disrupts the interaction between curcumin and CQDs-NH2, leading to the restoration of CQDs-NH2 fluorescence. Finally, the CQDs-NH2 fluorescence switch sensor demonstrated high accuracy and precision in liquid food and water quality testing with recoveries ranging from 95.19 % to 105.54 %.

THE EFFECT OF GIVING NATURAL FEED FROM CULTURES OF ROTIFERS (Brachionus sp.) TO GROWRTH OF WHITE SEAPER (Lates calcarifer) LARVA AND WATER QUALITY AT PT. BALI BARRAMUNDI, BULELENG DISTRICT, BALI

This research was to determine the effect of providing natural food cultures of phytoplankton and rotifers in white snapper (Lates calcarifer) hatcheries on air quality at PT. Bali Barramundi Buleleng Regency, Bali. The rotifer culture will be successful in harvesting if there is sufficient food for the rotifer zooplankton (Brachionus sp.). One good food for rotifer growth is Chlorella sp. To get 500-700 rotifers/ml for 3 weeks with an initial inoculation of 10 birds/ml requires 5 million Chlorella sp cells/ml. The air used for rotifer zooplankton is sea air which is taken directly through 3 pumps connected to pipes installed in the sea at a distance of approximately 100 meters from the shoreline. The air that has been collected is added with chlorine at a dose of 25 ppm, then after stirring thoroughly, turn off the aeration in the tub. After 1x24 hours, add sodium thiosulfate at a dose of 0.125 ppm and turn on the aeration after a while. Before being given to larvae, rotifers and enriched first using Algamax, vitamin C at a dose of 2.5g/10 L for one hour. Rotifers are given with an initial density of 4-5 ind/ml (4,000-5,000 individuals/1,000L). Natural rotifer food is given twice a day for larvae (D2-D5) at 09.00 and 15.00 and given four times a day for larvae (D6-D25) at 08.00, 10.00, 14.00, 16.00 with a dose of (5-10 tail/ml). The results of spawning showed an average hatching degree (HR) of 65% - 90.5% and normal growth up to D25 with a length of 9.5 mm. The water quality test results obtained were temperatures ranging from (28 – 30)⁰ C, pH (7.5 – 8.5), DO (6.5-6.54) ppm, salinity (28 – 36) ppt, nitrate (2.6 – 3.2) ppm, phosphate 0.01 ppm and ammonia (0.05-0.06) ppm.

Bimetallic complexation for significant fluorescence enhancement of faecal pigment towards water quality testing

Systematic spectroscopic investigations revealed bimetallic complexation of faecal pigments (FP) in waterthrough their multiple binding sites. FP-Zn(II)/Gd(III) complexes showed narrow emission (FWHM ∼ 26 nm) with maximum intensity compared to different bimetallic complexes in water. The fluorescence intensity of bimetallic Zn(II)/Gd(III) complexes of FP increased ∼3–5 fold in aqueous media compared to the FP-Zn(II) complexes, i.e. well-known as Schlesinger’s test. The optimum Zn(II): Gd(III) stoichiometry was observed at 3:2 for maximum FP fluorescence enhancement. The bimetallic FP-Zn(II)/Gd(III) complexes also exhibited higher fluorescence lifetimes and quantum yield than FP-Zn(II) complexes. The photophysical investigations demonstrated that bimetallic Zn(II)/Gd(III) complexation increased the rigidity of chromophores present in FP. Consequently, a decrease in non-radiative decay rate constants (knr) by ∼ 1.5 times was observed for bimetallic complexes compared to FP-Zn(II) in water. Hence, a detection limit of the nanomolar concentration range of FP could be achieved in the aqueous media. The effect of diverse interfering factors (humic acid, water hardness, pH) on the fluorescence behaviour of FP-Zn(II)/Gd(III) complexes was also investigated with an approach mimicking real water samples. Finally, a simple non-extraction analytical approach for sensitive detection of FP in water was demonstrated while also considering the fluorescence matrix interference problem.

