Specific Water Sources Research Articles

Mapping and Assessing the Ecological Status of Water Sources in Mbarali River Sub catchment

Mbarali river subcatchment (MRS) is an important waterway that faces ongoing degradation due to climate change, land use change and poor institutional management which affected river flows in both quantity and quality. This study presents the findings of the cross-sectional survey conducted to identify, map and assess the ecological status of water sources in MRS. The overall objectives of this study are to provide a general understanding on the number of water sources and their spatial distribution, level of human induced pressure that detrimentally affect the quality of water sources and to propose conservation strategies to be taken onboard at a specific water source to ensure its sustainability. Literature review, field survey and stakeholder consultation were used to accomplish this study. Ecological Management Classes (EMC) adopted from Sood (2017), were used to assess the ecological status of identified water sources. Results revealed that, there are about 200 water sources within MBUMTILU WUA. From identified water sources, only 35% were found to be in good quality and the remaining 65% were degraded from anthropogenic activities. The analysis discloses that, Bottom valley cultivation found to be the leading and deadliest threats to water source. Site specific nature-based interventions were suggested to each identified water source depending on the level of degradation.

The probability of detecting host-specific microbial source tracking markers in surface waters was strongly associated with method and season.

Fecal contamination of surface waters presents significant human health and environmental risks. While many methods for understanding fecal contamination cannot differentiate between human and animal sources, microbial source tracking (MST) marker methods are used to identify fecal sources. To understand how to best employ MST marker data for managing fecal contamination risks, the present study compiled previously collected MST marker data (N = 12,878 samples) from across North America; each sample in the data set had been tested for fecal contamination from one or more of five sources (avian, canine, human, ruminant, swine). Using these data, this study aimed to characterize associations between non-methodological and methodological factors and detection of host-specific MST markers and determine how methodological differences may complicate the interpretation of these associations between studies. Variance partitioning analysis was used to quantify the variance in host-specific MST marker detection attributable to non-methodological and methodological factors. Conditional forest and regression analysis were utilized to assess the association between detection and select non-methodological and methodological factors. Between 10% (canine) and 38% (human) of total variance was uniquely attributable to non-methodological factors for any of the fecal sources considered, while between 50% (human) and 84% (canine) of variance could not be attributed to either methodological or non-methodological factors. This highlights the need for standardization of methods for MST marker detection across studies but also suggests that other factors, beyond those non-methodological variables considered here, influenced variation in the likelihood of MST marker detection.IMPORTANCEThis study underscores complications associated with comparing findings from studies that used different methodologies to detect the same fecal targets and highlights the difficulties associated with using non-comparable data to generalize findings and develop science-based risk management plans. These findings highlight the need for standardization of sampling and laboratory methods across microbial source tracking marker studies. Our findings build on previous research to suggest that one-size-fits-all approaches to managing fecal hazards in surface waterways may not be appropriate; instead, strategies tailored to specific water sources and conditions at the time of water use may be more effective.

Prevalence and factors contributing to stunted growth in young children of Khordha district, Odisha: A cross-sectional study.

Stunting, indicating chronic malnutrition in children, remains a pressing concern globally, especially in low- and middle-income countries. India, despite substantial efforts, continues to grapple with high rates of stunting, impacting child development and health outcomes. Understanding the multifaceted factors contributing to stunting is crucial for targeted interventions and policy formulation. This descriptive cross-sectional study was conducted in Balipatana, Khordha district, Odisha, India among 400 children. A survey employing structured questionnaires and WHO Anthropometric guidelines for data collection was used. Statistical analyses including Chi-square tests and logistic regression models were used to uncover significant associations. The study revealed a stunting prevalence of 28% among children under five, with 7% severe and 21% moderate stunting. Regression analysis revealed key risk factors included low birth weight (1.5-2.5 kg), parental illiteracy, lower household income (Rs. 1000-15000), inadequate toilet facilities, and specific drinking water sources. The findings align with global concerns about stunting, emphasizing the complex interplay of socioeconomic and environmental factors. Interventions targeting parental education, household economic status, and improving sanitation and drinking water facilities are imperative. By addressing these factors, focused efforts can be made to reduce childhood stunting, ensuring a healthier future for the nation's children.

