Use Of Wastewater For Irrigation Research Articles

ENVIRONMENTALLY ACCEPTABLE NORMS OF MAN-MADE LOADS ON IRRIGATED LANDS DURING WASTEWATER DISPOSAL

Nature management in a broad sense is considered as a combination of various forms of exploitation of the natural resource potential of natural and natural-man-made systems and measures to preserve it. Its most important component is the preservation, reproduction and rational change of the ecological balance of natural systems. It is from these positions that it seems necessary to determine environmentally acceptable norms of man-made loads on irrigated lands during the disposal of wastewater, widely used in the practice of water supply and sanitation. The use of wastewater from industrial and municipal facilities for irrigation of land is of fundamental importance from both ecological and economic positions. From an ecological point of view, the use of wastewater for irrigation of agricultural crops, in the presence and creation of waste-free and safe technologies for their disposal in irrigation fields, can serve as the basis for rational nature management, since at the same time the ecological sustainability of landscapes is ensured, which in turn makes possible the long-term exploitation of natural resources without their pollution and degradation. From an economic point of view, by creating agricultural landscapes in unproductive lands, using wastewater from industrial and municipal facilities, it is possible to ensure the production of a certain amount of agricultural products, provided that the damage caused to the natural system (S) will be less than the profit (S). Under these conditions, the object of wastewater disposal is the soil, which requires the need to determine a number of environmentally effective ways to optimize the soil-forming process, which would create, in an agroecological and economic sense, a perfect technology for their disposal, taking into account the laws of nature.

Prospecting toxicity of the avobenzone sunscreen in plants.

Avobenzone (AVO) is a sunscreen with high global production and is constantly released into the environment. Incorporating sewage biosolids for fertilization purposes, the leaching from cultivated soils, and the use of wastewater for irrigation explain its presence in the soil. There is a lack of information about the impact of this sunscreen on plants. In the present study, the ecotoxicity of AVO was tested at concentrations 1, 10, 100, and 1,000ng/L. All concentrations caused a reduction in root growth of Allium cepa, Cucumis sativus, and Lycopersicum esculentum seeds, as well as a mitodepressive effect, changes in the mitotic spindle and a reduction in root growth of A. cepa bulbs. The cell cycle was disturbed because AVO disarmed the enzymatic defense system of root meristems, leading to an accumulation of hydroxyl radicals and superoxides, besides lipid peroxidation in cells. Therefore, AVO shows a high potential to cause damage to plants and can negatively affect agricultural production and the growth of non-cultivated plants.

Heavy metal contamination through wastewater irrigation on the soil and vegetables: Impact on the nutrient content and health risks ​

The use of wastewater irrigation may contribute to the metal accumulation, and reduction of nutrient level of vegetables, which would then have an adverse effect on human health. Therefore, in the present study we investigated heavy metals contamination and its impact on nutrient quality of vegetables and health risk. The study was conducted from the agricultural fields of Varanasi distinct during the period from March 2022 to June 2023 and all the laboratory work was carried in the department of Botany, Banaras Hindu University. Heavy metal concentrations in water, soil, and vegetable samples were measured using an atomic absorption spectrophotometer. The physiochemical property (pH), daily intake of metal, metal pollution index and health quotient were also calculated according to the published protocols. All heavy metal were found in higher concentrations in the wastewater irrigated soil that control site. The Lohta site had the highest concentration of heavy metals in the vegetables, followed by Dinapur, and least at control site (BHU). The highest concentration of metals (Cu, Zn, and Pb) were found in the leafy vegetables (S. oleracea and A. esculentus) whereas lowest in fruity vegetables (P. vulgaris). The rise in the Metal Pollution Index (MPI) also provided evidence for the greater metal content of these vegetables. The S. oleracea was found to have the highest DIM (0.061 g/g) while P. vulgaris had the lowest (0.007 g/g). HQ values of these metals were found greater than one ( greater than 1) for both children and adults on the ingestion of the vegetables of wastewater irrigated sites. Further, nutrient contents (Na, Mg, Ca) were also declined in the vegetables of wastewater irrigated site when compared to control site. These findings suggest that the consumption of such vegetables leads to compromised health and might be associated with severe health risk in the human.

