Assessment of bacteriological quality and physico-chemical parameters of domestic water sources in Samaru community, Zaria, Northwest Nigeria

Evaluation of groundwater quality and potential health risks in the Tengratila Gas Field Blowout Region, Bangladesh: An in-depth analysis utilizing multivariate statistics, heavy metal indices and Monte Carlo simulation

Safe drinking water assessment is crucial for municipal and national health and socioeconomic issues. This study focuses on drinking water quality and health risks around the Tengratila gas field, which experienced two blowouts within six months in 2005. In total, 27 groundwater samples were collected for evaluating several physicochemical parameters and heavy metal concentrations. The concentrations of lead, cadmium, manganese, and arsenic were found at elevated amounts surpassing the international standards. Single Factor and Nemerow Pollution Indices, Heavy Metal Pollution Index (HMPI), and Heavy Metal Evaluation Index (HMEI) were used to assess contamination level. Overall, 89 % of HMPIs and 100 % of HMEIs stated excessive heavy metal contamination. Two demographic groups were considered for health risk using deterministic and Monte Carlo probabilistic approaches to confront uncertainty. These analyses concluded children had higher non-carcinogenic and carcinogenic health risks than adults. Multivariate techniques including correlation coefficients, CA, ANOVA and Tukey test were performed to comprehend water quality parameters connections and variability. PCA and PMF identified three distinct groups demonstrating how geological, geomorphic and anthropogenic factor affect water quality. Therefore, this article accumulates an extensive analysis of drinking water quality along with its environmental impact, which is undoubtedly vital for such densely populated habitat.

Comprehensive analysis and human health risk assessment of tap water quality in Dhaka City, Bangladesh: Integrating source identification, index-based evaluation, and heavy metal assessment

Despite potential contamination, tap water remains the primary source of drinking in megacities. However, the sources of heavy metal(oid)s contamination and associated health hazards have not been thoroughly addressed in many developing cities, including Dhaka. Therefore, we made the first attempt to assess tap water quality in Dhaka City using indices, identify pollution sources with state-of-the-art techniques, and quantify associated health risks. Tap water samples from 35 locations were collected and analyzed for physicochemical properties and heavy metal(loid)s concentrations. While most parameters were within acceptable ranges, Hg (1.18 ± 0.15 µg/L) exceeded safety thresholds with concerns for Mn (51.08 ± 2.3 µg/L) and Fe (177.34 ± 5.6 µg/L). The calculated indices indicated that Dhaka City's tap water ranged from unfit (Heavy Metal Evaluation Index, HEI: 2.61), very poor (Heavy Metal Pollution Index, HPI: 95.67, Water Quality Index, WQI: 37.76), moderately affected (Metal Index, MI: 2.61, Synthetic Pollution Index, SPI: 0.96) to slightly polluted (Single-factor Index, Pij: 2.61, Nemerow Pollution Index, NPI: 1.41), healthy but not tasty (Taste Index, TI: 1.8, Health Index, HtI: 10.41), with Matuail, followed by Jurain, being the most contaminated. Non-carcinogenic health risk (NCR) values revealed that children were twice as susceptible to health risks from Pb, Co, and As. Alongside, Carcinogenic health hazards risk (CR) expressed potential cancer risks from Cr Collapse

Key Words

• Contamination
• DWASA
• Illegal industrial discharge
• Threshold
• Toxicity

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MESH Headings

• Bangladesh
• Metals, Heavy/analysis
• Metals, Heavy/toxicity
• Risk Assessment
• Humans
• Water Pollutants, Chemical/analysis
• Water Pollutants, Chemical/toxicity
• Drinking Water/analysis
• Water Quality
• Environmental Monitoring
• Cities
• Water Supply

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Grants Collapse

Affiliation(s)

Tasrif Nur Ariyan Department of Environmental Science, Bangladesh University of Professionals, Mirpur Cantonment, Dhaka 1216, Bangladesh
Shamshad Begum Quraishi Planning and Development Division, Bangladesh Atomic Energy Commission (BAEC), Dhaka 1207, Bangladesh
Md Nur E Alam Atomic Energy Centre (AEC), Shahbagh, Dhaka 1000, Bangladesh
Muhammad Shahidur Rahman Khan Atomic Energy Centre (AEC), Shahbagh, Dhaka 1000, Bangladesh
Farzana Ferdous Faria Department of Environmental Science, Bangladesh University of Professionals, Mirpur Cantonment, Dhaka 1216, Bangladesh
Alamgir Kabir Department of Environmental Science, Bangladesh University of Professionals, Mirpur Cantonment, Dhaka 1216, Bangladesh.

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Water quality assessment of river Ganga, India using water quality index and multivariate statistical techniques