Detection of Free-Living Amoeba in a tertiary care hospital

This study aims to investigate the presence of Free-Living Amoebae (FLA), particularly Acanthamoeba spp., in diverse water systems and body fluids within a hospital. Water and body fluid samples were collected from various locations. Cultivation of FLA was performed using Non-Nutrient Agar (NNA) culture with Escherichia coli, and microscopic observations after staining. Microscopic observations revealed the presence of Acanthamoeba spp. in pre-dialysis tank water and dental flush water samples. The identification of Acanthamoeba in specific water sources underscores the importance of continuous monitoring and preventive strategies to mitigate potential health risks.

Late glacial through Early Holocene environments inferred using pollen from coprolites and sediments recovered from Paisley Caves, Oregon

AbstractThe Paisley Cave archeological site in the Northern Great Basin has provided a rich archaeological record from 13,000 to 6000 cal yr BP, including abundant mammalian coprolites preserved in a well-dated stratigraphy. Here we analyze and contrast pollen from within coprolites and pollen in associated sediments to examine vegetation history and assess whether coprolite pollen provides unique information with respect to the coprolite producer, such as the use of specific habitats, foods, or water sources. We found that the dissimilarity of pollen assemblages between coprolites and associated sediments was greater than the serial dissimilarity between stratigraphically adjacent samples within either group. Serial dissimilarity within types was not greater for coprolites than sediments, as would be expected if there were unique pollen signatures derived from the short period (1–2 days) represented by each coprolite. Compared with sediment pollen assemblages, the coprolites had higher abundances of lighter pollen types, and some individual samples were high in wetland taxa (especially Typha). Our results are consistent with coprolite pollen representing short time periods collected as a mammal moves on the landscape, whereas sediment pollen reflects longer time periods and more regional vegetation indicators.

Organizing memories for generalization in complementary learning systems

Memorization and generalization are complementary cognitive processes that jointly promote adaptive behavior. For example, animals should memorize safe routes to specific water sources and generalize from these memories to discover environmental features that predict new ones. These functions depend on systems consolidation mechanisms that construct neocortical memory traces from hippocampal precursors, but why systems consolidation only applies to a subset of hippocampal memories is unclear. Here we introduce a new neural network formalization of systems consolidation that reveals an overlooked tension—unregulated neocortical memory transfer can cause overfitting and harm generalization in an unpredictable world. We resolve this tension by postulating that memories only consolidate when it aids generalization. This framework accounts for partial hippocampal–cortical memory transfer and provides a normative principle for reconceptualizing numerous observations in the field. Generalization-optimized systems consolidation thus provides new insight into how adaptive behavior benefits from complementary learning systems specialized for memorization and generalization.

To analyze or to throw away? On the stability of excitation-emission matrices for different water systems

Fluorescence spectroscopy has numerous applications to characterize natural and human-influenced water bodies regarding dissolved organic matter (DOM) and contamination. Analyzing samples in a timely manner is crucial to gaining valid and reproducible excitation-emission matrices (EEM) but often difficult, specifically in transnational projects with long transport distances. In this study, eight samples of different water sources (tap water, differently polluted rivers, and wastewater treatment plant (WWTP) effluents) were stored under standardized conditions for 59 days and analyzed regularly. With this data set, the sample and fluorescence spectra stability was evaluated. Established analysis methods such as peak picking and fluorescence metrics were compared over time and benchmarked against dissolved organic carbon (DOC) and a maximal change of 10% in terms of their variability. Additional high-performance liquid chromatography (HPLC) data to identify single organic compounds provides insights into these DOM alterations and allows for conclusions about the underlying biological processes. Our results corroborate in a systematic way that the higher the organic or microbial load, the faster the sample must be processed. For all water sources, considerable changes were found between days zero and one, indicating a potential systematic bias between in-situ and laboratory measurements. The absolute signals of individual peaks vary substantially after only a few days. In contrast, relative metrics are robust for a much longer time. For specific metrics, when filtered and stored under cool and dark conditions, tap water may be stored for up to 59 days, non-polluted river water for up to 31–59 days, and WWTP effluents for up to 14–59 days. The storability thus depends both on the specific water source and the analytical plan. By systematizing our understanding of how the specific water source and DOM concentration determine the stability of samples during storage, these conclusions facilitate efforts to establish a standardized protocol.