Estimación de la disponibilidad a pagar en dos acuíferos en Baja California, México

This study presents an assessment of the perceptions and willingness-to-pay (WTP) of farmers using groundwater for irrigation in two aquifers in northern Baja California, Mexico. Contingent Valuation (CV) measured their WTP to ensure availability of groundwater in the future. Data from surveys of 70 and 54 farmers in the Maneadero and Guadalupe valleys, respectively, were combined and analyzed using logistic regression. Farmer WTP is influenced by variables reflecting “present water scarcity for agricultural use”, “education and family income levels”, “partial use of wastewater for irrigation”, “water quality”, and “payment amount”. A WTP estimate of $US 0.13/m3 suggests that the environmental cost of depleting aquifers over a 20-year span could reach $US 17.4-24.9 million for the Guadalupe aquifer and $US 20.50 million for the Maneadero aquifer. This information could serve as a starting point to help decision makers in northern Mexico design more environmentally sustainable pricing policies, including investing revenues in long-term aquifer restoration.

The use of wastewater for irrigation: Pros and cons for human health in developing countries

Intensive cultivation of vegetables and scarcity of clean irrigation water has resulted in the increased use of wastewater for irrigation worldwide, especially in developing countries. In this review, we analyze and outline the drawbacks of such practice to provide information on ecological and human health risk associated with the practice and suggested a way forward. For our review to reflect the best practice and technological advances in state-of-the-art terms, articles published in the last decade were considered. The review started by highlighting the growing concern of water scarcity in developing countries, the sources of wastewater, how farmers utilize the wastewater for irrigation, and limitations of existing studies. It then proceeds with in-depth look at the benefits of using wastewater for irrigation, recent diseases discovered due to wastewater irrigation, existing knowledge on the alteration of soil physical and chemical properties resulting from wastewater irrigation, heavy metals contamination of soil and food crops due to wastewater irrigation, risk assessment associated to wastewater irrigation, and then finally we proposed a novel approach of using wastewater for irrigation. In terms of benefits, more emphasis was focused on economic and environmental benefits, while also highlighting benefits to human health. We have also highlighted wastewater-borne diseases, paying more attention to recent ones that are of acute and chronic risks. In terms of the alteration of soil’s physical and chemical properties, more emphasis was put on its effects on soil fertility and productivity. The review critically revealed the heavy metals contaminating soil and food crops because of wastewater irrigation, and risk assessment also discoursed in detail. In the end, special consideration was given to the formulation of a novel approach to using wastewater for irrigation in a sustainable way, while avoiding or at least minimizing associated human health risk that are becoming rampant, especially in developing countries.

Evaluation of nickel toxicity and potential health implications of agriculturally diversely irrigated wheat crop varieties

Nickel (Ni) is essential for plant metabolism but is dangerous to most plants and other organisms when present in large concentrations. In this study, nickel (Ni) was chosen as an important environmental pollutant and toxic substance due to its widespread availability, and high persistence, causing soil pollution and serious environmental problems. The main aim of the study is to determine the Ni content in various wheat varieties and soil grown in various water regimes (sewage water, groundwater and industrial water) in Punjab, Pakistan. The Ni concentrations were determined via the ecological environment (water, soils) and below (roots) and above-ground plant organs (shoots and wheat grains) and phytostabilization potential assessment using various pollution indices. The results showed that the mean Ni concentration in different wheat varieties varied from 1.35 to 2.45 mg/kg, 1.17 to 2.42 mg/kg, 1.09 to 2.10 mg/kg and 0.99 to 1.54 mg/kg in soil, root, shoot, and grains, respectively. Research findings also revealed that the nickel concentration in soil and grains is within the safe limits and all the indices for Ni are less than 1. As a result, the studied wheat cultivars appear to be safe for consumption. However, it can be said that the continuous use of wastewater for irrigation may pose health risks for living things in the food chain.

Impact of urban wastewater reuse for irrigation on hydro-agro-ecological systems and human health risks: A case study from Musi river basin, South India

Use of wastewater for irrigation remains a disagreement among policymakers and researchers. However, it is fact that wastewater may contains many contaminants including heavy metals that can negatively impact ecosystem health. The present study is an attempt to assess the impact of wastewater use on soil, crop, and water and associated health risks based on exposure risk model where wastewater irrigation is more prominent in Hyderabad city, South India by analyzing physical (pH, EC, turbidity, oil and grease, TSS), chemical (Zn, Cr, Pb, Mn, Cu and Ni) and biological (BOD, COD, DO) parameters. The results indicated that biological contamination and the presence of heavy metals with the rising groundwater salinity. Low to moderate cancer risks are also inferred if humans are exposed to these waters for a long time. However, the study suggests continuous monitoring of the water and soil quality in wastewater irrigated areas to take remedial actions for sustainable agriculture development and protect ecosystems.