The River Ganga is a vital lifeline for millions, and several authors reported that its quality has been deteriorating. Several initiatives have been taken by the government, but the situation is not up to the mark. Hence, water quality assessments are essential for sustainable river water management and restoring its ecological balance. This work employed spatiotemporal analysis of 20 hydrochemical variables, water quality indices (WQI), and multivariate statistics to assess the water quality of River Ganga. Water samples (n = 220) were collected at 20 locations (divided into four zones, namely upper (UZ), middle (MZ), lower (LZ), and estuarine (EZ)) based on the geographical nature and anthropogenic pressure. The study found that most of the water variables (specific conductivity (SC), pH, BOD, total alkalinity (TA), total hardness (TH), Ca-H, Mg-H, chlorinity (Cl-), salinity, nitrate-N, silicate and total dissolved solids (TDS)) were lowest reported at UZ while the highest at EZ. TH, salinity, Mg-H, Ca-H, TDS, Cl-, and SC in EZ, were above the drinking water limits and these variables markedly affect the river's water quality attributes, possibly increased by tidal influences. WQI indicated that the UZ was clean (26-50) in all seasons, MZ and LZ were good to poor (50-75) in all seasons, and EZ was unsuitable for drinking (> 100) in all seasons. Seasons were grouped into three clusters: less polluted (monsoon); slightly polluted (post-monsoon); and polluted (winter and pre-monsoon). The principal component analysis formed five clusters based on eigenvalue > 1: PC1 having TH, salinity, Mg-H, Ca-H, TDS, Cl-, and SC mainly influenced by tidal factor; PC2 having temperature, transparency, and DO was influenced by metrological source; PC3 (pH, TA, velocity) and PC4 (BOD, silicate) thought to be both natural as well as manmade; and PC5 was influenced by agricultural runoff (total phosphorus and NO3-N) and sewage water (TN) discharge. The study emphasized the significance of multivariate statistical techniques in discerning the variability patterns of parameters, as well as in formulating management strategies to enhance river water quality by pinpointing the most impactful parameters contributing to water quality degradation.

Biofilm-Forming Antibiotic-Resistant Bacteria in Water From Distribution Systems: Occurrence and Public Health Implications

Biofilm is a structurally-connected microbial community, covered by a self-produced polymeric matrix and adhered to biotic or abiotic surfaces. This study aimed to evaluate the occurrence of biofilm-producing antibiotic-resistant bacteria in water from distribution systems. Water samples were taken from 32 tanks across Ondo City and Akure metropolis, Nigeria. Information regarding the sanitation status of the tanks was gathered by observation and oral interviews. The physicochemical properties were determined using standard methods. Using the pour plate technique. Agars included serially diluted water samples were inoculated onto plate count agar, mannitol salt agar, Salmonella-Shigella agar, MacConkey agar, and cetrimide nutrient agar to assess total viable bacteria, Staphylococcus aureus, Salmonella and Shigella, coliforms, and Pseudomonas aeruginosa, respectively. Eosin-methylene blue agar was used to cultivate Escherichia coli and Enterobacter aerogenes. Pure isolates were characterised using API kits and assessed for antibiotic resistance and biofilm production employing the Kirby-Bauer and tissue culture plate techniques, respectively. The ages of the water tanks ranged from 1 to 25 years old; all tanks had cover-lids; 13 (40.63%) had water guards while 12 (37.5%) underwent water treatment. The physicochemical properties chiefly fell within WHO standards for drinking water. One hundred and eighty-seven isolates were obtained. S. aureus (15.51%) had the highest frequency while Salmonella enterica (3.2%) had the lowest frequency. Thirty-six percent of the isolates were strong biofilm producers, while 20.67% Gram-negative and 18.69% Gram-positive bacterial isolates were antibiotic-resistant. This study revealed a high occurrence of biofilm-forming bacteria and prevalence of antibiotic-resistant bacteria in water distribution systems, emphasizing the urgency of improving water quality for public health protection.

Systematic review and meta-analyses of the role of drinking water sources in the environmental dissemination of antibiotic-resistant Escherichia coli in Africa

Escherichia coli are pathogenic and antibiotic-resistant organisms that can spread to humans through water. However, there is sparse synthesised information on the dissemination of antibiotic-resistant E. coli through drinking water in Africa. This review provides an overview of the environmental spread of antimicrobial-resistant E. coli through drinking water in Africa. We performed a systematic review based on PRISMA guidelines, and 40 eligible studies from 12 countries were identified until June 2023. Four electronic databases (PubMed, Elsevier, AJOL, and DOAJ) were searched. Studies that employed phenotypic tests (n = 24/40) in identifying the bacterium outstripped those that utilised genome-based methods (n = 13). Of the 40 studies, nine and five, respectively, assessed the bacterium for antimicrobial resistance (AMR) phenotype and genotype. Multiple antibiotic resistance indices of 0.04-0.1 revealed a low level of antibiotic resistance. The detection of multidrug-resistant E. coli carrying resistance genes in certain water sources suggests that AMR-surveillance expansion should include drinking water.

Statistical and geospatial assessment of trace and toxic elements distribution in ground and surface water of northern parts of the Indo-Gangetic plains: Source identification and health risk assessment

This study focusses on ground and surface water resources in the northern parts of the Indo-Gangetic Plains. The study aims to identify potential contaminants, analyse their distribution, trace their origins, and evaluate associated health risk. Samples from 80 locations; groundwater (n = 69) and surface water (n = 11) were analysed for nineteen trace and toxic elements using ICP-MS. Eight elements in groundwater (Mn, Fe, Ni, Zn, As, Tl, U and Se) and six in surface water (Al, Mn, Fe, Ni, Zn, and Tl) exceeded WHO (2011) and BIS (2012) limits in certain areas. The geospatial analysis reveals hotspots of trace and toxic element concentration, with higher levels detected in the southeast and western regions of the study area. Correlation matrices revealed a robust correlation (∼>0.75-0.99, p < 0.01) among all trace and toxic elements (excluding Li, Be, As, Ag, and U) in surface water samples when compared to groundwater samples. Cluster analysis and principal component analysis (PCA) (explains 70.09 cumulative percent for total 6 of factors) of groundwater chemistry indicates that Zn, Ni and Tl contamination may originate from industrial activities (metallurgical processes and manufacturing). The potential sources of Mn may be both geological and human-induced, while Fe, Se, As and U can originate from specific geological formations or human-related activities like over-extraction and leaching of excess fertilizers into aquifers. For surface water, PCA (explains 92.92 cumulative percent for total 5 of factors) identifies industrial activities as the main source of Mn, Fe, Tl, Ni, and Zn, while Al originates from both geological and anthropogenic sources. The water quality index indicated poor to very poor water quality in the western and central regions, whereas the northern and eastern regions exhibited excellent water quality. Health risk assessment reveals HI values for groundwater water: 3.85 (adults), 7.70 (children); surface water: 1.52 (adults), 3.05 (children), emphasizing the urgent need for remediation measures.