Parthenope’s Embodiment of Victory and the Crowning of Acheloios as ‘Victor over Death’: A Reconsideration of the Reverse Motif Exhibited on Neapolitan Coinage

The nymphs are truly marvelous figures of antiquity, and utterly pervasive, too. In Larson’s work, she records the name of some 426 of them, many of which (like meliai, ash tree nymphs) denote a group of such figures. Numbers like these give us a clear quantitative indication of just how essential the nymphs are to Greek culture. They operate in a liminal function mediating between the human and divine; they are therapeutic, and communion with the nymphs was often sought after in antiquity; their femininity is alluring and yet they are wildly unpredictable; they are always fixed to a specific water source from which their powers derive; and, they tend to exist in many multiples, often maintaining a general anonymity. Perhaps most importantly of all, they function as auxiliaries in the process of metempsychosis and often accompany psychopomps in ancient art. It is primarily for these reasons, and because Acheloios is often referred to as their father, that, within the pages of POΤΑΜΙKOΝ, Dr. Sisci and I advocated a somewhat controversial —or at least seemingly counterintuitive—claim, namely, that the winged figure crowning Acheloios Sebethos on the coinage of Neapolis was not Nike, but rather a chthonic nymph. Here we loosely followed the works of Kurt Regling, Ettore Gabrici, Maria Caccamo Caltabiano, and Grazia Salamone, all of whom questioned the seemingly unequivocal identification of winged female figures on coinage from Magna Graecia and Sicily with Nike, and in doing so advocated for some form of polysemy, or the idea that multiple meanings are conjoined in the iconography and this type of syncretism would have been apparent to the ancient observer. Dr. Sisci and I went so far as to relabel many of these ‘Nike’ figures as winged, chthonic nymphs, doing away with the Nike dimension entirely, since an Acheloios-nymph pairing made more sense within the Acheloian cultic context.

Listeria monocytogenes in Irrigation Water: An Assessment of Outbreaks, Sources, Prevalence, and Persistence.

As more fresh fruits and vegetables are needed to meet the demands of a growing population, growers may need to start depending on more varied sources of water, including environmental, recycled, and reclaimed waters. Some of these sources might be susceptible to contamination with microbial pathogens, such as Listeria monocytogenes. Surveys have found this pathogen in water, soil, vegetation, and farm animal feces around the world. The frequency at which this pathogen is present in water sources is dependent on multiple factors, including the season, surrounding land use, presence of animals, and physicochemical water parameters. Understanding the survival duration of L. monocytogenes in specific water sources is important, but studies are limited concerning this environment and the impact of these highly variable factors. Understanding the pathogen’s ability to remain infectious is key to understanding how L. monocytogenes impacts produce outbreaks and, ultimately, consumers’ health.

Drinking Water Quality and Public Health in the Kathmandu Valley, Nepal: Coliform Bacteria, Chemical Contaminants, and Health Status of Consumers.

Residents of Nepal's Kathmandu Valley draw drinking water from tube wells, dug wells, and stone spouts, all of which have been reported to have serious water quality issues. In this study, we analyzed drinking water samples from 35 tube wells, dug wells, stone spouts, and municipal tap water for bacterial and chemical contaminants, including total and fecal coliform, aluminum, arsenic, barium, beryllium, boron, cadmium, cobalt, chromium, copper, fluoride, iron, mercury, manganese, molybdenum, nickel, lead, antimony, selenium, thallium, uranium, vanadium, and zinc. We also asked a sampling of households who used these specific water sources to rate the taste of their water, list any waterborne diseases they were aware of, and share basic health information about household members. This survey provided us with information from 146 households and 603 individuals. We found widespread bacterial contamination of water sources, with 94% of sources having detectable total or fecal coliform. Nepal Drinking Water Quality Standards and World Health Organization (WHO) Drinking-Water Guidelines or health-based values were exceeded for aluminum (max = 0.53 mg/L), arsenic (max = 0.071 mg/L), iron (max = 7.22 mg/L), and manganese (max = 3.229 mg/L). The distribution of water sources with high arsenic, iron, and manganese appeared to be associated with floodplain deposits. Mixed effects logistic regression models were used to examine the interactions between social factors and water contaminants and their effects on household members' health. Consumers of water sources with both high and low concentrations of manganese were less likely to have a positive attitude towards school than those whose water sources had moderate concentrations of manganese. Social factors, especially education, played a large role in predicting individual health outcomes. Household taste ratings of drinking water were not correlated with iron or manganese concentrations, suggesting that WHO's reliance on aesthetic criteria for these contaminants instead of formal drinking-water guidelines may not be sufficient to protect public health.