Assessing biosocial vectors in water contamination, the incidence of water-borne illnesses, and insecurity in Kathmandu, Nepal

ABSTRACT In this study, we use water quality tests, epidemiological data, and ethnographic interviews gathered in Kathmandu in 2017 to provide an interdisciplinary analysis of water insecurity, illness, and targeted responses. Our findings fit the pattern of the past 20 years: the concentration of coliform bacteria across water sources remains unsafe. Our epidemiological data documents high rates of water-borne infectious diseases consistent with fecal contamination of water sources. Our ethnographic interviews suggest that social marginalization, poverty, and dislocation are major drivers in the incidence of illness. Evaluating some of the collective responses to water insecurity and contamination, we argue that effectively addressing water pollution, scarcity, and health outcomes in Kathmandu requires redirecting the focus of programs and the primary methods of implementation. Instead of large-scale top-down infrastructural interventions such as the Melamchi Water Supply Project, programs should target women's leadership in and subsidize funding for small-scale, community-managed interventions.

Groundwater and indoor air quality of urban village housing: study in Janturan, Warungboto, Yogyakarta

Water and air are important elements for life. The presence of pathogenic bacteria in the surrounding environment can cause health problems resulting from the low quality of water and air. The purpose of this study is to measure the quality of groundwater and air based on microbiological parameters in urban village housing. This research was conducted in a descriptive survey, and a purposive sampling technique was carried out. Groundwater and air samples were taken from six residents' houses located in the Janturan area. The water quality test used the most probable number (MPN) method and the air quality test used the agar filter method using a microbiological air sampler (MAS) to trap microbes. The results of the MPN test for total coliform bacteria from six samples of groundwater showed that three samples were positive for coliform bacteria which exceeded the threshold according to Indonesian standard<50 MPN/100 ml. Assay of <em>E. coli</em> bacteria showed that all samples of groundwater positively contained <em>E. coli</em> bacteria which exceeded the threshold of 0 MPN/100 ml. The results of indoor air quality measurements from 6 residents' houses showed that five houses have air quality did not meet the standard for indoor air germ numbers based on Indonesian standard, less than 700 CFU/m3 (colony forming units per metres cubic) and 1 house that got the number of airborne germs, in the normal range, namely 356 CFU/m3. It was concluded that the water quality and air quality in the urban village did not meet health requirements.

Diagnostic screening of private well water using gas chromatography with high resolution mass spectrometry to support well water management

In the US, private well users are responsible for their own water quality testing, but local health officials are often uncertain what tests to recommend, particularly for regulated organic chemical contaminants. This study evaluated the utility of suspect and non-target screening (NTS) high resolution mass spectrometry (HRMS) as a tool to identify a wide range of organic chemicals of emerging concern in private well water and to inform well water management decisions. Qualitative NTS, which detects chemicals without providing concentrations, was used to analyze 25 private well water samples from Wake County, North Carolina. Using the NIST 20 mass spectral database (M1), NTS tentatively identified 106 unique organic chemicals across the 25 samples and an average of 11 organic chemicals per sample. At least one USEPA ToxCast chemical was identified in each private well water sample. Private well water users were interviewed prior to and after their sample's NTS results were reported back; four county groundwater managers were interviewed after aggregated results for all 25 water samples were reported back. All but one well user participant chose to participate in the reporting-back post-interview. The 24 private well users found NTS results useful and valued the contextualization of their results using NTS results for other well users and a local municipal water sample. Most private well users (67%) were surprised by their well water results, especially regarding the number of tentatively identified organic chemicals detected. All the groundwater managers believed the NTS results were useful and could help improve their testing recommendations to private well users. Even with qualitative limitations, NTS results can be an effective and valuable tool to inform the public and governance stakeholders in decisions around groundwater quality management.

Revealing Conditions of Detailed Water Usage, Daily Life Water Quality, and Awareness Related to Waste Water at Urban Kampung in Indonesia

This research aimed to investigate the actual water use of residents and the quality of well water used daily at the urban kampung located in Bandung, Indonesia. The status of wastewater treatment and residents' awareness of the water environment were also investigated in the target area. The methodology used included a survey of residents, water quality testing, and an assessment of wastewater practices. The results showed that approximately one-half of the respondents used water from the water utility, with the other half using well water as their main domestic water source. Identifying water sources by end-use revealed that residents mainly used bottled water for drinking and cooking. Since Escherichia coli was detected in many wells, it is not recommended that residents drink well water without disinfection. In addition, most of the wastewater in the area was discharged into a nearby river without treatment.

