Exploring the use of clay pots as sustainable storage containers to improve water quality

BACKGROUND

Currently, tap water consumption is not highly preferred in Egypt and around the world. People prefer to consume bottled water because they believe that it is much safer and tastes better than tap water. Unfortunately, this preference can create an economic burden for many people, especially in developing countries. Clay pots can be used to provide cool, alkaline drinking water because of their porous micro-texture, which traps pollutants. This study aimed to investigate the use of clay pots to store tap water and its impact on the requirements for drinking water quality. This is done with the intent to decrease the need for bottled water as a means of offering a more sustainable and economical option.

METHODS

In this study, the efficiency of clay pots as sustainable storage containers for drinking water was tested by measuring physicochemical parameters (pH, TDS, EC, turbidity, DO, ammonia, chloride, total hardness, Ca hardness, Mg hardness, chlorine, Zn, and CaCO3) and biological parameters (TPC and Legionella).

RESULTS

After 7 days of storage, the quality of the water stored in clay pots met the standards set by the Egyptian law with a significant difference (p < 0.05) before and after the storage of water It was found that the dissolved oxygen increased from 6.17 ppm to 7.52 ppm after 7 days. As for total hardness, it declined from 195 to 178 ppm. There was also a significant drop in terms of TDS from 338 to 275 ppm. Furthermore, clay pots effectively filtered out both total viable bacteria and Legionella.

CONCLUSION

This study proved the efficiency of using these containers with respect to some indicator values for tap water and tank water analysis. Clay pots are an excellent, cost-effective, and sustainable alternative for storing water.

Assessing the geochemical processes controlling groundwater quality and their possible effect on human health in Patna, Bihar

This research was conducted in the urban area of Patna region, the capital and largest city of Bihar, which is part of the Indo-Gangetic alluvium plain. This study aims to identify the sources and processes controlling groundwater's hydrochemical evolution in the Patna region's urban area. In this research, we evaluated the interplay between several measures of groundwater quality, the various possible causes of groundwater pollution, and the resulting health risks. Twenty groundwater samples were taken from various locations and examined to determine the water quality. The average EC of the groundwater in the investigated area was 728 ± 331.84 µS/cm, with a range of around 300-1700 µS/cm. Positive loadings were seen for total dissolved solids (TDS), electrical conductivity (EC), calcium (Ca2+), magnesium (Mg2+), sodium (Na+), chloride (Cl-), and sulphate (SO42-) in principal component analysis (PCA), demonstrating that these variables accounted for 61.78% of the total variance. In the groundwater samples, the following main cations are the most prevalent such as Na+  > Ca2+  > Mg2+  > K+, while the dominant anions are HCO3-  > Cl-  > SO42-. The elevated HCO3- and Na+ ions indicate that carbonate mineral dissolution might affect the study area. The result demonstrated that 90% of samples fall into the Ca-Na-HCO3 type, remaining in the mixing zone. The presence of the NaHCO3 kind of water is suggestive of shallow meteoric water, which may have originated from the river Ganga that is located nearby. The results show that a multivariate statistical analysis and graphical plots successfully identify the parameters controlling groundwater quality. In accordance with guidelines for safe drinking water, the electrical conductivity and potassium ion concentrations in the groundwater samples are 5% higher than acceptable levels. People who take large amounts of salt replacements report feeling tight in the chest, vomiting, having diarrhoea, developing hyperkalaemia, having trouble breathing, and even experiencing heart failure.

Relic DNA obscures DNA-based profiling of multiple microbial taxonomic groups in a river-reservoir ecosystem

Numerous studies have investigated the spatiotemporal variability in water microbial communities, yet the effects of relic DNA on microbial community profiles, especially microeukaryotes, remain far from fully understood. Here, total and active bacterial and microeukaryotic community compositions were characterized using propidium monoazide (PMA) treatment coupled with high-throughput sequencing in a river-reservoir ecosystem. Beta diversity analysis showed a significant difference in community composition between both the PMA untreated and treated bacteria and microeukaryotes; however, the differentiating effect was much stronger for microeukaryotes. Relic DNA only resulted in underestimation of the relative abundances of Bacteroidota and Nitrospirota, while other bacterial taxa exhibited no significant changes. As for microeukaryotes, the relative abundances of some phytoplankton (e.g. Chlorophyta, Dinoflagellata and Ochrophyta) and fungi were greater after relic DNA removal, whereas Cercozoa and Ciliophora showed the opposite trend. Moreover, relic DNA removal weakened the size and complexity of cross-trophic microbial networks and significantly changed the relationships between environmental factors and microeukaryotic community composition. However, there was no significant difference in the rates of temporal community turnover between the PMA untreated and treated samples for either bacteria or microeukaryotes. Overall, our results imply that the presence of relic DNA in waters can give misleading information of the active microbial community composition, co-occurrence networks and their relationships with environmental conditions. More studies of the abundance, decay rate and functioning of nonviable DNA in freshwater ecosystems are highly recommended in the future.

Assessment of potential health risks from heavy metal pollution of surface water for drinking in a multi-industry area in Mali using a multi-indices approach

The Niger River, Bamako's population's primary drinking water source, is threatened by human activities. This study examines the Niger River pollution trend using heavy metals pollution indexes and Bamako's population's non-carcinogenic and carcinogenic related health risks. Parameters were monitored at fifteen sampling locations in low and high flow seasons. pH (7.30-7.50) and fluoride (0.15-0.26 mg/L) were within the normal drinking water range. Among seven heavy metals (copper, zinc, cadmium, nickel, iron, manganese, and lead), the latter three were above the drinking water standard. The degree of contamination was negative, pointing to better water quality. However, the heavy metal evaluation index (HEI) was below the mean (5.88), between the mean and twice the mean, indicating a low and medium degree of pollution. Besides, heavy metal pollution indexes (HPI) were above the standard value (100), explaining a low-medium pollution level. High values of HPI could be explained by the industrial units' intensive activities coupled with the runoff effect. The hazard index (HI) indicated a low and medium non-carcinogenic health risk for adults and children. The probability of cancer risk (PCR) of nickel showed a cancer risk. Therefore, the river was polluted with trace elements and could not be used for drinking water without any treatment.

Development of an Improved Sulfur-Oxidizing Bacteria-Based Ecotoxicity Test for Simple and Rapid On-Site Application

Microbial toxicity tests are considered efficient screening tools for the assessment of water contamination. The objective of this study was to develop a sulfur-oxidizing bacteria (SOB)-based ecotoxicity test with high sensitivity and reproducibility for simple and rapid on-site application. To attain this goal, we developed a 25 mL vial-based toxicity kit and improved our earlier SOB toxicity test technique. The current study applied a suspended form of SOB and shortened the processing time to 30 min. Moreover, we optimized the test conditions of the SOB toxicity kit in terms of initial cell density, incubating temperature, and mixing intensity during incubation. We determined that 2 × 10⁵ cells/mL initial cell density, 32 °C incubating temperature, and 120 rpm mixing intensity are the optimal test conditions. Using these test conditions, we performed SOB toxicity tests for heavy metals and petrochemicals, and obtained better detection sensitivity and test reproducibility, compared to earlier SOB tests. Our SOB toxicity kit tests have numerous advantages, including a straightforward test protocol, no requirement of sophisticated laboratory equipment, and no distortion of test results from false readings of end-points and properties of test samples, making it suitable for simple and rapid on-site application.