Correlation of Salmonella enterica and Listeria monocytogenes in Irrigation Water to Environmental Factors, Fecal Indicators, and Bacterial Communities.

Outbreaks of foodborne illnesses linked to fresh fruits and vegetables have been key drivers behind a wide breadth of research aiming to fill data gaps in our understanding of the total ecology of agricultural water sources such as ponds and wells and the relationship of this ecology to foodborne pathogens such as Salmonella enterica and Listeria monocytogenes. Both S. enterica and L. monocytogenes can persist in irrigation water and have been linked to produce contamination events. Data describing the abundance of these organisms in specific agricultural water sources are valuable to guide water treatment measures. Here, we profiled the culture independent water microbiota of four farm ponds and wells correlated with microbiological recovery of S. enterica (prevalence: pond, 19.4%; well, 3.3%), L. monocytogenes (pond, 27.1%; well, 4.2%) and fecal indicator testing. Correlation between abiotic factors, including water parameters (temperature, pH, conductivity, dissolved oxygen percentage, oxidation reduction potential, and turbidity) and weather (temperature and rainfall), and foodborne pathogens were also evaluated. Although abiotic factors did not correlate with recovery of S. enterica or L. monocytogenes (p > 0.05), fecal indicators were positively correlated with incidence of S. enterica in well water. Bacterial taxa such as Sphingomonadaceae and Hymenobacter were positively correlated with the prevalence and population of S. enterica, and recovery of L. monocytogenes was positively correlated with the abundance of Rhizobacter and Comamonadaceae (p < 0.03). These data will support evolving mitigation strategies to reduce the risk of produce contamination by foodborne pathogens through irrigation.

A δ18O and δ2H stable water isotope analysis of subalpine forest water sources under seasonal and hydrological stress in the Canadian Rocky Mountains

AbstractSubalpine forests are hydrologically important to the function and health of mountain basins. Identifying the specific water sources and the proportions used by subalpine forests is necessary to understand potential impacts to these forests under a changing climate. The recent “Two Water Worlds” hypothesis suggests that trees can favour tightly bound soil water instead of readily available free‐flowing soil water. Little is known about the specific sources of water used by subalpine trees Abies lasiocarpa (Subalpine fir) and Picea engelmannii (Engelmann spruce) in the Canadian Rocky Mountains. In this study, stable water isotope (δ18O and δ2H) samples were obtained from S. fir and Engelmann spruce trees at three points of the growing season in combination with water sources available at time of sampling (snow, vadose zone water, saturated zone water, precipitation). Using the Bayesian Mixing Model, MixSIAR, relative source water proportions were calculated. In the drought summer examined, there was a net loss of water via evapotranspiration from the system. Results highlighted the importance of tightly vadose zone, or bound soil water, to subalpine forests, providing insights of future health under sustained years of drought and net loss in summer growing seasons. This work builds upon concepts from the “Two Water Worlds” hypothesis, showing that subalpine trees can draw from different water sources depending on season and availability. In our case, water use was largely driven by a tension gradient within the soil allowing trees to utilize vadose zone water and saturated zone water at differing points of the growing season.