PELAKSANAAN PENGAWASAN TERHADAP DEPOT AIR MINUM ISI ULANG DI RW 02 DAN RW 09 KELURAHAN KRAMAT PELA, JAKARTA SELATAN

Refillable drinking water depots (DAMIU) offer a practical solution for the community's drinking water needs. However, the condition of DAMIUs that produce drinking water for the community needs to be supervised in accordance with applicable regulations as a form of consumer protection. This study aims to examine the implementation of DAM supervision in RW 02 and RW 09 Kramat Pela Urban Village, South Jakarta, as well as the application of sanctions for DAM business actors who do not comply with standards. The research is conducted socio-legally from regulations and related literature. The analysis is carried out qualitatively with an inductive method. The results of the analysis show that there are DAMs that do not meet the standards, as evidenced by the presence of E.Coli and Coliform bacteria in refill drinking water and violations in the water treatment and distribution process. Lack of supervision by the Puskesmas and related agencies through water quality testing and periodic inspections in accordance with the Minister of Health Regulation No. 2 Year 2023 on the Implementation of Government Regulation No. 66 Year 2014 on Environmental Health is the main problem. The sanction given by the Puskesmas is only a verbal warning, but there is no further evaluation after the sanction is given.

Interpretation of subsurface layers using the Wenner configuration geoelectric method and geochemical tests: Case study at Muara Fajar landfill – Rumbai, Pekanbaru

The need for water daily is a big problem for people living around Muara Fajar landfill – Rumbai, Pekanbaru. This study aims to identify the depth of subsurface structures around the Muara Fajar landfill area using the Wenner configuration dielectric method and determine the water quality in the community wells around the landfill site. The data obtained in the acquisition process are used to calculate the apparent resistivity value at each measurement point and analyzed quantitatively and qualitatively. Then proceed with the inversion process using the progress program so that obtained resistivity value and layer thickness at each point of measurement. The results of measurement in track-1 get a range of resistivity values ranging from 62.9 – 171 ohm-meters and track-2 from 32.4 – 70.6 ohm-meters. Underground water taken is residents' well water in the research area as many as 5 sample points using GPS. This underground water sample will be tested with parameters such as pH, TDS, BOD, COD, NH3, and turbidity. Underground water cannot be consumed from the results of the water quality test with the parameters mentioned at the beginning if referring to the Regulation of the Minister of Health of the Republic of Indonesia because the pH obtained in all underground water samples is < 6.5 or acidic, the value of the BOD, COD, NH3, and turbidity parameters, the values are by the quality standard.

Durable Multilayered Sleeve-Structured Hybrid Nanogenerator for Efficient Water Wave Energy Harvesting.

The state-of-the-art triboelectric nanogenerator (TENG) technology has numerous advantages and creates new prospects for the rapid development of the Internet of Things (IoT) in marine environments. Here, to accelerate the application process of TENG, an elaborately designed multilayered sleeve-structured hybrid nanogenerator (M-HNG) is developed to efficiently and persistently harvest marine energy. The M-HNG integrates an electromagnetic nanogenerator (EMG) with four coils and a multilayered sleeve-structured TENG (MS-TENG) with three freestanding layer units to increase spatial utilization efficiency. Moreover, rabbit fur strips are introduced to enhance the output performance and strengthen the durability of TENG. Therefore, the MS-TENG has high durability due to its soft-contact structure, maintaining its performance even after 240,000 cycles. When a 1000 μF capacitor is charged by M-HNG utilizing a power management circuit (PMC), the stored energy is increased from 2.62 mJ to 140.11 mJ, representing a significant improvement of 52-fold. The M-HNG triggered by water waves has successfully powered various small electronic devices, including 1200 LED lights, nine thermo-hygrometers, a water quality testing pen, and water level alarms. The proposed M-HNG effectively harvests low-frequency water wave energy, introducing an innovative concept for constructing a hybrid TENG with enhanced density and durability.

Development of Ecotourism Scenario Based on Seawater Quality Evaluation

There were various activities in the Bungkutoko Island Kali Biru Bathing area by PT. Pelindo Nusantara and community settlements can unwittingly impact the quality of the water environment. This study aimed to determine the quality of seawater in the Kali Biru bathing area and develop a sustainable tourism-based environmental engineering concept. This research method uses surveys and laboratory analysis. Examination of water samples is carried out directly. Seawater analysis is descriptive with quality data from the results of water quality tests in testing laboratories whose feasibility levels were determined based on Indonesia's government rule number 22 of 2012. The results showed that three elements had laboratory test values exceeding the threshold value, namely: nitrite (NO2-N), sulfate (SO4), and iron (Fe), which should not be present, but during the study, there were already values for nitrite (NO2-N) of 0.12, 0.006, and 0.0006, sulfate (SO4) of 2.3, 1.4, and 4.8 and iron (Fe) of 0.0012, 0.0019, and 0.001 while the other six elements starting from pH (degree of acidity), salinity (%), nitrate (NO3-N), oil and grease, arsenic (As), and total coliform were within the regional quality threshold sea tourism. Scenarios for developing tourism activities through ecotourism activities.