Hydrochemical appraisal of surface water from a subtropical urban river in southwestern Bangladesh using indices, GIS, and multivariate statistical analysis

The Gorai River is a significant river  in Bangladesh's southwestern region, where residents make great use of the water despite a lack of adequate and reliable information concerning water quality and pollution levels. Thus, the goal of this research was to examine the spatio-temporal variations in water quality and determine whether it was suitable for drinking, agriculture, industrial, or livestock purposes, as well as the influencing factors and potential sources of water pollution. Surface water samples were collected in wet and dry seasons from ten sampling sites, and twenty water quality parameters were evaluated. The results showed that some studied water quality parameters, e.g., temperature, electrical conductivity, alkalinity, and nitrate, exceeded the maximum allowable limit. Water quality index values exhibited that the water quality of all sampling sites was found to be poor to very poor during the wet season, while only St-4 and St-5 were found to be poor and the rest of the investigated sites were good category during the dry season. Based on sodium adsorption ratio, soluble sodium percentage, residual sodium carbonate, residual sodium bicarbonate, and permeability index values, it was depicted that river water was suitable for irrigation purposes, but when compared to Kelly's ratio (KR) and magnesium hazard ratio values, river water was found to be unfit for irrigation. Moreover, potential salinity (PS) and sodium-to-calcium activity ratio (SCAR) values allow the water as moderately suitable for use in irrigation purposes. Langelier saturation index (LSI) and aggressive index (AI) values revealed that the river water was under saturated to supersaturated and moderate to non-aggressive in nature. However, Ryznar stability index (RSI), Puckorius scaling index (PSI), and Larson-Skold index (LS) values describe whether the water was high or severely corrosive, signifying its inappropriateness for industrial consumption. Principal component analysis (PCA) analysis depicted that the fluctuations in water quality are mostly related to point and non-point contaminations, such as urban and industrial effluent discharged and agricultural runoff of fertilizers. Cluster analysis (CA) revealed relative geographical and seasonal changes in water quality, showing the impact of hydrological changes and contamination.

A preliminary assessment of spatial variation of water quality of Ratuwa river

This work helps to identify the source of pollution in water and characterize the water quality which is essential to water management for sustainable development. Therefore, the main objective of this work is to evaluate the spatial distribution of the water quality of Ratuwa river and its tributaries. The water samples were collected from six discrete sampling locations and fifteen parameters were tested using respective well-calibrated equipment and standard APHA methods. The physicochemical analysis, water quality index, and correlation matrix method were employed to evaluate the spatial variation of the water quality of Ratuwa river. Turbidity was the most polluting factor in river water. The results showed the spatial variation of the water quality index (WQI) from 39.3 to 70.5, which fell in the range of "good" to "poor" water quality status. None of the water samples was either "excellent" or "unsuitable for drinking." The water quality was "Poor" upstream and downstream of Ratuwa river due to the high value of turbidity. Chaju river was found to have unpolluted whereas Dipeni river was slightly polluted due to domestic and municipal wastes. Hence, the deterioration of water quality can be attributed to natural and anthropogenic sources.

Physiochemical Analysis of Drinking Water and Treatment with a Homemade Filter: A Case Study of Illu Abba Bor Zone, Ethiopia

The drinking water quality was evaluated in order to provide a continuous supply of clean and safe drinking water for the preservation of public health. The study area consists of three villages: Tulube, Seddo, and Serdo, all of which are located near Mettu town, which is about 550 kilometers south-west of Ethiopia's capital, Addis Ababa. The physical and chemical parameters of the collected drinking water samples were assessed, including pH, turbidity, conductivity, total suspended solids (TSS), total dissolved solids (TDS), and the presence of heavy metals. The samples were examined in the laboratory, and the findings were compared to the World Health Organization (WHO) standards. Almost all of the physiochemical indicators were safe and within the permissible limit for drinking water quality. However, lead ion concentrations were found to be above the WHO standards. An adsorbent produced from banana pseudostems was used to remove lead ions from drinking water. The equilibrium parameters were determined using the Langmuir adsorption isotherm. The drinking water was treated for 4 h in a homemade adsorption column composed of filter medium (sand, charcoal, and powder of treated banana pseudostem). The data revealed that lead ions removal was nearly 70%, but still above the WHO standards.

Analytical Review on Membrane Water Filter using Different Materials to Prevent Microbial Activities

Drinking water quality monitoring technologies have made significant progress in monitoring water resources and water treatment plants. This paper discusses the adverse effect of microbial contamination and also gives a brief description of the important parameters for drinking water and the technologies currently available used in this field. This paper is focused on studying the requirement for the development of low-cost filter materials that can be suitable as well as economical to be produced on a large-scale for real applications. There are several parameters such as porosity, contact angle, water flux, thickness, microbial activity needed to be focused on in the future to study the transformation of the hydrophilic property on the surface of the water.

Comprehensive evaluation of the possible impact of roofing materials on the quality of harvested rainwater for human consumption

Water is a vital natural resource that influences life and contributes to domestic and industrial activities. Availability and accessibility of safe water sources are crucial for a country's economic growth. Harvesting of roof runoffs is an alternative source of water used for domestic purposes. However, the quality of harvested rainwater can be affected by roofing materials. This research seeks to assess heavy metals concentration, physicochemical and bacteriological parameters in roof runoffs and estimate the water quality index and health risk these metals pose to consumers. Rainwater samples were collected from Aluzinc, Aluminum, Galvanized, and Asbestos roofing materials within the Ejisu municipality. Rainwater collected directly from the sky was used as control. All runoffs from the four roofing materials recorded Cd, Fe, Cr, turbidity, pH, E.coli, total and fecal coliform levels above WHO limit for drinking water. There was a significant variation in pH, EC, Zn, Cd, Cr, Fe, E. coli, total and fecal coliform levels between control samples and roof runoffs (p < 0.05). The estimated water quality index for runoffs from the four roofing materials exceeded 100 indicating their unsuitability for drinking. Cadmium recorded the highest non-cancer health risk to children and adults in all the roof runoffs. Hazard quotients (HQs) above one were recorded for a child (HQ = 40.1) and an adult (HQ = 13.6) via dermal exposure to Cd in runoff from Aluminum roofing material. Hazard quotient of 9.53 and 4.08 were estimated for a child and an adult respectively via oral exposure to Cd in runoffs from Asbestos roofing material. The estimated cancer risks were above 10^-3 for a child and an adult via oral and dermal exposure to Cd in all roof runoffs, suggesting a possible cancer health effect. The study concludes that the four roofing materials impact negatively on the quality of runoffs.

Advances in Technological Research for Online and In Situ Water Quality Monitoring—A Review

Monitoring water quality is an essential tool for the control of pollutants and pathogens that can cause damage to the environment and human health. However, water quality analysis is usually performed in laboratory environments, often with the use of high-cost equipment and qualified professionals. With the progress of nanotechnology and the advance in engineering materials, several studies have shown, in recent years, the development of technologies aimed at monitoring water quality, with the ability to reduce the costs of analysis and accelerate the achievement of results for management and decision-making. In this work, a review was carried out on several low-cost developed technologies and applied in situ for water quality monitoring. Thus, new alternative technologies for the main physical (color, temperature, and turbidity), chemical (chlorine, fluorine, phosphorus, metals, nitrogen, dissolved oxygen, pH, and oxidation–reduction potential), and biological (total coliforms, Escherichia coli, algae, and cyanobacteria) water quality parameters were described. It was observed that there has been an increase in the number of publications related to the topic in recent years, mainly since 2012, with 641 studies being published in 2021. The main new technologies developed are based on optical or electrochemical sensors, however, due to the recent development of these technologies, more robust analyses and evaluations in real conditions are essential to guarantee the precision and repeatability of the methods, especially when it is desirable to compare the values with government regulatory standards.