How agricultural practices affect the risk of human contamination by infectious pathogens: the need for a ‘One Health’ perspective

Abstract We conducted a comprehensive literature review with a global geographic scope, of interactions between agricultural crop production practices (excluding crop protection practices) and biological human health hazards. The majority of relevant references dealt with bacterial contaminations and infections, largely due to the important public health issue of antibiotic resistance. Indicator coliforms were particularly significant (only a minority mentioned harmful Escherichia coli strains), followed by species belonging to Salmonella , Campylobacter , Clostridia , Pseudomonas , and Listeria genera. Protozoan Cryptosporidium spp. and Giardia spp., and helminthic Ascaris spp. and Trichuris spp. dominated the references to parasites. Enteric viruses largely dominated the references to viruses (particularly noroviruses and rotaviruses). Very few references mentioned human fungal pathogens. Fresh vegetables were the most commonly mentioned crops, particularly leafy greens and those eaten raw, due to the use of wastewater for irrigation, and fertilization with livestock manure and human excreta/sewage sludge, potentially unsafe practices. While earlier literature reviews have shown that crop protection practices are central to the One Health concept, this review shows that other agricultural practices can also contribute to human and environmental health via different pathways, including better soil health, water quality, better food safety, and human nutrition. Our review underlines that besides tradeoffs, synergies should be sought, between, on the one hand, saving/preserving freshwater and organic waste recycling (affecting environmental health and some aspects of human health), and health hazards associated with the use of potentially contaminated waste on the other (affecting other aspects of human health), from both agroecological and One Health perspectives.

Investment priorities for research and innovation in urban agri-food systems: Toward more resilient cities in the Global South

Urban and peri-urban agriculture (UPA) is widely distributed throughout the Global South. Despite urban population growth and diversifying food habits, UPA delivers an important part of urban food supply, as well as other types of services to cities, such as employment and waste reuse. Nevertheless, the extent and importance of UPA varies between different urban areas, while challenges like limited recognition, land conversion, and water pollution and competition threaten the potential of UPA to contribute to urban resilience. Key investment priorities for research and innovation for overcoming current challenges include incentivized peri-urban zoning, urban allocation of productive lands, and increasing capacities for controlled environment agriculture (CEA). Innovative repositioning of food marketing can help to strengthen supply of healthy food from UPA production, increase decent employment, and turn food markets into nutrition hubs. Priority innovations for contributing to the circular bioeconomy of cities include scaling the safe use of wastewater for irrigation through investments in the adoption of multiple risk-barrier approaches and scaling UPA-based ecosystem services for valorising solid waste and environmental management. Innovations in urban governance are required to support these processes by bringing food systems into urban planning through food mapping and the multisectoral platforms for dialogue and policy formulation across city regions and with vertical levels of government.

Phytoremediating a Wastewater-Irrigated Soil Contaminated with Toxic Metals: Comparing the Efficacies of Different Crops

A formidable challenge in suburban agriculture is the sustainability of soil health following the use of wastewater for irrigation. The wastewater irrigation likely toxifies the crop plants making them unconsumable. We used a multivariate, completely randomized design in a greenhouse, comparing the phytoextraction capacities of Brassica juncea, Eruca sativa, Brassica rapa, and Brassica napus—all grown on silt loam soil irrigated with industrial wastewater, canal water, and a 1:1 mixture, during 2018. The studied Brassica plants were generally closely efficient in remediating toxic metals found in wastewater irrigated soil. Substantial differences between Brassica and Eruca plants/parts were recorded. For example, B. napus had significantly higher metal extraction or accumulation compared to E. sativa for Zn (71%), Cu (69%), Fe (78%), Mn (79%), Cd (101%), Cr (57%), Ni (92%). and Pb (49%). While the water and plant were the main predictors of metal extraction or accumulation, an interaction between the main effects substantially contributed to Cu, Mn, and Fe extractions from soil and accumulations in plants. Significant correlations between biological accumulation coefficient and biological transfer coefficient for many metals further supported the metal extraction or accumulation efficiencies as: B. napus > B. juncea > B. rapa > E. sativa. Root-stem mobility index correlation with stem-leaf mobility index indicated the metal translocation along the root-stem-leaf continuum. Therefore, we suggest that these crops may not be used for human or animal consumption when grown with industrial wastewater of toxic metal concentrations ≥ permissible limits. Rather these plants may serve as effective remediators of toxic metal-polluted soil.