Comparative ecotoxicological study on the current status of artisanal crude oil contaminated mangrove swamps in Rivers State, Southern Nigeria

The rise in illegal crude oil theft and refining in the southern Niger Delta region of Nigeria, especially in Rivers State, has led to significant environmental damage to aquatic ecosystems. A study was carried out to assess the impact of crude oil bunkering on aquatic environments and fish samples from Oproama, Sama-Naguakiri, and Abalama over six months. Findings revealed that Oproama had the highest levels of biological oxygen demand (3.60 ± 0.79 mg/L), electrical conductivity (34.07 ± 3.62 μS/cm), total dissolved solids (28.17 ± 3.77 mg/L), and temperature (29.50 ± 0.74 °C). In contrast, Sama-Naguakiri recorded the highest pH (6.72 ± 0.14) and dissolved oxygen (3.35 ± 0.11 mg/L). Though minor variances were noted between Sama-Naguakiri and Abalama, a significant difference (P < 0.05) was observed between these areas and Oproama. Importantly, all measured values adhered to WHO/FAO standards. Analysis of potentially harmful metals in sediment and water indicated notable distinctions among the three sites, with Sama-Naguakiri exhibiting the highest levels of Zn (114.5 ± 1.5 mg/kg), Cu (237.8 ± 0.9 mg/kg), Pb (3.6 ± 1.2 mg/kg), and Cd (1.1 ± 0.4 mg/kg). Conversely, Abalama showed the lowest zinc (105.2 ± 1.5 mg/kg) and lead (2.4 ± 0.5 mg/kg) concentrations, while Oproama displayed the lowest copper level (0.8 ± 0.3 mg/kg). The concentrations of heavy metals in the water, sediment, and fish surpassed the permissible limits established by NESREA, the EPA, and WHO, except for arsenic. The presence of heavy metals in this region could pose significant ecological and health hazards, underscoring the urgency for immediate remedial measures to safeguard the environment and this fish-dependent community.

Assessing microbiological and heavy metal pollution in surface waters associated with potential human health risk assessment at fish ingestion exposure

Fish represent a significant source of nutrients but also cause negative health effects due to their bioaccumulation capacity for pollutants. The aim of this study was to examine the transfer of metals from the water of several rivers (Somes, Tisa, Sasar, Lapus, Lăpusel) to fish (Caras sp) tissue (subcutaneous fat, muscles, liver, intestines, kidneys, gills, brain, and eyes) and to identify and assess the carcinogenic and non-carcinogenic health risks of Arsenic (As), Cadmium (Cd), Nickel (Ni), Manganese (Mn), Cooper (Cu), Lead (Pb), Chromium (Cr) and Zinc (Zn) through the ingestion of fish (muscles and subcutaneous fat tissues). The obtained results indicated that a diet consisting of fish is particularly vulnerable, particularly in children compared to adults. The risk assessment results were below the threshold limit, although the fish samples contained heavy metals, with values exceeding the permitted limits of Fe (4.41-1604 mg/kg), Cr (727-4155 µg/kg), Zn (4.72-147 mg/kg), and Ni (333-2194 µg/kg). The studied surface waters are characterized by low and high degrees of pollution with heavy metals, as indicated by the heavy metal pollution index scores (HPI: 12.4-86.4) and the heavy metal evaluation index scores (HEI: 1.06-17.6). The considerable pollution levels are attributed to the high Mn content (0.61-49.7 µg/kg), which exceeded the limit up to fifty times. A consistent set of physico-chemical analysis (pH, electrical conductivity, total hardness, turbidity, chloride, sulphate, nitrate, nitrite, ammonium, Ca, Mg, Na, K) was analysed in water samples as well. Considering the water quality index scores (WQI: 16.0-25.2), the surface waters exhibited good quality. Microbiological results indicated the presence of Listeria monocytogenes and atypical colonies of coagulase-positive staphylococcus in fish. In contrast, the surface waters from which fish samples were collected were positive for Escherichia coli, and coliform bacteria intestinal Enterococci. Based on the study's results, it is recommended to exercise caution in the case of children related to the consumption of fish and using the waters for drinking purposes. This study provides important data of considerable novelty to the riparian population, researchers, and even policy makers on the quality status and potential levels of contamination of river waters, fish and the bioaccumulation of heavy metals in fish that may cause adverse effects on human health if consumed, and similarly the heavy metal pollution degree of waters and the non-carcinogenic risk of heavy metals through ingestion and skin absorption of water in children and adults (the study area is a significant source of fisheries).