Water quality assessment and evaluation of human health risk of drinking water from source to point of use at Thulamela municipality, Limpopo Province

Water quality has been linked to health outcomes across the world. This study evaluated the physico-chemical and bacteriological quality of drinking water supplied by the municipality from source to the point of use at Thulamela municipality, Limpopo Province, South Africa; assessed the community practices regarding collection and storage of water and determined the human health risks associated with consumption of the water. Assessment of water quality was carried out on 114 samples. Questionnaires were used to determine the community’s practices of water transportation from source to the point-of-use and storage activities. Many of the households reported constant water supply interruptions and the majority (92.2%) do not treat their water before use. While E. coli and total coliform were not detected in the water samples at source (dam), most of the samples from the street taps and at the point of use (household storage containers) were found to be contaminated with high levels of E. coli and total coliform. The levels of E. coli and total coliform detected during the wet season were higher than the levels detected during the dry season. Trace metals’ levels in the drinking water samples were within permissible range of both the South African National Standards and World Health Organisation. The calculated non-carcinogenic effects using hazard quotient toxicity potential and cumulative hazard index of drinking water through ingestion and dermal pathways were less than unity, implying that consumption of the water could pose no significant non-carcinogenic health risk. Intermittent interruption in municipal water supply and certain water transportation and storage practices by community members increase the risk of water contamination. We recommend a more consistent supply of treated municipal water in Limpopo province and training of residents on hygienic practices of transportation and storage of drinking water from the source to the point of use.

Effect of environmental factors on blood counts of Gambusia affinis caught at Brantas River watershed, Indonesia

Background: Contamination of freshwater ecosystems has become a major issue as it threatens public water sources as well as aquatic life. It is important to predict changes in organism health, given a known number of environmental factors and pollutant concentrations, in order to better manage contaminants through biomarker analysis. This study aims to examine the ecosystem health of the Brantas River based on its environmental condition and the hematology profile of Gambusia affinis fish present in the river. This species was chosen because of its wide distribution along the Brantas River, and because it is very tolerant, adaptable, highly abundant, and easy to catch.

Methods: The study area included 10 sampling sites along the Brantas River watershed. In total, six water quality parameters were observed (temperature, pH, dissolved oxygen (DO), biological oxygen demand (BOD), ammonia concentration, and phenol concentration) and hematology measurements consisted of erythrocyte, leucocyte, and micronuclei analyses.

Results: The results showed that the upstream area of Brantas River, located in Batu, was the least polluted region, while Mojokerto was the most polluted. The erythrocyte level of Gambusia affinis caught in most sampling sites was quite low. Furthermore, research revealed that the status of Gambusia affinis' hematological profile was significantly correlated (p<0.05) with water quality parameters, particularly DO, BOD, ammonia, and phenol.

Conclusions: It can be concluded from these results that the hematological profile of the fish is poor due to high levels of organic waste and harmful substances.

Using physicochemical and biological parameters for the evaluation of water quality and environmental conditions in international wetlands on the southern part of Lake Urmia, Iran

The Kani Barazan and Yadegarlou wetlands in the southern part of Lake Urmia (Iran) have been substantially modified due to human activities and anthropogenic use. In recent years, freshwater-based eco-biological studies to recognize the quality of water resources have been greatly expanded. Microalgae and Cyanophyta are considered important bioindicators for the evaluation of water quality and wetland health worldwide. Herein, 22 microalgae and 5 Cyanophyta genera were identified in both wetlands, in which Cyanophyta has mainly caused blooms. Principal components analysis (PCA) was carried out based on links between the distribution of microalgae and Cyanophyta with physical and chemical parameters. The data showed that depth, turbidity, and the temperature had a significant influence on the microalga and Cyanophyta communities in both wetlands. Based on the biological properties, it seems that the Kani Barazan and Yadegarlou international wetlands experience meso-eutrophic conditions. The integration of the physical, chemical and biological parameters with the water quality index (WQI) revealed that both wetlands were polluted as a consequence of human activities. Moreover, a close relationship between WQI and the biological parameters was documented. Thus, we concluded that microalgae and Cyanophyta communities, their abundance patterns, and water quality changes could provide valuable data for the conservation of the Kani Barazan and Yadegarlou international wetlands.

Ganga river water quality assessment using combined approaches: physico-chemical parameters and cyanobacterial toxicity detection with special reference to microcystins and molecular characterization of microcystin synthetase (mcy) genes carrying cyanobacteria

Water quality assessment relies mostly on physico-chemical-based characterization; however, eutrophication and climate change advocate the abundance of toxic microcystins (MCs) producing cyanobacteria as emerging bio-indicator. In the present study, a spatial-temporal analysis was carried out at ten sampling sites of Prayagraj and Varanasi during June 2017 and March 2018 to determine the Ganga River water quality using physico-chemical parameters, cyanobacteria diversity, detection of MCs producing strains and MC-LR equivalence. Coliform bacteria, COD, NO₃-N, and phosphate are the significant contaminated parameters favoring the growth of putative MCs producing cyanobacteria. National Sanitation Foundation WQI (NSFWQI) indicates water quality, either bad or medium category at sampling points. The morphological analysis confirms the occurrence of diverse cyanobacterial genera such as Microcystis, Anabaena, Oscillatoria, and Phormidium. PCR amplification affirmed the presence of toxic microcystin (mcy) genes in uncultured cyanobacteria at all the sampling sites. The concentration of MC-LR equivalence in water samples by protein phosphatase 1 inhibition assay (PPIA) and high-performance liquid chromatography (HPLC) methods was observed in the range of 23.4-172 ng/L and 13.2-97.5 ng/L respectively which is lower than the harmful exposure limit by World Health Organization (WHO). Ganga isolate 1 was identified as Microcystis based on partial 16S rDNA sequence and its toxicity was confirmed due to presence of mcy genes and MCs production potential. These findings suggest the presence of MCs producers as new emerging parameter to monitor water quality index and identification up to species level will be valuable for restoration strategies of river Ganga.

Investigating the Influence of Column Depth on the Treatment of Textile Wastewater Using Natural Zeolite

Textile industry production processes generate one of the most highly polluted wastewaters in the world. Unfortunately, the field is also challenged by the availability of relatively cheap and highly effective technologies for wastewater purification. The application of natural zeolite as a depth filter offers an alternative and potential approach for textile wastewater treatment. The performance of a depth filter treatment system can be deeply affected by the column depth and the characteristics of the wastewater to be treated. Regrettably, the information on the potential of these filter materials for the purification of textile wastewater is still scarce. Therefore, this study investigated the potential applicability of natural zeolite in terms of column depth for the treatment of textile wastewater. From the analysis results, it was observed that the filtration efficiencies were relatively low (6.1 to 13.7%) for some parameters such as total dissolved solids, electrical conductivity, chemical oxygen demand, and sodium chloride when the wastewater samples were subjected to the 0.5 m column depth. Relatively high efficiency of 82 and 93.8% was observed from color and total suspended solids, respectively, when the wastewater samples were subjected to the 0.5 m column depth. Generally, the 0.75 m column depth achieved removal efficiencies ranging from 52.3% to 97.5%, whereas the 1 m column depth achieved removal efficiencies ranging from 86.9% to 99.4%. The highest removal efficiency was achieved with a combination of total suspended solids and 1 m column depth (99.4%). In summary, the treatment approach was observed to be highly effective for the removal of total suspended solids, with a 93.8% removal efficiency when the wastewater was subjected to the 0.5 m column depth, 97.5% for 0.75 m column depth, and 99.4% for 1 m column depth. Moreover, up to 218.233 mg of color per g of the filter material was captured. The results derived in this study provide useful information towards the potential applicability of natural zeolite in the textile wastewater treatment field.