BIOLOGICAL RISKS OF WASTE WATER FOR IRRIGATION

Increasing activities in the World, enhance the pressure on freshwater resources. The most important solution to reduce this pressure is the use of treated wastewater. The use of wastewater is becoming increasingly common on a global scale. Wastewater used irrigation, especially in agriculture and landscape areas. It can use some industrial activities such as cooling, washing, boiler feeding and fire extinguishing. Wastewater is generally used directly or by creating a wetland after physical pre-treatment. Changes in living standards have diversified wastewater contents. In recent years, domestic wastewater contains substances, which are extremely harmful to living health, that cannot be treated with physical processes, and require expensive and complex treatment techniques. Heavy metals, microorganisms and endocrine disruptors in wastewater pose serious health risks to life. In this study, biological risks in the use of wastewater in irrigation will be evaluated. In the study, the biological risks that the pathogenic microorganisms and endocrine disruptors contained in the wastewater may cause in irrigated areas and suggestions for their solution are given.

Determining Farmers’ Awareness About Climate Change Mitigation and Wastewater Irrigation: A Pathway Toward Green and Sustainable Development

The present study was conducted in one of the major agriculture areas to check farmers’ awareness of climate change, adaptation measurements, and use of wastewater for irrigation. A semi-structured questionnaire was adopted from the existing literature, it was divided into different parts such as demographic information, use of wastewater for irrigation, farmer’s livelihood assets, climate change deciding factors, and adaptation measures, and some statistical tools (correlation and regression) were used to analyze the data. The farmers with enough resources and assets regarded themselves as safer and have enough capacity to bear the negative impacts of climate change. Farmers’ assets (FA) with determinants of climate change (DCC) and adaption measures (AM) are highly significant with the correlation values of 0.440 and 0.466, respectively, and DCC with AM (0.269). The correlation values for other variables are: gender with cultivated land 0.202, wastewater use (WWU) 0.419, farmers’ assets (FA) 0.766, determinants of climate change (DCC) 0.381, and adaption measures (AM) 0.449. Floods and droughts variables have shown a significant relationship with adaption measures at p-value 0.000 and coefficient 0.176 and p-value 0.021 and coefficient 0.063, respectively. The study will aid in the implementation of effective monitoring and public policies to promote integrated and sustainable water development.

Soil contamination by microplastics in relation to local agricultural development as revealed by FTIR, ICP-MS and pyrolysis-GC/MS

Plastic film mulching and use of wastewaters for irrigation have been common agricultural practices for over half a century in Tunisia, especially in arid regions, resulting in the undesired creation of a pathway for microplastics (MPs) to enter farmland soil. In order to assess the extent and characteristics of soil contamination by MPs in the Moknine province, an area of intensive agricultural practices, 16 farmland soil samples were collected and characterized. The total concentration of targeted MPs was 50–880 items/kg; among them, the most common MPs type being polypropylene (PP), mainly occurring as white/transparent fibers with small size (cross section <0.3 mm). SEM images of MPs surfaces revealed multiple features related to environmental exposure and degradation. ATR-FTIR spectroscopy and pyrolysis-GC/MS analyses enabled the accurate identification of MPs separated from the embedding soil micro- and macro-aggregates. Finally, contamination of the polymeric microparticles with a broad range of metals was found by ICP-MS analysis, suggesting that MPs can be vectors for transporting heavy metals in the soil and indicators of soil contamination as a result of mismanagement of industrial wastewaters.

Phycoremediated N-fertilization approaches on reducing environmental impacts of agricultural nitrate leaching