Unveiling the ecological landscape of bacterial β-lactam resistance in Delhi-national capital region, India: An emerging health concern

Inappropriate antibiotic use not only amplifies the threat of antimicrobial resistance (AMR), moreover exacerbates the spread of resistant bacterial strains and genes in the environment, underscoring the critical need for effective research and interventions. Our aim is to assess the prevalence and resistance characteristics of β-lactam resistant bacteria (BLRB) and β-lactamase resistant bacterial genes (BLRBGs) under various environmental conditions within Delhi NCR, India. Using a culture-dependent method, we isolated 130 BLRB from 75 different environmental samples, including lakes, ponds, the Yamuna River, agricultural soil, aquatic weeds, drains, dumping yards, STPs, and gaushalas. Tests for antibiotic susceptibility were conducted in addition to phenotypic and genotypic identification of BLs and integron genes. The water and sediment samples recorded an average bacterial abundance of 3.6 × 106 CFU/mL and an average ampicillin-resistant bacterial count of 2.2 × 106 CFU/mL, which can be considered a potent reservoir of BLRB and BLRBGs. The majority of the BLRB discovered are opportunistic pathogens from the Bacillus, Aeromonas, Pseudomonas, Enterobacter, Escherichia, and Klebsiella genera, with Multiple Antibiotic Resistance (MAR) index ≥0.2 against a wide variety of β-lactams and β-lactamase (BLs) inhibitor combinations. The antibiotic resistance pattern was similar in the case of bacteria isolated from STPs. Meanwhile, bacteria isolated from other sources were diverse in their antibiotic resistance profile. Interestingly, we discovered that 10 isolates of various origins produce both Extended Spectrum BLs and Metallo BLs, as well as found harboring blaTEM, blaCTX, blaOXA, blaSHV, int-1, and int-3 genes. Enterobacter cloacae (S50/A), a common nosocomial pathogen isolated from Yamuna River sediment samples at Nizamuddin point, possesses three BLRBGs (blaTEM, blaCTX, and blaOXA) and a MAR index of 1.0, which is a major cause for concern. Therefore, identifying the source, origin and dissemination of BLRB and BLRGs in the environment is of the utmost importance for designing effective mitigation approaches to reduce a load of antimicrobial resistance factors in the environmental settings.

Synthesis and characterization of faujasite zeolite membrane for selective enrichment of Arthrobacter sp. in synthetic wastewater

This paper centers on the preparation and characterization of both a clay support and a faujasite zeolite membrane. Additionally, the study explores the development of bacterial media to assess the performance of these prepared membranes. The faujasite zeolite membrane was created using the hydrothermal method, involving the deposition of a faujasite layer to fine-tune the pore sizes of the clay support. The clay supports were crafted from clay which was sieved to particle size Φ ≤ 63 μm, and compacted with 3.0 wt.% activated carbon, then sintered at 1,000 °C. Distilled water fluxes revealed a decrease from 1,500 L m-2 h-1 to a minimum of 412 L m-2 h-1 after 180 min of filtration. Both membranes were characterized by XRF, XRD, FTIR, adsorption-desorption of nitrogen (N2), and SEM-EDS. PCR technique was used for the identification of the isolated Arthrobacter sp., and the retention of the bacteria on the clay support and the faujasite zeolite membrane were found to be 96 and 99%, respectively. The results showed that the faujasite zeolite membrane passed the clay support due to a narrow pore size of the faujasite zeolite membrane of 2.28 nm compared to 3.55 nm for the clay supports.

Assessment of the surface water quality and primary health risk in urban wastewater and its receiving river Kathajodi, Cuttack of eastern India

Kathajodi, the principal southern distributary of the Mahanadi River, is the vital source of irrigation and domestic water use for densely populated Cuttack city which receives anthropogenic wastes abundantly. This study assesses the contamination level and primary health status of urban wastewater, and its receiving river Kathajodi based on the physicochemical quality indices employing inductively coupled plasma mass spectroscopy and aligning with guidelines from the United States Environmental Protection Agency (USEPA) and WHO. The high WQI, HPI, and HEI in the catchment area (KJ2, KJ3, and KJ4) indicate poor water quality due to the influx of domestic waste through the primary drainage system and effluents of healthcare units. A high BOD (4.33-19.66 mg L-1) in the catchment indicates high organic matter, animal waste, bacteriological contamination, and low DO, resulting in deterioration of water quality. CR values beyond limits (1.00E - 06 to 1.00E - 04) in three locations of catchment due to higher Cd, Pb, and As indicate significant carcinogenic risk, while high Mn, Cu, and Al content is responsible for several non-carcinogenic ailments and arsenic-induced physiological disorders. The elevated heavy metals Cd, Cu, Fe, Mn, Ni, and Zn, in Kathajodi, could be due to heavy coal combustion, vehicle exhaust, and industrial waste. On the other hand, Cu, Fe, K, and Al could be from agricultural practices, weathered rocks, and crustal materials. Positive significant (p ≤ 0.05) Pearson correlations between physicochemical parameters indicate their common anthropogenic origin and similar chemical characteristics. A strong correlation of PCA between elements and physiological parameters indicates their role in water quality deterioration. Assessing the surface water quality and heavy metal contents from this study will offer critical data to policymakers for monitoring and managing public health concerns.