Effects of effluent discharges from a cement factory on the ecology of macroinvertebrates in an Afrotropical river

Cement factory waste water impacts on the ecology of macroinvertebrate assemblages of the Oinyi River, North Central area of Nigeria, were evaluated bi-monthly for 1 year as part of a study to understand the effects of pollution processes in the lotic system that may initiate the development of policy and improved regulation. Three sampling stations, each 100 m long, were selected along 11-km stretch of the river. Station 1, located upstream of the discharge point from the cement factory plant; station 2, immediately downstream of the effluent discharge point; and station 3, 4 km downstream, were sampled. The waste water from the cement effluent factory impacted negatively on the water chemistry by elevating the levels of some heavy metals (Mn, Zn, Cu, and Ni), and other physicochemical parameters such as turbidity, chemical oxygen demand (COD), conductivity, and total suspended solid. A total of 81 macroinvertebrate taxa combined were recorded from the river. The community structure, diversity, and abundance depicted distinct variation between the effluent-impacted site, and the upstream station as the most sensitive macroinvertebrate taxa such as Neoperla and Cheumatopsyche species was completely missing from the effluent-impacted site. The preponderance of some dipteran taxa (Tanypus sp., Eristalis tenax, Simulum sp., Empis sp., and Atherix sp.) and drastic reduction in the Ephemeroptera-Plecoptera-Trichoptera (EPT) organisms in the impacted station is an indication that the chemical components of the cement effluent waste water were lethal to some aquatic forms. Extrapolations from canonical correspondence analysis (CCA) results revealed that turbidity, conductivity, BOD, orthophosphate-phosphorus, and heavy metals were strongly associated with the impacted station. Generally, the community structure of station 1 was more diverse with more sensitive taxa, different from those of stations 2 and 3, which were prone to intense human activities. The need for careful consideration of the water quality and indicator organisms is important for restoration of this river.

Non alcoholic palm nectar from Cocos nucifera as a promising nutraceutical preparation

Nonalcoholic Palm Nectar from Cocos nucifera (NPNC), a bio-refresher obtained from the juvenile inflorescence of coconut palm; is prominent as a nutritional health drink. The aim of this study was to investigate the nutritional and medicinal properties of NPNC and its products; sugar (NPNCS) and honey (NPNCH). The collected samples were subjected to physicochemical evaluations such as pH, Titrable Acidity, Total Soluble Solids, and Ash value, using standard techniques. The analysis revealed the suitability of NPNC as a natural health drink over conventionally available beverage. The elemental compositions of the samples were determined by using Inductive Coupled Plasma-Atomic Emission Spectrometry and demonstrated that NPNCH is enriched with iron and NPNCS with calcium. Vitamin C present in the samples was determined by using 2,6-Dichlorophenol indophenol redox titration method. Hydrolysable polyphenols, tannins, and flavonoids are determined by Folin-Ciocalteu, by Folin-Denis's technique and by aluminium chloride colorimetric methods, respectively. In NPNC, the dominance of Vitamin C as antioxidant is observed. Diuretic activity of samples was determined by Lipschitz method, and the results revealed that NPNC exhibited significant diuretic activity, comparable with furosemide. Immunomodulatory activities of the samples were evaluated by using indirect hemagglutination test and by using delayed type hypersensitivity (DTH) response. NPNC, NPNCS, and NPNCH exhibited stimulatory effect on humoral and cell-mediated immunity, which is comparable with that of standard immunomodulator levamizole. Subacute toxicity studies of selected samples were done in Wistar rats and the results proved the boicompatibility of the samples without systemic toxic effects. PRACTICAL APPLICATIONS: The use of commercially available carbonated beverages and energy drinks in young adults are associated with negative health outcomes with increased incidence of diabetes, sleep disturbances, and dental problems. Even though, such complications are there, the energy drink industries have grown dramatically accounting for major percentage of market sale. Researchers are in search for natural health drinks with some medicinal value to avoid the negative impact on consumers' health. Nonalcoholic Palm Nectar from Cocos nucifera (NPNC) is considered as zero alcoholic natural health drink. The focus of this study is to reveal the potential medicinal properties of NPNC and its products; honey (NPNCH) and sugar (NPNCS). If the nutritional and medicinal values of the selected preparations from natural sources can be proved with scientific evidence, its ability to beat commercially available carbonated beverages and energy drinks with negative health consequences may get widespread acceptance.

Treatment of Poultry Slaughterhouse Wastewater with Membrane Technologies: A Review

Poultry slaughterhouses produce a large amount of wastewater, which is usually treated by conventional methods. The traditional techniques face some challenges, especially the incapability of recovering valuable nutrients and reusing the treated water. Therefore, membrane technology has been widely adopted by researchers due to its enormous advantages over conventional methods. Pressure-driven membranes, such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO), have been studied to purify poultry slaughterhouse wastewater (PSWW) as a standalone process or an integrated process with other procedures. Membrane technology showed excellent performance by providing high efficiency for pollutant removal and the recovery of water and valuable products. It may remove approximately all the pollutants from PSWW and purify the water to the required level for discharge to the environment and even reuse for industrial poultry processing purposes while being economically efficient. This article comprehensively reviews the treatment and reuse of PSWW with MF, UF, NF, and RO. Most valuable nutrients can be recovered by UF, and high-quality water for reuse in poultry processing can be produced by RO from PSWW. The incredible performance of membrane technology indicates that membrane technology is an alternative approach for treating PSWW.

Quality and Safety of Rural Community Drinking Water Sources in Guto Gida District, Oromia, Ethiopia

The quality of drinking water has always been a major public health concern, especially in developing countries where access to improved water supply and sanitation is very low. This study aimed to assess the bacteriological and physicochemical quality of rural community drinking water sources in the Guto Gida district. A cross-sectional study was conducted in selected rural areas of the district from January to June 2016. Water samples were collected from four types of sources (protected dug well, open dug well, protected spring, and open spring) found in 8 locations of the study area. The membrane filtration technique was employed to determine the total coliform and faecal coliform load of the samples. The physicochemical characteristics such as total dissolved solid (TDS), pH, electrical conductivity (EC), turbidity, temperature, color, iron, manganese, lead, fluoride, zinc, sulphate, nitrate, and phosphate were analyzed following the American Public Health Association and WHO standard protocols. Our results revealed that 90.6% and 87.5% of water samples were positive for total coliform and faecal coliform, respectively. Thus, the majority of the studied water sources could be classified as polluted with respect to coliform load. Our results also have shown that most of the water sources showed marginally tolerable quality with respect to color, EC, TDS, turbidity, nitrate, sulphate, and phosphate. However, the protected sources had poor quality in zinc, lead, iron, manganese, and pH with values above the permissible levels. Thus, the drinking water source quality of the study areas requires appropriate interventions such as improving the existing water source infrastructure and access to sanitation services.

Assessment of Some Physicochemical Parameters and Heavy Metals in Hand-Dug Well Water Samples of Kafta Humera Woreda, Tigray, Ethiopia