Improving Private Well Testing Programs: Experimental Evidence from Iowa.

Approximately 23 million U.S. households rely on private wells for drinking water. This study first summarizes drinking water behaviors and perceptions from a large-scale survey of households that rely on private wells in Iowa. Few households test as frequently as recommended by public health experts. Around 40% of households do not regularly test, treat, or avoid their drinking water, suggesting pollution exposure may be widespread among this population. Next, we utilize a randomized control trial to study how nitrate test strips and information about a free, comprehensive water quality testing program influence households' behaviors and perceptions. The intervention significantly increased testing, including high-quality follow-up testing, but had limited statistically detectable impacts on other behaviors and perceptions. Households' willingness to pay for nitrate test kits and testing information exceeds program costs, suggesting that the intervention was welfare-enhancing.

Seasonal Effects of Constructed Wetlands on Water Quality Characteristics in Jinshan Lake: A Gate Dam Lake (Zhenjiang City, China).

Urban lakes commonly suffer from nutrient over-enrichment, resulting in water quality deterioration and eutrophication. Constructed wetlands are widely employed for ecological restoration in such lakes but their efficacy in water purification noticeably fluctuates with the seasons. This study takes the constructed wetland of Jinshan Lake as an example. By analyzing the water quality parameters at three depths during both summer and winter, this study explores the influence of the constructed wetland on the water quality of each layer during different seasons and elucidates the potential mechanisms underlying these seasonal effects. The results indicate that the constructed wetland significantly enhances total nitrogen (TN) concentration during summer and exhibits the capacity for nitrate-nitrogen removal in winter. However, its efficacy in removing total phosphorus (TP) is limited, and may even serve as a potential phosphorus (P) source for the lake during winter. Water quality test results of different samples indicated they belong to Class III or IV. Restrictive factors varied across seasons: nitrate-nitrogen and BOD5 jointly affected water quality in winter, whereas TP predominantly constrained water quality in summer. These results could provide a reference for water quality monitoring and management strategies of constructed wetlands in different seasons in Jiangsu Province.

Teknik Pembenihan Ikan Kerapu Cantang (Ephinephelus sp.) di Balai Budidaya Air Payau, Situbondo, Jawa Timur

Grouper fish (Epinephelus sp.) is one of the popular marine fish species in the market in Indonesia and abroad in Southeast Asia, this fish has high economic value, good taste. Currently, the development of grouper aquaculture has been growing, so the seeds must be available continuously to meet the demand for seeds, therefore the foundation of interspecies crosses between groupers that have a high heterosis effect in growth traits, disease resistance and environmental resistance. This research activity was carried out at the Brackish Water Aquaculture Center located in Situbondo, East Java and was carried out from June 19, 2023 to August 19, 2023. The working method used in the Field Work Practice is descriptive method with data collection including primary and secondary. The technique of grouper hatchery conducted at the Brackish Water Aquaculture Fisheries Center stages include tub preparation, broodstock rearing, hybridization, hatching and egg stocking, larval development, feeding, water quality management, growth sampling and grading, pests and diseases, and harvesting and marketing. The results of the observed parameters are HR 73.25%, SR 15.98%, FR 74.16%. Water quality management carried out in grouper hatcheries is water reduction and water changes according to larval age, siphon once a week and water quality tests.