Assessing heavy metal and physiochemical pollution load of Danro River and its management using floating bed remediation

River Danro in Garhwa (India) plays a vital role as a significant source of surface water and a crucial tributary of the North Koel River, ultimately joining the Ganga River Basin. Serving both urban-industrial and rural areas, the region faces challenges, including sand mining near Belchampa Ghat. This study aimed to assess physicochemical and heavy metals pollution at nine sampling locations, utilizing the Overall Index of Pollution (OIP), Nemerow Pollution Index (NPI), and Heavy Metal Pollution Index (HPI). OIP values indicated excellent surface water quality (0.71) in non-monsoon and slight pollution (6.28) in monsoon. NPI ranged from 0.10 to 1.74 in non-monsoon and from 0.22 (clean) to 27.15 (heavily polluted) in monsoon. HPI results suggested groundwater contamination, particularly by lead. Principal component analysis (PCA) and geospatial mapping showed similar outcomes, highlighting the influence of adjacent land use on water quality. Recognizing the significance of the Danro River in sustaining life, livelihoods, and economic growth, the study recommends implementing measures like floating bed remediation and regulatory actions for effective river management. The study acknowledges weaknesses in the current practical assessment methods for water contamination. These weaknesses make it difficult to put plans for cleaning up and controlling contamination into action. Because of this, future research on developing new in-place remediation techniques should focus on creating better ways to measure how effective the cleanup is.

Geospatial quality assessment of locally available ice for heavy metals and metalloids and their potential risks for human health in Karachi, Pakistan

Extreme hot conditions during summers, high poverty rate and continuous electricity load shedding affect commercial manufacturing and sale of ice in many countries. The vendors prepared ice using untreated piped water, tanker water and ground water. These waters may contain hazardous pollutants and ice made from them will pose a potential human health risk. Thus, it is important to regularly monitor the chemical composition of water sources and the quality of the manufactured ice. A contemporary examination was carried out to evaluate the physico-chemical properties and heavy metals and metalloids in the ice sold in all the districts of Karachi, Pakistan. This pioneering study was an innovative effort to assess the ice quality in relation to potential pollutant hazards to human health; with concomitant geospatial information. The geospatial distribution of ice quality and major constituents were among the measured parameters; carefully associated with further geospatial information, determined using GIS (Geographic Information Systems) and PCA (Principal Component Analysis) techniques. Interestingly, the physico-chemical analyses revealed that the ice quality was marginally adequate and the total mean metal-metalloid contents were in the sequence of Pb > Ni > Zn > Fe > Cr > As. The concentrations of these metals were above the upper allowable limits with reference to the recommended WHO guidelines. We observed that 57.1% and 35.7% ice samples had good physico-chemical properties assessed using the Ice Quality Index (IQI). Conversely, the IQI for metals showed that the ice was unsafe for human consumption. In terms of health risk assessment, the overall mean CDI (Chronic Daily Intake) and HQ (Hazard Quotient) values were in the order of Pb () > Ni (3.2) > Zn (2.3) > Fe (2.1) > Cr (1.6) > As (0.5) and Pb (7.4) > As (1.7) > Cr (0.5) > Ni (0.4 > Zn (0.008) > Fe (0.003), respectively. This study highlighted that routine monitoring of the water supplies available for making ice is required to protect public health.

Physicochemical and bacteriological assessment of Wupa wastewater treatment plant effluent and the effluent-receiving Wupa River in Abuja, Nigeria

The occurrence of pathogens in discharged wastewater effluent may constitute potential public health risks. This study assessed the physicochemical and bacteriological characteristics of water samples taken from the Wupa River in Abuja, Nigeria, which receives the final effluent of the Wupa Wastewater Treatment Plant. Sixty sewage/water samples were collected over 12 months from five sampling points. Coliform bacteria and Escherichia coli were simultaneously enumerated using the membrane filtration technique and Chromocult Coliform Agar. HANNA multiparameter metre was used to measure the physicochemical parameters including temperature, pH, electrical conductivity (EC), dissolved oxygen (DO) and total dissolved solids (TDS). Results of the bacteriological analysis showed that impermissible high mean counts of E. coli (≥ 1.2 × 104 CFU/100 ml) and total coliforms (≥ 5.4 × 104 CFU/100 ml) were detected in 95% and 100% of the water samples respectively. These values exceed the acceptable standard limits. The mean values of physicochemical parameters ranged from 6.3 to 8.7, 20.9 to 27.3 °C, 116 to 325.0 µS/cm, 1.3 to 11.4 mg/l and 98.0 to 180.0 mg/l for pH, temperature, EC, DO and TDS respectively, with all conforming to international and national standards. Wupa River seems to have a minor negative environmental impact, per the physicochemical data obtained in this study. However, the high counts of faecal indicator bacteria demonstrated in the effluent samples were higher than those of the river at both upstream and downstream sites, implying that the river microbial load may increase to constitute an unchecked environmental hazard. Adequate disinfection of the Wupa plant effluent before discharge into the Wupa River is imperative.

Assessment of groundwater and surface water quality in a typical mining community: application of water quality indices and hierarchical cluster analyses

The rate at which freshwater sources are being contaminated by mining operations in the South-Western part of Ghana is alarming. However, no study has quantified the degree of contamination of the freshwater in such areas, leaving a gap in the literature that requires immediate attention. This study assessed the quality of the surface and groundwater in the Tarkwa Nsuaem Municipality. Even though the physical parameters such as pH and electrical conductivity were indicative of safe freshwater, other parameters such as turbidity, total suspended solids (TSS), dissolved oxygen (DO), and heavy metals in the water sources were high; thus, confirming possible leaching, runoff, and dissolution of the hazardous substances employed in the manganese mining operations. The water quality of 82% of the water sources along the Kawere Stream was low (Classes III and IV). Therefore, the local people are at risk of contracting water-related diseases, and health problems associated with the ingestion of Fe, As, and Mn. The findings in this study are important in establishing the rate at which mining operations are reducing the quality of freshwater in developing countries, and potentially affecting human health.