Groundwater is one of the most important sources of drinking water in Kafta Humera Woreda; hence, it is important to assess the quality of these water sources. The aim of this study was to assess the levels of some physicochemical parameters and heavy metals in hand-dug well water sources of Kafta Humera Woreda. The results showed that the physicochemical concentrations of the hand-dug well water samples were given as follows: temperature, 27.67 ± 0.15 to 28.30 ± 0.25°C; pH, 6.90 ± 0.33 to 8.20 ± 0.36; dissolved oxygen, 5.60 ± 0.06 to 6.2 ± 0.04 mg/L; turbidity, 1.67 ± 0.02 to 1.89 ± 0.03 NTU; EC, 148.50 ± 0.89 to 932.00 ± 0.98 μS/cm; TDS, 105.80 ± 0.62 to 664.28 ± 0.70 mg/L; total hardness, 71.80 ± 3.05 to 295.30 ± 2.38 mg/L; total alkalinity, 75 ± 5.0 to 215 ± 5.0 mg/L; calcium, 12.02 ± 0.82 to 75.88 ± 0.93 mg/L; magnesium, 9.80 ± 0.80 to 25.70 ± 0.17 mg/L; potassium, 0.130 ± 0.003 to 0.86 ± 0.04 mg/L; sodium, 2.20 ± 0.16 to 12.75 ± 0.87 mg/L; chloride, 12.86 ± 0.02 to 42.72 ± 0.20 mg/L; sulfate, 17.24 ± 0.96 to 118.67 ± 0.46 mg/L; phosphate, 0.018 ± 0.005 to 0.020 ± 0.002 mg/L; and nitrate, 1.86 ± 0.03 to 5.43 ± 0.06 mg/L. Generally, the concentrations of most physicochemical parameters of the hand-dug well water samples of Kafta Humera Woreda were within the permissible limit of World Health Organization and Ethiopian Standard Agency guideline for drinking water. The statistical Pearson's correlation analysis on the water quality parameters revealed that all parameters are more or less correlated with each other. Electrical conductivity and total dissolved solids of the water samples were found to be significantly correlated with total hardness (r = 0.989), total alkalinity (r = 0.827), calcium (r = 0.988), magnesium (r = 0.881), sodium (r = 0.995), potassium(r = 0.996), chloride (r = 0.998), sulfate (r = 1), and nitrate ions (r = 0.972). Out of the selected seven heavy metals, Fe, Cu, Zn, Mn, Cr, Cd, and Pb, only iron was detected in all water samples and its concentration was above the permissible limit of WHO and ESA for drinking water. Therefore, the government should adopt some treatment technologies such as sedimentation and aeration to minimize the concentration of iron for safe drinking the water to the community of Kafta Humera Woreda.

Impact of some beverage industries on the physicochemical characteristics of Ajali River in Enugu, Nigeria

Ajali River near some beverage industries was assessed. Eleven physicochemical parameters and six heavy metals (copper, zinc, iron, cadmium, chromium, and lead) were analyzed on water and sediment collected from different locations near three beverage industries. Standard methods were used to determine the physicochemical parameters while heavy metals were determined with atomic absorption spectrophotometer. The health risk assessment of the water samples were estimated by calculating the hazard quotient (HQ), total hazard index (THI), and the probability cancer risk (PCR) of the heavy metals. Results showed that the concentrations of some heavy metal and physicochemical properties were slightly impaired compared to permissible standards. However, cadmium in water (0.56-11.34 mg/L) and sediments (2.81-481.40 mg/kg) samples were above the recommended limit, indicating possible cadmium pollution in the study area. The water quality index values showed that some of the sampled locations had poor (53.43-134.90%) water quality. The risk assessment of the water samples revealed that HQ for Cu, Zn, Fe, and Cr were of no probable risk (HQ < 1) while Cd (HQ = 173-438) were of probable risk. THI of the water samples showed probable risk (THI > 1) resulting from the high percentage contribution of Cd (94.13 to 99.95%). The probability carcinogenic risk assessment for adults (Cd-7.14 × 10^-2, Cr-1.43 × 10^-4) and children (Cd-1.66 × 10^-1 and Cr-3.34 × 10^-4) were significantly harmful. Even though the presence of these industries could encourage more economic activities in the area, there is need for the relevant agencies to enforce effective treatment and proper management of wastes especially cadmium, to safeguard this water source for the rural dwellers.

Effects of Contamination of Freshwater Habitat With Common Heavy Metals and Anions on the Prevalence of Human Adenoviruses and Enteroviruses

The occurrence and survival of enteric viruses in open surface waters can be impacted by a host of factors including fecal emission levels, seasonal variations, virus stability and the physicochemical parameters. In this research, we aimed to document the association between contaminations of water samples with human enteric viruses (adenoviruses and enteroviruses) from a freshwater lake with variations in chemical contaminants. We collected 216 water samples from October 2010 to April 2012, from a 4 km stretch along Lake Victoria (LV) basin in Homa Bay town located in the western region of Kenya. The samples were analyzed for the existence of human adenoviruses (HAdV) and human enteroviruses (HEV), using the nested PCR (nPCR). We also assessed in the water samples the levels of twelve chemical contaminants consisting of six heavy metal elements and six anions. About 8.3 % of the samples were found to be contaminated with the enteric viruses. The concentrations of the 12 chemical contaminants were found to be largely within the WHO suggested limits. Most of the chemical contaminants were not related to the detection rates of the viruses from the statistical analysis. However, some positive and negative associations between the viral genome's detection and the chemical concentrations were established for only three metals (Fe, Pb, Cd) and the PO4³⁻ Radical. Cd had a weak positive significant relationship with HAdV (rho = 0.146, p = 0.032) while Pb and Fe had a weak positive significant relationship with HEV genome detection (rho = 0.156, p = 0.022) and (rho = 0.148 and p = 0.029) respectively. There was a modest negative relationship between phosphate ions and HEV (rho = −0.174, p = 0.010). The results of our study do not provide support for the hypothesis of an association between the presence of human enteric viruses and the levels of twelve chemical contaminants.

Does Tap Water Quality Compromise the Production of Aedes Mosquitoes in Genetic Control Projects?

Simple Summary

Scientists all over the world are continually rearing and producing insects in laboratories for many purposes including pest control programmes. Aedes aegypti and Ae. albopictus are mosquitoes of public health importance due to their ability to vector human and animal pathogens and thus vector control represents an important component of many disease control programmes. Water is a factor of great importance in the larval environment of mosquito species. However, obtaining sufficient water of reliable quality for mosquito rearing is still challenging, especially in developing and least developed countries, where access even to clean drinking water is limited. In prospect of cost-effective methods for improved mass-rearing toward SIT application, we assessed the impact of using tap water on the development and quality of Aedes mosquitoes. Results showed that, tap water with hardness/electrical conductivity beyond certain levels (140 mg/l CaCO₃ or 368 µS/cm) was shown to have a negative impact on the production of Ae. albopictus and Ae. aegypti mosquitoes. These results suggest that the quality of water should be checked when using for rearing mosquitoes for release purposes in order to optimize the production performance of mass-rearing facilities. This may have important implications for the implementation of the sterile insect technique in areas where reverse osmosis water is a scarce or costly resource.

Abstract

A mosquito’s life cycle includes an aquatic phase. Water quality is therefore an important determinant of whether or not the female mosquitoes will lay their eggs and the resulting immature stages will survive and successfully complete their development to the adult stage. In response to variations in laboratory rearing outputs, there is a need to investigate the effect of tap water (TW) (in relation to water hardness and electrical conductivity) on mosquito development, productivity and resulting adult quality. In this study, we compared the respective responses of Aedes aegypti and Ae. albopictus to different water hardness/electrical conductivity. First-instar larvae were reared in either 100% water purified through reverse osmosis (ROW) (low water hardness/electrical conductivity), 100% TW (high water hardness/electrical conductivity) or a 80:20, 50:50, 20:80 mix of ROW and TW. The immature development time, pupation rate, adult emergence, body size, and longevity were determined. Overall, TW (with higher hardness and electrical conductivity) was associated with increased time to pupation, decreased pupal production, female body size in both species and longevity in Ae. albopictus only. However, Ae. albopictus was more sensitive to high water hardness/EC than Ae. aegypti. Moreover, in all water hardness/electrical conductivity levels tested, Ae. aegypti developed faster than Ae. albopictus. Conversely, Ae. albopictus adults survived longer than Ae. aegypti. These results imply that water with hardness of more than 140 mg/l CaCO₃ or electrical conductivity more than 368 µS/cm cannot be recommended for the optimal rearing of Aedes mosquitoes and highlight the need to consider the level of water hardness/electrical conductivity when rearing Aedes mosquitoes for release purposes.