Diversity of Fish Species as Bioindicators of Water Quality in The Cikapundung River, Bandung City

Human activity along the river impacts the aquatic environment from biotic and abiotic factors. One indicator that can reflect the quality of the waters is fish diversity. Several studies have used fish diversity as a biological indicator to determine the quality of waters, such as lake and river waters. The purpose of this study was to determine the diversity of fish and also to determine the quality of water in the Cikapundung River, Bandung City. The method used in this study was a survey and exploration method, which involved collecting samples at five stations using umbrella traps, cast nets, and fishing gear in the morning and evening. The fish obtained were identified using the Fish Identification Guidebook, and the number of each type was calculated. The biotic data obtained were processed using the Shannon-Weiner diversity index (H'), Evenness index (E), Margalef Abundance index (Dmg), and Simpson Dominance index (C). In contrast, the abiotic data were sent to the water quality testing institution (LPKL). The study's results identified seven species from 5 families: Cyprinus sp., Ancistrus sp., Xiphophorus sp., Barbodes sp. According to the Shannon-Weiner index, the diversity of fish species in the Cikapundung River in Bandung City is relatively moderate, with a value (H') of 1.55. The results of water quality measurements of the Cikapundung River from LPKL based on the class II water quality standards of PP RI Number 22 of 2021 show that the condition of the river is in the moderately polluted category.

Risk-based critical concentrations of enteric pathogens for recreational water criteria and recommended minimum sample volumes for routine water monitoring

Concerns are rising about the contamination of recreational waters from human and animal waste, along with associated risks to public health. However, existing guidelines for managing pathogens in these environments have not yet fully integrated risk-based pathogen-specific criteria, which, along with recent advancements in indicators and markers, are essential to improve the protection of public health. This study aimed to establish risk-based critical concentration benchmarks for significant enteric pathogens, i.e., norovirus, rotavirus, adenovirus, Cryptosporidium spp., Giardia lamblia, Campylobacter jejuni, Salmonella spp., and Escherichia coli O157:H7. Applying a 0.036 risk benchmark to both marine and freshwater environments, the study identified the lowest critical concentrations for children, who are the most susceptible group. Norovirus, C. jejuni, and Cryptosporidium presented lowest median critical concentrations for virus, bacteria, and protozoa, respectively: 0.74 GC, 1.73 CFU, and 0.39 viable oocysts per 100 mL in freshwater for children. These values were then used to determine minimum sample volumes corresponding to different recovery rates for culture method, digital polymerase chain reaction and quantitative PCR methods. The results indicate that for children, norovirus required the largest sample volumes of freshwater and marine water (52.08 to 178.57 L, based on the 5th percentile with a 10 % recovery rate), reflecting its low critical concentration and high potential for causing illness. In contrast, adenovirus and rotavirus required significantly smaller volumes (approximately 0.24 to 1.33 L). C. jejuni and Cryptosporidium, which required the highest sampling volumes for bacteria and protozoa, needed 1.72 to 11.09 L and 4.17 to 25.51 L, respectively. Additionally, the presented risk-based framework could provide a model for establishing pathogen thresholds, potentially guiding the creation of extensive risk-based criteria for various pathogens in recreational waters, thus aiding public health authorities in decision-making, strengthening pathogen monitoring, and improving water quality testing accuracy for enhanced health protection.

Water Quality of Unconfined Aquifer in Universitas Negeri Malang Following the Drinking Water Quality Standard of Indonesian Ministry of Health

The quality of groundwater is naturally determined by water-bearing rock characteristics. However, the progression of civilian activities also negatively affects the groundwater quality. Therefore, this study aims to assess the physical, chemical, and biological characteristics of groundwater in the Universitas Negeri Malang (UM) campus area in Indonesia and evaluate its compliance with drinking water quality standards, particularly the Class A standard. A comparative descriptive strategy was utilized in the study by involving groundwater in the campus area of UM. The focus of the research is water quality in unconfined aquifer. Through purposive sampling, 12 wells were selected to ensure appropriate spatial dispersion. Water samples were collected in sample bottles and tested for physical, biological, and chemical properties. These water quality tests were carried out in the Perum Jasa Tirta I Malang. Water quality data were analyzed qualitatively, descriptively, and comparatively. This study concludes that (1) the groundwater on the UM campus generally meets the physical criteria for drinking water quality standards; (2) the chemical quality of the groundwater on the UM campus still satisfies the drinking water quality standards; and (3) biologically, the free groundwater on the UM campus fails to meet drinking water quality standards. The novelty of this research is that the biggest threat to the quality of free groundwater in the campus area is bacterial contamination from sanitation activities. Accordingly, it is recommended that groundwater is boiled before being utilized for drinking water purposes to neutralize the E. coli bacteria present in all well water samples.Keywords: Water Quality; Unconfined Aquifer; The Drinking Water; Quality Standard