Water quality assessment of Remeți watercourse, Maramureș, Romania, located in a NATURA 2000 protected area subjected to anthropic pressure

The study assessed the evolution of water indicators of Remeți water body that is located in the Remeți locality in the Upper Tisa, a Natura 2000 protected area. Thus, electric conductivity, dissolved oxygen, oxygen saturation, temperature, pH, turbidity, ammonium concentration (NH₄⁺), nitrates (NO₃^-), nitrites (NO₂^-), orthophosphate (PO₄^3-), dissolved Fe, Mn, water hardness, alkalinity (A) and chloride were measured over the January (I)-October (X) 2021 period. This water course was subjected to anthropic pressure, being polluted with nutrients such as ammonium and orthophosphate ions, iron and manganese. The concentrations of other metals were either low (Al, Ba, Li, Ga, Rb, Ni, Sr, Zn, Cu, Ti) or below the detection limit (Pb, Cd). The study was performed over a period of 8 months, namely January 2021-October 2021, covering the 4 seasons, in order to establish their influence on the level of water quality indicators. Exceeded turbidity values and high concentrations of ammonium, orthophosphate and dissolved iron were found, these being generally higher in the summer-autumn months. Dissolved oxygen concentrations were low in the summer-autumn months. Based on the values of the physico-chemical indicators, two types of water quality indices WA-WQI (weighted arithmetic water quality indices) and CCME-WQI (Canadian Council of Ministers of the Environment water quality indices) were calculated to evaluate the global water quality and its evolution over the seasons with a single value. WA-WQI values varied in the range of 78.56-761.63, with a tendency to increase in autumn, showing an intensified tendency of global water quality deterioration due to an increase in ammonium, turbidity, iron and orthophosphates in autumn months while CCME-WQI values were between 39.6 and 68.9, being fair in winter-spring months and marginal / bad in summer and autumn months. The results of this study are advantageous in identifying the level of pollution of Remeți water course, being a signal for local authorities in taking the necessary measures to reduce the pollution around it, for a better human health and conservation of the ecosystems hosted in the protected area.

Deterioration of the quality of packaged potable water (bottled water) exposed to sunlight for a prolonged period: An implication for public health

The exposure of bottled water to sunlight leaches heavy metals into the water, thereby deteriorating its quality and this informed the study. Three plastic bottle brands (n = 100 per brand) were exposed to sunlight for different durations. The leaching of contaminants was exposure duration dependent. The following ranges were recorded for temperature (26.67-29.83 °C), pH (4.73-6.12), conductivity (159.00-298.67 μs/cm), turbidity (0.92-1.22 N.T.U), TDS (98.17-192.77 mg/l), hardness (38.12-78.17 mg/l), Fe (0.01-0.57 mg/l), Mn (BDL - 0.46), Cr (BDL - 0.37 mg/l), Al (BDL - 0.53 mg/l), Cd (0.02-0.21 mg/l), Zn (1.18-9.90 mg/l), Pb (0.03-1.68 mg/l), As (BDL - 1.48 mg/l), and Ni (0.05-1.55 mg/l). Health risk evaluation in all bottled water brands revealed possible Cr, Cd, Pb, As, and Ni toxicity. The carcinogenic risk of Cr, As, and, Ni, indicated potential cancer. Arsenic posed the highest non-carcinogenic risk, while Ni posed the highest carcinogenic risk in all brands after 42 days of exposure. The microbial parameters failed to meet the WHO safety limits. The exposure of bottled water to sunlight should be avoided, to ensure a healthy population.

A Portable Measurement Device Based on Phenanthroline Complex for Iron Determination in Water

In this work, a newly developed self-contained, portable, and compact iron measurement system (IMS) based on spectroscopy absorption for determination of Fe²⁺ in water is presented. One of the main goals of the IMS is to operate the device in the field as opposed to instruments commonly used exclusively in the laboratory. In addition, the system has been tuned to quantify iron concentrations in accordance with the values proposed by the regulations for human consumption. The instrument uses the phenanthroline standard method for iron determination in water samples. This device is equipped with an optical sensing system consisting of a light-emitting diode paired with a photodiode to measure absorption radiation through ferroin complex medium. To assess the sensor response, four series of Fe²⁺ standard samples were prepared with different iron concentrations in various water matrices. Furthermore, a new solid reagent prepared in-house was investigated, which is intended as a "ready-to-use" sample pre-treatment that optimizes work in the field. The IMS showed better analytical performance compared with the state-of-the-art instrument. The sensitivity of the instrument was found to be 2.5 µg Fe²⁺/L for the measurement range established by the regulations. The linear response of the photodiode was determined for concentrations between 25 and 1000 µg Fe²⁺/L, making this device suitable for assessing iron in water bodies.