Physicochemical Quality of Water from Chuho Springs, Kisoro District, Uganda

In the current study, water from Chuho springs used as the main water source in Kisoro municipality, Uganda were assessed for their suitability as drinking water. The temperature, turbidity, conductivity, total dissolved solids, dissolved oxygen, biological oxygen demand, total hardness, total alkalinity, calcium, magnesium, phosphates, iron, copper, arsenic, chlorides and the fluoride content of the water samples were determined. Not all the parameters met World Health Organizations’ guidelines for drinking water. Temperature, dissolved oxygen and fluorides were outside the recommended limits of 15 ℃, 10-12 mg/L and 1.5 mg/L, respectively. Further studies should assess the microbiological and sanitary profile of the springs.

Drinking Water Quality Mapping Using Water Quality Index and Geospatial Analysis in Primary Schools of Pakistan

Primary school children in the developing world often lack potable water, which may result in a high burden of water-related diseases and poor school performance. The present study aimed to characterize the drinking water quality in primary schools of Pakistan. We used a multistage random-sampling method to select 425 primary schools from selected districts of Sindh province. Standard methods were used to characterize water quality. The results were compared with maximum acceptable values recommended by the Pakistani National Environmental Quality Standards (Pak NEQS) and the World Health Organization (WHO) drinking water quality standards. Groundwater (62%) and surface water (38%) were identified as two major drinking water sources in the selected schools with varying levels of water quality. Among all parameters, dissolved oxygen (DO), pH, and nitrate remained within WHO and Pak NEQS water quality standard limit, while total dissolved solids (TDS) (33%), electrical conductivity (EC) (46%), chloride (34%), turbidity (27%), and hardness (11%) samples exceeded standard limits. All dissolved salts had moderate to strong positive correlations with TDS and EC values. Based on a water quality index (WQI), 74% of primary schools had access to excellent or good quality drinking water compared to 26% of schools that had access to either poor, very poor or unsuitable drinking water. Among all three regions, more schools from South Sindh had either poor, very poor or unsuitable drinking water (33%) compared to the Central (25%) and North zones (15%). Hence, water from these locations is unfit for human consumption and these schools need better water quality management plans to stop the spread of water-related diseases in primary school children.

Occurrence of Antibiotic-Resistant Bacteria and Genes in Two Drinking Water Treatment and Distribution Systems in the North-West Province of South Africa

With the increasing spread of antimicrobial resistance, there is growing attention to the contribution made by drinking water systems. The potential health impact of two drinking water treatment and distribution systems (A and B) in the North-West Province of South Africa was determined by investigating the water quality and occurrence of antimicrobial-resistant heterotrophic bacteria and genes in the raw and treated water over four seasons. Most of the physicochemical parameters except for electrical conductivity were within permissible limits. Coliform bacteria reduced from raw to potable water except for counts higher than the threshold recorded in Summer and Winter. A total of 203 heterotrophic bacterial isolates were recovered on chromogenic R2A medium and subjected to susceptibility testing to twelve antibiotics. Most of the isolates were resistant to β-lactam antibiotics and Trimethoprim, whereas they were susceptible to Ciprofloxacin, Erythromycin, and Neomycin. The proportions of Cephalothin and Kanamycin-resistant isolates were significantly higher (p < 0.05) after treatment for site A, compared to significantly lower β-lactam, Oxytetracycline, and Trimethoprim-resistant isolates for B. Over 50% of isolates were of high risk, indicating their origin from high antibiotic-use sources. Seventy-one (35%) isolates were multidrug-resistant, out of which the majority (53.5%, n = 38) possessed the strA gene, followed by strB 21 (29.6%), dfrB 13 (18.3%), aadA 11 (15.5%), bla_CTX-M 5 (7.0%), and tetA 3 (4.2%). The 16S rRNA gene sequences of the isolates revealed strains belonging to eight bacterial families, some of which are clinically important.

Assessment of GO/ZnO nanocomposite for solar-assisted photocatalytic degradation of industrial dye and textile effluent

An ecofriendly and solar light-responsive graphene oxide wrapped zinc oxide nanohybrid has been synthesized hydrothermally using lemon and honey respectively as chelating and complexing agents. By tuning the reaction conditions, a heterostructure between GO and ZnO has been formed during synthesis. The photocatalytic activity of the synthesized nanohybrid was investigated by degradation of hazardous organic textile dye (methylene blue) as well as wastewater under natural solar light. The nanohybrid exhibited excellent photocatalytic activity towards degradation (~ 89%) of methylene blue (MeB). Furthermore, along with decolorization, 71% of mineralization was also achieved. Interestingly, the nanohybrid has been found to be reusable up to 4 cycles without significant loss of photocatalytic activity. Along with this, the physicochemical parameters of the wastewater generated from textile industry have been also monitored before and after exposure to nanohybrid. The results revealed significant reduction in chemical oxygen demand (COD) (96.33%), biochemical oxygen demand (BOD) (96.23%), and total dissolved solids (TDS) (20.85%), suggesting its potential applicability in textile wastewater treatment.

Assessing land use and landscape factors as determinants of water quality trends in Nyong River basin, Cameroon

Changes in LULC and landscape factors impact water quality at spatial and temporal scales. In this study, we investigated the current status in water quality for sub-watersheds of the southern portion of the Nyong River basin of Cameroon from 1994 to 2014 using the WHO guideline. The trends in the water quality parameters were explored using Mann-Kendall test, and their relationship with changes in LULC and landscape factors were analysed using multiple linear regression and Pearson correlation. The current status in water quality did not exceed the WHO guideline limits for drinking water despite a 16% decrease in forest cover and 10% increase in agricultural areas during the period of record. The concentration and changes in water quality trends varied significantly among the sub-watersheds. The concentration of Ca²⁺, Mg²⁺, Na⁺, SiO_2, K⁺, DOC, SPM and WT showed significantly increasing trends in the Nsimi small sub-watershed, while only Ca²⁺, Mg²⁺, Na⁺ and NO₃^- showed significantly increasing trends in the large sub-watersheds of Mbalmayo and Olama. A combination of one to five LULC and landscape factors, including changes in urban cover, young secondary forest, slope, elevation and population explained 10 to 70% of the changes in water quality trends at watershed scale. Although the interaction of LULC and landscape factors seems to have low impact on the water quality so far, maintaining greater than 70% forest cover and appropriate fallow farming system is invaluable to protecting water quality in the Nyong River basin in the Congo basin and in other forest-rich regions.

Integrated Electrochemical Biosensors for Detection of Waterborne Pathogens in Low-Resource Settings

More than 783 million people worldwide are currently without access to clean and safe water. Approximately 1 in 5 cases of mortality due to waterborne diseases involve children, and over 1.5 million cases of waterborne disease occur every year. In the developing world, this makes waterborne diseases the second highest cause of mortality. Such cases of waterborne disease are thought to be caused by poor sanitation, water infrastructure, public knowledge, and lack of suitable water monitoring systems. Conventional laboratory-based techniques are inadequate for effective on-site water quality monitoring purposes. This is due to their need for excessive equipment, operational complexity, lack of affordability, and long sample collection to data analysis times. In this review, we discuss the conventional techniques used in modern-day water quality testing. We discuss the future challenges of water quality testing in the developing world and how conventional techniques fall short of these challenges. Finally, we discuss the development of electrochemical biosensors and current research on the integration of these devices with microfluidic components to develop truly integrated, portable, simple to use and cost-effective devices for use by local environmental agencies, NGOs, and local communities in low-resource settings.