Essential elements and standards for their contents in drinking water

Certain essential and conditionally essential natural elements (selenium, chromium, iodine, molybdenum, cobalt, vanadium, fluorine, lithium, silicon, boron, and bromine) are standardized in terms of their contents in drinking water as per sanitary-toxicological parameters of adverse health effects. Our research goal was to determine a contribution made by drinking water into supplying a human body with essential natural elements as well as to substantiate the necessity to update standards regarding these substances. We applied calculation models for dose equivalents of essential elements MPC (maximum permissible concentration), MPC calculations for these substances basing on a necessary 20 % contribution made by drinking water into reference doses, and calculation of non-carcinogenic health risks due to essential elements occurrence in specific drinking water sources with these elements being distributed into different groups as per similar effects produced on certain organs and systems in a body. We took existing drinking water sources containing 6 essential elements with similar effects as an example and applied a procedure for assessing non-carcinogenic health risks. Acting nickel and selenium MPC do not supply a body with an optimal daily intake whereas their determined MPC are not only harmless but also conform to the minimum necessary intake dose. At the same time neither acting lithium MPC nor its calculated one taking into account risk assessment based on internationally accepted reference doses doesn’t provide the minimum necessary daily intake into a human body. When boron and vanadium are contained in drinking water in a concentration close to their MPC, then their 20 % contribution into the reference dose is exceeded (71.4 % and 164.7 % accordingly). Introduction of these essential elements with food can become a factor that determines non-carcinogenic risk level.

Эссенциальные элементы и их нормирование в питьевой воде

Certain essential and conditionally essential natural elements (selenium, chromium, iodine, molybdenum, cobalt, vanadium, fluorine, lithium, silicon, boron, and bromine) are standardized in terms of their contents in drinking water as per sanitary-toxicological parameters of adverse health effects. Our research goal was to determine a contribution made by drinking water into supplying a human body with essential natural elements as well as to substantiate the necessity to update standards regarding these substances. We applied calculation models for dose equivalents of essential elements MPC (maximum permissible concentration), MPC calculations for these substances basing on a necessary 20 % contribution made by drinking water into reference doses, and calculation of non-carcinogenic health risks due to essential elements occurrence in specific drinking water sources with these elements being distributed into different groups as per similar effects produced on certain organs and systems in a body. We took existing drinking water sources containing 6 essential elements with similar effects as an example and applied a procedure for assessing non-carcinogenic health risks. Acting nickel and selenium MPC do not supply a body with an optimal daily intake whereas their determined MPC are not only harmless but also conform to the minimum necessary intake dose. At the same time neither acting lithium MPC nor its calculated one taking into account risk assessment based on internationally accepted reference doses doesn’t provide the minimum necessary daily intake into a human body. When boron and vanadium are contained in drinking water in a concentration close to their MPC, then their 20 % contribution into the reference dose is exceeded (71.4 % and 164.7 % accordingly). Introduction of these essential elements with food can become a factor that determines non-carcinogenic risk level.

Water source utilization under differing surface flow regimes in the riparian species Liquidambar styraciflua, in the southern Appalachian foothills, USA

Studies across the United States and globally have revealed that mature riparian trees often utilize little streamwater, relying on soil moisture and groundwater instead. Contrastingly, riparian plants growing in wetland systems in the southeastern US use greater proportions of swamp water. The purpose of the present study was to determine if plant water uptake was linked to surface flow regime of the riparian system, characterized by stream flow and standing pond water nearby. Water sources of Liquidambar styraciflua growing along Whetstone Creek, a perennial stream in Stoneville, NC, were determined and compared to those of individuals growing along adjacent spring-fed ponds by analyzing stable isotopic compositions of plant water. Plant water status and environmental variables were also monitored due to possible influences on the specific water sources accessed. It was expected that pondside individuals, due to the lower flow rate and increased pond water availability, would utilize a greater amount of surface water than groundwater, which is shallow at the site, compared to streamside trees. However, trees at both sites appeared to rely about equally on shallow soil and surface water, while groundwater contributed only a minor proportion to trees at both sites. There were no meaningful relationships between the water sources measured and environmental factors, and plant water status was consistently high for trees at both sites. The current study is one of the first to demonstrate quantitatively a strong reliance on surface water by mature riparian trees in the southeastern US.