In vivo degradation of polyethylene terephthalate using microbial isolates from plastic polluted environment

Accumulation of plastics alarms a risk to the environment worldwide. As polyethylene pterephthalate (PET) degrades slowly and produces hazardous substances, therefore, it is now essential to eliminate plastic wastes from the environment. Given that, the current study is concerned with PET degradation potential of naturally occurring microbial strains isolated from plastic waste dumping sites, Sarcina aurantiaca (TB3), Bacillus subtilis (TB8), Aspergillus flavus (STF1), Aspergillus niger (STF2). To test the biodegradability of PET films, the films were incubated for 60 days at 37 °C with the microorganisms designated as TB3, TB8, STF1, STF2 and the microbial consortium (TB3+TB8+STF1+STF2) in Minimal Salt Medium and Bushnell Hass Broth. Hydrophobicity, viability, and total protein content of isolates were investigated. Using Field Emission Scanning Electron Microscopy and Fourier Transform Infrared Spectrophotometry to measure variations in functional groups and carbonyl index on PET surface, biodegradation process was affirmed by fissures and modified surfaces. Results revealed that the microbial consortium (S. aurantiaca + B. subtilis + A. flavus + A. niger) that the weight loss of PET films was 28.78%. The microbial consortium could be used to treat PET waste, posing no health or environmental risks. The developed microbial consortium has the potential to degrade PET, hence can be employed for eliminating PET in plastic contaminated sites.

Quality and Health Risk Assessment of Groundwaters in the Protected Area of Tisa River Basin

This study was conducted in order to assess the chemistry (41 metalloids and heavy metals and 16 physico-chemical indicators) of groundwater sampled from the protected area of the Tisa River Basin during the months of 2021. Pollution indices were used in order to determine the potential metal pollution level. Consequently, a non-carcinogenic risk assessment of metal through the ingestion of water was done. The results indicated general contamination with ammonium, chloride, iron, and manganese. The samples were rich in Cu, Mg, and Pb, but lower than the maximum limits. Significant correlations were noticed between Al-Fe, Mn-Fe, Mn-Ni, and Cr-Zn, as well as the metal content and pollution index scores. The metal pollution indices indicated three pollution levels (low, medium, and high) based on the metal content and standards regarding the water quality used for drinking purposes. The pollution indices scores ranged from 1.52-41.2. A human health risk assessment indicated no potential non-carcinogenic risk for the studied metals through the consumption of groundwater. The results of three different tools (chronic daily intake, hazard quotient, and hazard index) were below the critical value, except for the aluminium in two samples. This study is one of the first attempts to evaluate the quality of groundwater sources associated with the human health risks of the studied metals from the Tisa River Basin protected area. Based on this research, strategies for managing and controlling the risks can be developed.

Effects of Prolonged Storage Condition on the Physicochemical and Microbiological Quality of Sachet Water and Its Health Implications: A Case Study of Selected Water Brands Sold within Samaru Community, Northwest Nigeria

The aim of this research is to investigate the effect of long-term storage conditions on the physicochemical and microbial quality of selected sachet water brands sold within the Samaru community and its health implication for consumers. Three brands of sachet water were subjected to different storage conditions and were analyzed for microbial and physicochemical parameters at intervals of 3 weeks for a period of 3 months, based on procedures and standard methods of APHA (2005). The highest pH means concentration was recorded in sachet water samples used for control (7.14 ± 0.24) while EC, TDS, BOD, and calcium (336.67 ± 73.69 µS/cm, 168.33 ± 34.89 mg/L, 1.87 ± 0.39 mg/L and 2.97 ± 0.19 mg/L) were recorded in the sachet water samples stored on the floor. A total number of 15 fungal species and 4 bacteria species were identified from the three selected brands of sachet water examined. Aspergillus niger and Penicillium spp. have the highest species occurrence of 25% among the fungus identified while Proteus Sp. recorded the highest species occurrence (50%) among the bacteria isolated. Sachet water samples stored on the floor have the highest abundances of microbial species of five and six. All the physicochemical parameters were within the stipulated limits set by the World Health Organization and the Nigeria Standard for Drinking Water Quality, but fail microbial tests due to the presence of pathogens such as Aspergillus, Candida, Vibro, Yersinia, etc., that can cause a wide range of life-threatening system infections in a patient with mild immune-deficiency. Being under prolonged storage and the type of storage conditions can encourage the regrowth of microbial in packaged water under favorable environmental conditions, to levels that may be harmful to humans.

Safe water supply challenges for hand hygiene in the prevention of COVID-19 in Southern Nations, Nationalities, and People's Region (SNNPR), Ethiopia

Background

Proper hand hygiene practices are critical in disease prevention and control, including preventing the spread of the COVID-19 pandemic, but according to a recent global report, three billion people lack access to basic hand washing facilities (soap and water) at home. Therefore, this study aimed to determine the challenges related to safe and adequate water provision for hand hygiene in the prevention of COVID-19 in Gedeo Zone, SNNPR, Ethiopia.

Methods

An institutional-based cross-sectional study design was used to assess the challenges associated with safe water supply in the prevention of COVID-19 in Gedeo Zone. Simple random sampling was used. The water sector's challenges were assessed using in-depth interviews with key informants. Water samples were collected from hand washing stations using a sterile bottle and the standard tap water sampling procedure. Bacterial analysis was carried out using membrane filtration techniques. The Wagtech Palin test and the Delagua portable water testing kit procedure was used to analyze World Health Organization (WHO) critical physicochemical parameters.