Coupled Oxides/LLDPE Composites for Textile Effluent Treatment: Effect of Neem and PVA Stabilization

The polyvinyl alcohol (PVA) and neem extract were grafted onto coupled oxides (3ZT-CO) via reflux process to stabilize the particles to form 3ZT-CO/PVA and 3ZT-CO/Neem. These were then incorporated into LLDPE by melt blending process to give LLDPE/3ZT-CO/PVA and LLDPE/3ZT-CO/Neem composites. The Neem and PVA stabilized particles showed high zeta potential and dispersed homogeneously in water. The stabilization process altered the shape of the particles due to plane growth along the (002) polar direction. The stabilizers acted as capping agents and initiated the one-dimensional growth. The alkyl chain groups from PVA increased the polarity of the LLDPE/3ZT-CO/PVA and played a dominant role in the water adsorption process to activate the photocatalytic activity. This was further enhanced by the homogeneous distribution of the particles and low degree of crystallinity (20.87%) of the LLDPE composites. LLDPE/3ZT-CO/PVA exhibited the highest photodegradation (93.95%), which was better than the non-stabilized particles. Therefore, the photocatalytic activity of a polymer composite can be enhanced by grafting PVA and neem onto couple oxides. The LLDPE/3ZT-CO/PVA composite was further used to treat textile effluent. The results showed the composite was able to remove dye color by 93.95% and to reduce biochemical oxygen demand (BOD) and chemical oxygen demand (COD) by 99.99%.

The Efficacy of Treated Water from Water Filtration Machines for Safe Drinking Water Supply in Bandar Baru Bangi and Kajang, Selangor

This study was conducted to determine the physicochemical properties, microbiological quality, level of consumption, and effects of treated water from paid water filtration machines on health of the residents of Bandar Baru Bangi and Kajang, Selangor. The number of water samples taken for this study was 15 from the paid water filtration machines studied. The physicochemical assessment such as determination of pH, turbidity, total dissolved solids, conductivity, and dissolved oxygen was conducted, while the inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the mineral content of the treated water. The microbiological quality was determined using the pour plate method for colony count (22°C incubation for 72 hours and 37°C for 24 hours), while for coliforms and Escherichia coli, the membrane filtration method was utilized. The samples of treated water from the paid water filters were based on triplicate sampling (n = 3). The pH, turbidity, total dissolved solid values, and heavy metal concentration were within the safe level according to the Malaysian National Standard for Drinking Water Quality, Ministry of Health (MOH). The overall range for the pH values of the treated water samples was between 6.50 and 7.15, where this was within the recommended range. The total dissolved solids showed that all the treated water samples were in the range of the recommended standard (27 to 92 mg/L). The range of turbidity values for all the treated water samples was from 1.7 to 6 NTU, and the dissolved oxygen range was from 7.7 to 8.2 mg/L. The colony count results showed that most of the water samples complied with the standards of <4 log cfu/mL at 37°C and <3 log cfu/mL at 22°C of incubation temperatures. However, there was the presence of coliforms in four (4/15) of the treated water samples being at more than 4 cfu/100 mL, while E. coli was absent in all of the treated water samples. The overall results showed that all samples were safe to drink according to the Industrial Guide to Good Hygiene Practice by Automatic Vending Association of Britain (2000) and Food Act (1983) except for the four treated water samples (C, D, H, and I). For that reason, the filtered waters require quality evaluation and management, while the filters need to be replaced according to their designated schedule in order to ascertain that the drinking water is safe to be consumed by the public.

Rainwater as a Source of Drinking Water: Health Impacts and Rainwater Treatment

Rainwater is the main source of drinking water in tropical communities, especially in West Kalimantan. Air contamination causes rainwater to become acidic and cloudy and adds heavy metals such as Pb into rainwater. In addition to pollution, the way in which the rainwater is collected such as through zinc roofing also exposes the rainwater to heavy metals. The presence of Pb in rainwater will have an impact on the health of the community in the long run. The model of simple water treatment using filtration is needed to overcome this problem with the use of media available in the region. The media used are in the form of mollusk sand and activated carbon. In the end, the mollusk sand filtration model and activated carbon sorption were effectively used to filter polluted rainwater to be safe for consumption.

Mie scattering and microparticle-based characterization of heavy metal ions and classification by statistical inference methods

A straightforward method for classifying heavy metal ions in water is proposed using statistical classification and clustering techniques from non-specific microparticle scattering data. A set of carboxylated polystyrene microparticles of sizes 0.91, 0.75 and 0.40 µm was mixed with the solutions of nine heavy metal ions and two control cations, and scattering measurements were collected at two angles optimized for scattering from non-aggregated and aggregated particles. Classification of these observations was conducted and compared among several machine learning techniques, including linear discriminant analysis, support vector machine analysis, K-means clustering and K-medians clustering. This study found the highest classification accuracy using the linear discriminant and support vector machine analysis, each reporting high classification rates for heavy metal ions with respect to the model. This may be attributed to moderate correlation between detection angle and particle size. These classification models provide reasonable discrimination between most ion species, with the highest distinction seen for Pb(II), Cd(II), Ni(II) and Co(II), followed by Fe(II) and Fe(III), potentially due to its known sorption with carboxyl groups. The support vector machine analysis was also applied to three different mixture solutions representing leaching from pipes and mine tailings, and showed good correlation with single-species data, specifically with Pb(II) and Ni(II). With more expansive training data and further processing, this method shows promise for low-cost and portable heavy metal identification and sensing.

Geostatistical Distribution and Contamination Status of Heavy Metals in the Sediment of Perak River, Malaysia

Heavy metal pollution is one of the major environmental issues in recent decades owing to the rapid increase in urbanisation and industrialisation. Sediments usually act as sinks for heavy metals due to their complex physical and chemical adsorption mechanisms. In this study, heavy metals like lead (Pb), Zinc (Zn), Cadmium (Cd), Copper (Cu) and Iron (Fe) in the surface sediment from 15 location (upstream and downstream) on the Perak River, Malaysia were investigated by means of inductively coupled plasma optical emission spectroscopy (ICP-OES). The geostatistical prediction map showed the range of Pb, Zn, Cd, Cu and Fe concentration in upstream area was 14.56–27.0 µg/g, 20–51.27 µg/g, 1.51–3.0 µg/g, 6.6–19.12 µg/g and 20.24–56.58%, respectively, and in downstream areas was 27.6–60.76 µg/g, 49.04–160.5 µg/g, 2.77–4.02 µg/g, 9.82–59.99 µg/g and 31.34–39.5%, respectively. Based on the enrichment factor and geoaccumulation index, Cd was found to be the most dominant pollutant in the study area. Pollution load index, sediment quality guidelines and sediment environmental toxicity quotient data showed that the downstream sediment was more polluted than the upstream sediment in the Perak River. The multivariate analysis showed that Pb, Zn and Cu mainly originated from natural sources with minor contribution from human activities, whereas Fe and Cd originated from various industrial and agricultural activities along the studied area.

Salting-out assisted liquid-liquid extraction for the determination of ciprofloxacin residues in water samples by high performance liquid chromatography-diode array detector

Background

The occurrence of emerging pollutants like pharmaceuticals and related compounds in the aquatic and terrestrial environments is of increasing concern. Ciprofloxacin is one of the pharmaceuticals which is active against a wide range of bacteria. The main objective of this research is to develop a simple method for the extraction and determination of ciprofloxacin residues in environmental water samples.

Results

A salting-out assisted liquid-liquid extraction (SALLE) method for the determination of ciprofloxacin in water samples by high-performance liquid chromatography with diode array detector (HPLC-DAD) was developed. The calibration curve was linear over the range of 0.1-100 μg/L with coefficient of determination (r²) of 0.9976. The limits of detection (LOD) and quantification (LOQ) of the method were 0.075 and 0.25 µg/L, respectively. The reproducibility in terms of relative standard deviation (% RSD) was less than 10%. The applicability of the developed method was investigated by analyzing tap water, bottled mineral water and waste water and demonstrated satisfactory recoveries in the ranges of 86.4-120%.

Conclusion

The method offered a number of features including wide linear range, good recovery, short analysis time, simple operation process and environmental friendly. The developed method can be utilized as an attractive alternative for the determination of ciprofloxacin residues in environmental water matrices.