Nitrate leaching is one of the prominent problems of extensive agriculture in attaining maximum yield. Excessive use of nitrogenous fertilizers leads to nitrate (NO3−) pollution in the groundwater and detrimental effects on the environment. In this study, we have phycoremediated the sewage wastewater and evaluated the impact of remediated wastewater on the extent of nitrate leaching in the field condition on the spinach crop. The experiment was set up in polyvinyl chloride (PVC) pipes of dimension 100 cm in length and 30 cm in diameter. The leachates were collected from the depth of 15, 30, 45, 60, and 90 cm to measure the nitrate leaching. The application of microalgal manure significantly reduced NO3− leaching compared to chemically fertilized treatment. The NO3− content in the collected leachate in the treatment T1 at the depth of 0–15 cm (5.03 mg/L), 15–30 cm (5.80 mg/L) and 30–45 cm (4.98 mg/L) was significantly lower than the treatment T5 at the depth of 0–15 cm (8.57 mg/L), 15–30 cm (7.97 mg/L) and 30–45 cm (8.16 mg/L). The reason behind less leaching of nitrate in the algae manure applied treatment was due to the fact, as most of the N fixed by the microalgae present in the form of complex compounds. The leaching could only occur after the mineralization of these compounds. In addition, ammonium content in spinach after harvest was also analysed. Similar to nitrate, the ammonium content was also lesser in phycoremediated manure treatment than chemical fertilizers. The cumulative ammonium content at the depth of 0–15, 15–30 and 30–45 cm in the treatment T1 (121.70 mg/kg) was significantly lower that the treatment T5 (136.43 mg/kg). Optimization methodology of sewage wastewater phycoremediation and its use as adapted N-fertilization presented in this study can be applicable as a policy guideline for sewage wastewater use for irrigation which reduce nitrate leaching and reduce the dependency on the environmentally harmful chemical fertilizers.

Health Risk Assessment and Multivariate Statistical Analysis of Heavy Metals in Vegetables of Khyber Pakhtunkhwa Region, Pakistan.

The level of heavy metals in vegetables grown in soil irrigated with various sources of water and the health risks associated with the consumption of these vegetables were assessed in this study. Samples of water, soil, and vegetables were collected from farmer fields. After digestion in acidic solution, analytical measurements were made using an atomic absorption spectrophotometer. The mean concentration of Pb, Cr, Cd, Cu, Zn, Ni, Fe, and Mn in the soil of two sampling area were in the range from 60.00 to 84.00mgkg-1, 68.00 to 98.00mgkg-1, 1.60 to 2.60mgkg-1, 26.10 to 33.20mgkg-1, 22.60 to 30.80mgkg-1, 50.10 to 78.30mgkg-1, 420.00 to 471.00mgkg-1, and 270.20 to 340.50mgkg-1, respectively. Heavy metals in soil varied significantly at (P ≤ 0.001) among sampling area. The nine heavy metals were divided into two clusters for wastewater and soil, according to cluster analysis. The number of variables was reduced using principal component analysis, which yielded three latent factors, one for wastewater and one for soil. Pb, Cr, Cd, Cu, Zn, Ni, Fe, and Mn concentrations were significantly higher at P ≤ 0.001 in nine vegetables grown on soil irrigated with untreated wastewater than in vegetables grown on fresh-tube well-water-irrigated soil. The health risks associated with metal intake were assessed using the estimated daily intake of metals (EDIM), hazard quotients (HQs), and hazard index (HI). The rates of metal transfer to vegetables have been determined. Except for Pb and Cd, all of the elements' EDMI values were found to be lower than their RfD values. The corresponding HRI values of metals in the various vegetables were found to be below 1, implying that vegetable consumption in the studied region poses no carcinogenic risk. Constant determination of heavy metals in all fruits and vegetables is essential for the assessment of health risks associated with dietary metal exposure. The study has provided valuable information to the general public about the use of wastewater for irrigation of vegetables.

Practice of wastewater irrigation and its impacts on human health and environment: a state of the art

The practice of wastewater irrigation lessens the pressure on the aquatic environment by minimizing the use of freshwater resources. However, this may lead to significant damage to the human health and environments. Recycled wastewater possesses a substantial amount of nutrients that act as fertilizers for crops and facilitate the metabolic action of microorganisms. The major advantages of wastewater irrigation are increased agricultural production, nutrient recycling, reduced stress on freshwater, economical support and provision of livelihoods for farmers. However, several harmful impacts of wastewater irrigation are also prominent due to inappropriate wastewater management and irrigation practices. These include severe hazards to farmer’s health, contamination of agricultural land and crops with toxic metals, chemical compounds, salts and microbial pathogens. In addition, long-term irrigation using wastewater can significantly affect the groundwater through leakage of salty and toxic metal-rich wastewater making it unfit for human consumption. Wastewater irrigation may also alter the physicochemical properties and microbiota of soil, which in turn can disturb land fertility and crop productivity. Several factors need to be considered while using treated or partially treated wastewater for irrigation such as diversity and type of pollutants, available nutrients, pathogenic microorganisms and soil salinity. In this review paper, we assess the impact of wastewater irrigation on humans as well as on the environment based on available case studies globally, outline current use of wastewater for irrigation of agricultural crops such as cereals, vegetables, fodder crops, including agroforestry and discuss suitable management practices of wastewater reuse for irrigation.