Result

The physicochemical analysis of the sample water from the hand washing facilities reveals that the pH (6.5-8) is within the WHO guideline in all samples except Gedeb town (11.1%). The residual chlorine in the samples was less than 0.2 mg/l, which is below the standard in all towns, but 15.8% of the samples in Wonago town were between 0.2-0.5mg/l. Faecal coliforms were not found in 27.5%, 21.0%, 16.6%, and 40.7% of the samples collected in Dilla, Wonago, Yirgachefe, and Gedeb town, respectively. The remaining samples were all positive for faecal coliforms. Unbalanced demand versus supply, inaccessibility, supply interruptions, financial constraints, a scarcity of competent human resources, a lack of regular water quality assessments, and a lack of stakeholder support were all identified as major challenges by all water sectors of the study towns. The majority of hand washing water samples from all of the study towns were bacteriologically unsafe. The water sector must work hard to ensure that the community has safe drinking water. All responsible bodies and potential stakeholders must support the water sectors in the Gedeo zone.

Survey of water supply and assessment of groundwater quality in the suburban communes of Selembao and Kimbanseke, Kinshasa in Democratic Republic of the Congo

In many suburban municipalities of developing countries, the household drinking water comes mainly from groundwater including, wells, streams and springs. These sources are vulnerable because poor hygienic conditions and sanitation prevail causing persistence and recurrent waterborne diseases. In this research, a survey study on water resource use and an epidemiological survey of waterborne diseases were conducted among users of water points and medical institutions in suburban communes of Selembao and Kimbanseke (Kinshasa, the Democratic Republic of the Congo). In addition, physicochemical (temperature, pH, O₂, electrical conductivity, and soluble ions: Na⁺, K⁺, PO₄ ^3-, SO₄ ^2-, NO₃ ^-, NO₂ ^-) and bacteriological (FIB: faecal indicator bacteria) analyses of water from 21 wells and springs were performed according to the seasonal variations. FIB included Escherichia coli (E. coli), Enterococcus and Total Coliforms. The survey results indicate that more than 75% of the patients admitted to local medical institutions between 2016 and 2019 are affected by waterborne diseases, including typhoid fever, amoebic dysentery, diarrhoea, gastroenteritis disorders and cholera. Except for NO₃ ^- in some sites, the water physicochemical parameter values are within WHO permissible limits for drinking/domestic water quality. On the contrary, the results revealed high FIB levels in water from unmanaged wells and springs during rainy and dry seasons. The microbiological pollution was significantly higher in the rainy season compared to the dry season. Interestingly, no FIB contamination was observed in water samples from managed/developed wells. The results from this study will guide local government decisions on improving water quality to prevent recurrent waterborne diseases.

An appraisal of data collection, analysis, and reporting adopted for water quality assessment: A case of Nigeria water quality research

The appropriate acquisition and processing of water quality data are crucial for water resource management. As such, published articles on water quality monitoring and assessment are meant to convey essential and reliable information to water quality experts, decision-makers, researchers, students, and the public. The implication is that such information must emanate from data obtained and analysed in an up-to-date, scientifically sound manner. Thus, inappropriate data analysis and reporting techniques could yield misleading results and mar the endeavours of achieving error-free conclusions. This study utilises the findings on water quality assessment in Nigeria over the last 20 years to reveal the likely trends in water quality research regarding data collection, data analysis, and reporting for physicochemical, bacteriological parameters, and trace organics. A total of 123 Web of Science and quartile ranked (Q1-Q4) published articles involving water quality assessment in Nigeria were analysed. Results indicated shortcomings in various aspects of data analysis and reporting. Consequently, we use simulated heatmaps and graphs to illustrate preferred ways of analysing, reporting, and visualising some regularly used descriptive and inferential statistics of water quality variables. Finally, we highlight alternative approaches to the customarily applied water quality assessment methods in Nigeria and emphasise other areas of deficiency that need attention for improved water quality research.

Assessment of microbial and heavy metal contamination in shallow hand-dug wells bordering Ona River, Southwest Nigeria

Ona River is one of the three major rivers draining the city of Ibadan. Groundwater is the major source of drinking water in the metropolis; however, data on quality of shallow aquifers bordering Ona River is relatively scarce. This study aimed to evaluate bacteriological status, heavy metal content, and associated human and ecological health risks in hand-dug wells nearby Ona River. A total of 24 water samples from 12 sampling points were collected for chemical and microbial analyses. Heavy metals and microbial pathogens were analyzed using atomic absorption spectrometry and total plate count methods, respectively. Analyses of microbial and heavy metal (HMs) data showed that shallow hand-dug wells within the vicinity of Ona River were bacteriologically contaminated while most of analyzed heavy metals (except manganese) exceeded the drinking water quality standards. Interpretation of microbial and heavy metal (HMs) data identified predominance of anthropogenic activities as the major source of contamination in drinking water. Further scrutiny of HM data through integrated pollution indices identified two nearby wells (S₇ and S₈) exceed the safe limits and pose considerable risk to inhabitants. In terms of ecological risk index (ER), cadmium exhibited considerable to very high ER in all collected samples while manganese and zinc showed low ER in all analyzed water samples. Potential of non-carcinogenic risk through ingestion pathway in the study area was identified with the order of contributive ratios by HMs as Cd > Pb > Zn > Fe > Mn. The calculated target hazard quotient (THQ) due to ingested HMs for three human population categories exceeds the safe limit in the order of adult < children < infants. The study revealed the deteriorated state of waterside shallow hand-dug wells that need immediate actions by relevant stakeholders in water management. The study recommends improved hygienic practices, pretreatment of water before use, and most importantly, provision of potable pipe-borne water supply to the residents of the study area.