High Content of Lead Is Associated with the Softness of Drinking Water and Raised Cardiovascular Morbidity: A Review

Daily ingestion of lead (Pb), even through piped drinking water, has long time been an important issue of concern, attracting for decades research in environmental science and toxicology, and again comes to prominence because of recent high-profile cases of exposure of populations in several countries to Pb-contaminated water. Numerous studies have reported an association between Pb in water and the risk of cardiovascular pathologies. Low levels of magnesium and calcium, i.e., low degree of hardness of the drinking water, may accentuate Pb leaching from water pipes and furthermore increase Pb absorption. This review evaluates the evidence for an association between Pb exposure from drinking water and cardiovascular end points in human populations.

Phthalate and Metal Concentrations in Drinking Water in Lagos, Nigeria

INTRODUCTION

There have been no studies, monitoring programs, or data about phthalate levels made available to the public on the safety of residential drinking water in Lagos, Nigeria.

OBJECTIVES

The present study aimed to assess the concentrations of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), and zinc (Zn), lead (Pb), chromium (Cr), and cadmium (Cd) in drinking water drawn from taps in three residential areas of the state.

METHODS

High performance liquid chromatography and atomic absorption spectroscopy were used to determine the concentrations of phthalates and metals, respectively.

RESULTS

All of the water samples collected throughout the sampling period contained DMP, while DEP and DBP were present in only some of the samples. The highest mean DMP, DEP, and DBP concentrations of 1.15±0.28 mg/l, 0.09±0.16 mg/l, and 0.28±0.33 mg/l, respectively, were found in water samples collected from Lagos Street (Ebute-metta East). In addition, the trace/toxic metal concentrations in the water samples were found to be low for Cr, but high for Cd, Pb, and Zn, especially when compared with World Health Organization (WHO) limit values for drinking water. Lead recorded the highest mean concentration of 0.087±0.021 mg/l in the water samples obtained from Apapa Road (Ebute-Metta West). In the same vein, the highest significant (P < 0.01) mean Cr concentration of 0.047±0.012 mg/l was found in the water samples obtained from Apapa Road (Ebute-Metta West).

CONCLUSIONS

In view of the high concentrations of phthalates and metals in the water sampled in this study, and the potential adverse health effects of these contaminants, especially on children and women of child-bearing age, the Lagos State Government of Nigeria and the state water corporation are called upon to immediately institute a monitoring program to identify the sources of contaminants and take appropriate intervention measures.

COMPETING INTERESTS

The authors declare no competing financial interests.

Resource recovery of food waste through continuous thermophilic in-vessel composting

In the Kingdom of Saudi Arabia (KSA) and Gulf region, a very small amount of municipal solid waste (MSW) is treated for compost production. The produced compost through traditional methods of compost piles and trenches does not coincide with the international standards of compost quality. Therefore, in this study, a continuous thermophilic composting (CTC) method is introduced as a novel and efficient technique for treating food waste into a quality compost in a short period of time. The quality of the compost was examined by degradation rates of organic matter (OM), changes in total carbon (TC), ash contents, pH, dynamics in ammonium nitrogen (NH₄-N) and nitrate nitrogen (NO₃-N), and nitrification index (NI). The results showed that thermophilic treatment at 60 °C increased the pH of the substrate and promoted degradation and mineralization process. After 30 days of composting, the degree of OM degradation was increased by 43.26 and 19.66%, NH₄-N by 65.22 and 25.23%, and NO₃-N by 44.76 and 40.05% as compared to runs treated at 25 and 40 °C, respectively. The stability of the compost was attained after 30 to 45 days with quality better than the compost that was stabilized after 60 days of the experiment under mesophilic treatment (25 °C). The final compost also showed stability at room temperature, confirming the rapid degradation and maturation of food waste after thermophilic treatment. Moreover, the quality of produced compost is in line with the compost quality standard of United States (US), California, Germany, and Austria. Hence, CTC can be implemented as a novel method for rapid decomposition of food waste into a stable organic fertilizer in the given hot climatic conditions of KSA and other Gulf countries with a total net saving of around US $70.72 million per year.

Application of cell-based assays for toxicity characterization of complex wastewater matrices: Possible applications in wastewater recycle and reuse

Exposure to pre-concentrated inlet or outlet STP wastewater extracts at different concentrations (0.001% to 1%) induced dose-dependent toxicity in MCF-7 cells, whereas drinking water extracts did not induce cytotoxicity in cells treated. GC-MS analysis revealed the occurrence of xenobiotic compounds (Benzene, Phthalate, etc.) in inlet/outlet wastewater extracts. Cells exposed to inlet/outlet extract showed elevated levels of reactive oxygen species (ROS: inlet: 186.58%, p<0.05, outlet, 147.8%, p<0.01) and loss of mitochondrial membrane potential (Δψm: inlet, 74.91%, p<0.01; outlet, 86.70%, p<0.05) compared to the control. These concentrations induced DNA damage (Tail length: inlet: 34.4%, p<0.05, outlet, 26.7%, p<0.05) in treated cells compared to the control (Tail length: 7.5%). Cell cycle analysis displayed drastic reduction in the G1 phase in treated cells (inlet, G1:45.0%; outlet, G1:58.3%) compared to the control (G1:67.3%). Treated cells showed 45.18% and 28.0% apoptosis compared to the control (1.2%). Drinking water extracts did not show any significant alterations with respect to ROS, Δψm, DNA damage, cell cycle and apoptosis compared to the control. Genes involved in cell cycle and apoptosis were found to be differentially expressed in cells exposed to inlet/outlet extracts. Herein, we propose cell-based toxicity assays to evaluate the efficacies of wastewater treatment and recycling processes.

An ultrasound-assisted procedure for fast screening of mobile fractions of Cd, Pb and Ni in soil. Insight into method optimization and validation

A fast ultrasound-assisted sequential extraction (UASE) procedure for the determination of cadmium, lead and nickel fractions in soil was developed and fully validated. The working parameters of an ultrasound probe were optimized by comparing the content of metals in soil extracts obtained by the UASE procedure with that obtained by the conventional (with the aid of a vertical rotor) modified Community Bureau of Reference (BCR) procedure. The content of metals in soil fractions was determined by electrothermal atomic absorption spectrometry. The total time of extraction of metals from soil was shorten from 48 h to 27 min (total sonication time). The trueness of the developed method was confirmed by analysis of the certified reference material BCR-701. In order to indicate critical points of the developed UASE method, uncertainties of fractionation results were calculated and compared with those calculated for conventional modified BCR procedure. The method usefulness was tested for the determination of metal fractions in different types of soil collected in the Podlasie Province (Poland). The proposed procedure could be used for fast screening of mobile fractions of several heavy metals in soil.

Influence of temperature and reaction time on the conversion of polystyrene waste to pyrolysis liquid oil

This paper aims to investigate the effect of temperature and reaction time on the yield and quality of liquid oil produced from a pyrolysis process. Polystyrene (PS) type plastic waste was used as a feedstock in a small pilot scale batch pyrolysis reactor. At 400°C with a reaction time of 75min, the gas yield was 8% by mass, the char yield was 16% by mass, while the liquid oil yield was 76% by mass. Raising the temperature to 450°C increased the gas production to 13% by mass, reduced the char production to 6.2% and increased the liquid oil yield to 80.8% by mass. The optimum temperature and reaction time was found to be 450°C and 75min. The liquid oil at optimum conditions had a dynamic viscosity of 1.77mPas, kinematic viscosity of 1.92cSt, a density of 0.92g/cm³, a pour point of -60°C, a freezing point of -64°C, a flash point of 30.2°C and a high heating value (HHV) of 41.6MJ/kg this is similar to conventional diesel. The gas chromatography with mass spectrophotometry (GC-MS) analysis showed that liquid oil contains mainly styrene (48%), toluene (26%) and ethyl-benzene (21%) compounds.