Potentialities of Membrane Water Treatment for Removing Organic Pollutants from Natural Water

The potentialities of using ultrafiltration, nanofiltration, and reverse-osmosis membranes for removing organic compounds from water are considered. Experimental results obtained by the authors and the information taken from the literature characterizing the interaction between membranes and organic compounds contained in natural water are presented. Data are obtained concerning the efficiency of different membrane technologies in the removal of organic compounds from natural water. The growth rate of the deposits of organic substances having different molecular weight has been studied. The effect of the membrane’s material and the hydrodynamic mode of the membrane’s operation on the formation rate of organic deposits has been demonstrated. The influence of these substances’ nature, their concentration in natural water, and the molecular weight thereof on the deposition rate on membranes have been revealed. In the experiments, tap water taken from the Moscow water supply and river water were used. The results of the authors’ experiments and the results obtained by other Russian and foreign researchers presented in the paper make it possible to consider ultrafiltration as a reliable way to retain organic macromolecules as well as finely dispersed and colloidal impurities. With retaining low-molecular organic compounds that determine the color of water, ultrafiltration is restricted. In the synthesis of nanofiltration membranes, films with different pore size and charge are used. Therefore, for a specific water source and water consumer, an individual choice of nanofiltration membranes is required, a wide range of which is available in the market. Nanofiltration membranes of the NE-90 and NE-70 types for surface waters having a color of 20–100 degrees provide a 85 and 75% decrease in the oxidability level, respectively. According to the results of studies concerning the efficiency of artesian water purification, domestic OPMN-K nanofiltration membranes can also profoundly purify water from natural organic compounds. Among all the membranes used in the water treatment technology, reverse-osmosis membranes have the smallest pore size; their use provides retaining organic compounds with a molecular weight lower than 100 Da. The studies have shown that reverse-osmosis membranes exhibit a 99.5% retention level for the compounds with a molecular weight of 150 Da and a 99.9% retention level for the compounds with a molecular weight higher than 1000 Da. To reveal the nature and concentration of organic compounds deposited on the membranes, water spectrograms have been used.

Plasmonic silver/silver oxide nanoparticles anchored bismuth vanadate as a novel visible-light ternary photocatalyst for degrading pharmaceutical micropollutants

The degradation of pharmaceutical micropollutants is an intensifying environmental problem and synthesis of efficient photocatalysts for this purpose is one of the foremost challenges worldwide. Therefore, this study was conducted to develop novel plasmonic Ag/Ag2O/BiVO4 nanocomposite photocatalysts by simple precipitation and thermal decomposition methods, which could exhibit higher photocatalytic activity for mineralized pharmaceutical micropollutants. Among the different treatments, the best performance was observed for the Ag/Ag2O/BiVO4 nanocomposites (5 wt.%; 10 min's visible light irradiation) which exhibited 6.57 times higher photodegradation rate than the pure BiVO4. Further, the effects of different influencing factors on the photodegradation system of tetracycline hydrochloride (TC-HCl) were investigated and the feasibility for its practical application was explored through the specific light sources, water source and cycle experiments. The mechanistic study demonstrated that the photogenerated holes (h+), superoxide radicals (•O2−) and hydroxyl radicals (•OH) participated in TC-HCl removal process, which is different from the pure BiVO4 reaction system. Hence, the present work can provide a new approach for the formation of novel plasmonic photocatalysts with high photoactivity and can act as effective practical application for environmental remediation.

Strengths of correlations with formation of chlorination disinfection byproducts: effects of predictor type and other factors