The Effect of Wastewater Irrigation on the Activity of Soil Microorganisms

Introduction: The use of wastewater for irrigation in arid and semi-arid regions of the world is increasing. This study aimed to evaluate the effects of wastewater on the microbial activity of irrigated soils using the enzymatic activity of soil microorganisms. Materials and Methods: In this study, for soil irrigation, the secondary effluent of the Isfahan municipal wastewater treatment plant was used. As a control, tap water that has no microbial load was also used. Soil samples were collected in two stages, before and immediately after irrigation. All samples were collected in sterile bags, transferred immediately to the laboratory for physicochemical and microbiological tests. Soil samples were analyzed for the amounts of enzymatic activity (Fluorescein Diacetate (FDA) and dehydrogenase), electrical conductivity (EC), oxidation-reduction potential (ORP), and pH. Results: The EC levels before and after irrigation with tap water was 231.2 and 260.63 µs.cm-1, respectively, which was significantly different from levels of wastewater-irrigated soil (P &lt; 0.05). pH in the two types of used water before and after irrigation was 6-8 and 7-8, respectively. No significant difference was observed in the levels of FDA, dehydrogenase, ORP, and microbial population in samples irrigated with water and wastewaters (p &gt; 0.05). It was found that there is a significant relationship between bacterial density and FDA (P &lt; 0.05). Conclusion: The results of the study showed that irrigation with wastewater has no significant effect on the microbial activity of irrigated soil. Because of the short-term wastewater irrigation in the present study, however, further investigation is needed to evaluate the effect of long-term wastewater irrigation on the microbial and physicochemical quality of soil.

Long-Term Impact of Wastewater Irrigation on Soil Pollution and Degradation: A Case Study from Egypt

There is consensus on the impact of wastewater irrigation on soil properties and heavy metal accumulation. The studies that show the impact of temporal changes as a result of different long-term additions of wastewater on the heavy metal accumulation and degradation of soil are extremely limited. This study was carried out to assess heavy metal contamination in soils irrigated with wastewater for more than 30 years in Egypt. A total number of 12 irrigation water samples and 12 soil profiles were collected during 2020 and were chemically characterized. The results showed that soils irrigated with wastewater over the long term contained significantly higher concentrations of heavy metals compared to fields irrigated with fresh water. Heavy metal levels in water and soil samples were within the permissible limits, with the exception of Cd concentration in water (0.03 mg L−1). Continuous cultivation for a long period of time (30 years) using raw urban wastewater application has led to the adverse effect of increasingly available Pb concentration (5.44 mg kg−1). Similar temporal behavior was seen for Cd and Fe, which increased by 0.98 and 11.2 mg kg−1, respectively, after 30 years. The heavy metals in wastewater-irrigated soils significantly increased in clayey soils, as compared to sandy soils irrigated from the same source. Our findings provide important information for decision makers in Egypt and similar countries for the development of a strategy for the use of wastewater in irrigation for sustainable agricultural management.

SARS-CoV-2 in wastewater from Mexico City used for irrigation in the Mezquital Valley: quantification and modeling of geographic dispersion.

Quantification of SARS-CoV-2 in urban wastewaters has emerged as a cheap, efficient strategy to follow trends of active COVID-19 cases in populations. Moreover, mathematical models have been developed that allow the prediction of active cases following the temporal patterns of viral loads in wastewaters. In Mexico, no systematic efforts have been reported in the use of these strategies. In this work, we quantified SARS-CoV-2 in rivers and irrigation canals in the Mezquital Valley, Hidalgo, an agricultural region where wastewater from Mexico City is distributed and used for irrigation. Using quantitative RT-PCR, we detected the virus in six out of eight water samples from rivers and five out of eight water samples from irrigation canals. Notably, samples showed a general consistent trend of having the highest viral loads in the sites closer to Mexico City, indicating that this is the main source that contributes to detection. Using the data for SARS-CoV-2 concentration in the river samples, we generated a simplified transport model that describes the spatial patterns of dispersion of virus in the river. We suggest that this model can be extrapolated to other wastewater systems where knowledge of spatial patterns of viral dispersion, at a geographic scale, is required. Our work highlights the need for improved practices and policies related to the use of wastewater for irrigation in Mexico and other countries.

Sauaeda Fruticusa is Hyperaccumulator of Chromium and Lead

Sauaeda Fruticusa is Hyperaccumulator of Chromium and Lead