Measurements of the UV-Vis absorbance (Abs) and intensity of fluorescence emission (Fluor), as well as of concentrations of total or dissolved organic carbon (OC) in aqueous samples are commonly used to estimate the potential for disinfection byproducts (DBPs) formation during water chlorination. In this work, based on 574 linear associations collected from 70 experimental research papers published over the period of 1997-2019, the strengths of the correlations of Abs, Fluor, and OC with DBPs concentrations are compared. The correlations were expressed as approximately normally distributed Z-scores using Fisher variance-stabilizing transformation. The effects of specific prediction method, chlorination agent, water source, and DBPs type, with consideration of possible effects due to the presence of bromide, are examined against Z-scores by ANOVA, testing main effects and some variables interactions. The performed analysis is a first attempt to expose differences and patterns in correlation strengths associated with DBPs formation, based on systematically covered broad existing literature. Abs and OC concentration of water samples tend to demonstrate the strongest correlations with DBPs formation as compared with specific UV absorbance (SUVA) or intensity of fluorescence emission. Correlations of DBPs formation during chloramination demonstrated weaker strengths as compared with other chlorination agents, suggesting more caution in predicting DBPs concentrations, based on simple descriptors such as Abs, OC, and Fluor. In a series of different water types, the correlations with DBPs formation are expected to be enhanced, when wastewater is chlorinated. Non-fluorescent matter may be an important contributor to DBPs formation during water chlorination. When fluorescence intensity is considered as a predicting tool, choosing humic-like rather than proteinaceous fluorescence may enhance the strengths of the correlations with DBPs formation. Different performances of Abs, OC, and Fluor in correlating with DBPs formation may be beneficial for their concurrent use helping to optimize removal of different DBPs precursors.

Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwater

Maize is the third important cereal crop after wheat and rice, especially in Egyptian villages. It is used in baking as a substitution component in wheat products and a main component in snacks for children. The target of this study was to estimate the risk assessment of lead (Pb) and cadmium (Cd) in maize grains cultivated in the agricultural soil irrigated by the contaminated water in comparison with that irrigated by freshwater. Lead (Pb) and cadmium (Cd) levels in irrigation water, soils and maize grains collected from different sites in Egypt were determined using ICP-OES. The studied samples were collected from 5 agricultural sites irrigated with freshwater (Nile River water and groundwater) as well as 4 agricultural sites irrigated with low-quality water (contaminated by sewage and industrial wastewater). Results exhibited that the levels of Pb and Cd in soil and maize grains were significantly affected by their levels in irrigation water; where, the levels of Pb and Cd in soil and maize grains irrigated by low-quality water possessed the multiple concentrations in comparison with those irrigated by freshwater. Specific water sources such as Kafr-Dokhmais and Al-Nasiria sites, Kafr El-Sheikh governorate had the highest levels of metals in the samples of irrigation water, soil and maize grains (p < 0.05). Metals levels in water and soil samples were within the permissible limits except Cd in low-quality water samples. Levels of Pb in maize grains irrigated by low-quality water were above the permissible limits (0.20 mg kg−1), while Cd levels were within the permissible limits (0.1 mg kg−1) except Al-Nasiria samples. Levels of Pb and Cd in maize grains irrigated by low-quality water were 19–30 folds those of maize grains irrigated by freshwater. The risk assessment of Pb and Cd levels in maize grains was estimated by daily intake of metals (DIM) and health risk index (HRI). All determined HRI was <1 indicating a non potential health risk for both adults and children.

Water characterization and early contamination detection in highly varying stochastic background water, based on Machine Learning methodology for processing real-time UV-Spectrophotometry

Water is a resource that affects every aspect of life. Intentional (terrorist or wartime events) or accidental water contamination events could have a tremendous impact on public health, behavior and morale. Quick detection of such events can mitigate their effects and reduce the potential damage. Continuous on-line monitoring is the first line of defense for reducing contamination associated damage. One of the available tools for such detection is the UV-absorbance spectrophotometry, where the absorbance spectra are compared against a set of normal and contaminated water fingerprints. However, as there are many factors at play that affect this comparison, it is an elusive and tedious task. Further, the comparison against a set of known fingerprints is futile when the water in the supply system are a mix, with varying proportions, of water from different sources, which differ significantly in their physicochemical characteristics. This study presents a new scheme for early detection of contamination events through UV absorbance under unknown routine conditions. The detection mechanism is based on a new affinity measure, Fitness, and a procedure similar to Gram based amplification, which result in a flexible mechanism to alert if a contamination is present. The method was shown to be most effective when applied to a set of comprehensive experiments, which examined the absorbance of various contaminants in drinking water in lab and real-life configurations. Four datasets, which contained real readings from either laboratory experiments or monitoring station of an operational water supply system were used. To extend the testbed even further, an artificial dataset, simulating a vast array of proportions between specific water sources is also presented. The results show, that for all datasets, high detection rates, while maintaining low levels of false alarms, were obtained by the algorithm.