Polluted Irrigation Water Research Articles

Accumulation of microcystin toxin in irrigation water and alfalfa (Medicago sativa) forage plant, and assessing the potential risk to animal health

Microcystin (MC) toxin produced by cyanobacteria has become a significant concern for societies worldwide. The risk of MC in drinking water has been assessed to human health. Nonetheless, its risk to animal health has not been thoroughly evaluated. This study investigated MCs in irrigation water and alfalfa plant from nearby farmlands. Both irrigation water and alfalfa shoots contained greater MC concentrations (1.8–17.4 μg L−1 and 0.053–0.128 μg g−1) during summer than winter (2.4 μg L−1 and 0.017 μg g−1). These MC concentrations showed a correlation with the predominance of cyanobacteria in the sites, triggering the potential risk of these microorganisms in irrigation waters. Accordingly, there would be a high risk (risk quotient, RQ > 1) during summer and a moderate risk (0.1<RQ < 1) during winter for cattle and sheep that drink polluted irrigation water or eat contaminated alfalfa plants. Therefore, the study suggests that cyanotoxins in forage plants and irrigation water sources should be regularly monitored to protect animals from consuming contaminated food and water.

Potential of ecological water treatment elements to reduce pollution of river water used for urban agriculture in Addis Ababa, Ethiopia

Cities in developing countries, such as Addis Ababa, face enormous challenges as a result of high demand for food and clean water, as well as the generation of large amounts of urban waste that is discharged into natural water bodies, contaminating rivers, lakes, and other freshwater bodies used in urban agriculture. Farmers in Addis Ababa and nearby areas use polluted irrigation water diverted from the highly contaminated Little and Great Akaki rivers. The study aimed to assess how well a floating treatment wetland with vetiver grass could reduce irrigation water pollution at the Mekanisa-Gofa-Lafto Cooperative (MGLC) farm in Addis Ababa, Ethiopia. Additionally, the study sought to provide design recommendations that could be implemented at the farmer level. The irrigation water underwent a 7-day treatment using a Vetiver grass floating treatment wetland. A field test was also conducted to evaluate the effectiveness of the floating treatment wetland in reducing pollutants at the study site. The results showed that the floating treatment wetland was able to reduce the Biochemical Oxygen Demand (BOD) (73.68%), Chemical Oxygen Demand (COD) (73.92%), Acidity/Basicity (pH) (0.39%), Chloride (Cl−) (43.12%), Total Hardness (66.56%) and Total Suspended Solid (TSS) (96.21%) values, approaching the recommended irrigation water quality guideline values within 3 days. In contrast, there was an increase in Electro Conductivity (EC) (22.2%) and Sodium (Na) (15.2%) concentrations, which exceeded the recommended values, due to evapotranspiration or the entry of the surrounding soil into the irrigation water of the study site.

Evaluation of ecological and health risks of trace elements in soils of olive orchards and apportionment of their sources using the APCS-MLR receptor model

İzmir, Turkey’s third most populous city, is in an important position in terms of both agriculture and industry. The province, which contributes 9.3% to the country’s industrial production, also has an important potential in terms of olive cultivation. However, until now, no research has been undertaken to analyze the content of trace elements (TEs) in the soil of olive orchards in İzmir. This study was carried out to determine the pollution level and ecological risks of TEs in the olive orchards soils of İzmir province, to reveal their potential sources and to evaluate their health risks. Among the TEs, the average content of only Ni (37.9 mg/kg) exceeded the world soil average content (29 mg/kg), while the average content of only Cd (0.176 mg/kg) exceeded the upper continental crust content (0.09 mg/kg). Enrichment factor revealed that there was significant enrichment for Cd in 73.6%, Ni in 11.6% and Cr in 5.4% of olive orchards, respectively, due to polluted irrigation water and agrochemicals. Similarly, ecological risk factor indicated that there were moderate and considerable ecological risks for Cd in 48.8% and 23.3% of olive orchards, respectively. Absolute principal component scores-multiple linear regression (APCS-MLR) model showed that Ni and Cr in the study area are affected by agricultural sources, Al, Co, Cu, Fe, Mn, Pb and Zn originate from lithogenic sources, and Cd originates from mixed sources. Based on health risk evaluation methods, non-carcinogenic and carcinogenic effects would not be expected for residents. This study provides significant knowledge for evaluating soil TE pollution in olive orchards and serves a model for source apportionment and human health risk evaluation of TEs in other agricultural regions.

Impact of Drip Irrigation with Recycled Wastewater on Aromatic Compound Composition in Capia Pepper (Capsicum annum L.)

In recent years, treating and reusing polluted water for agricultural irrigation has become essential to ensuring water and food sustainability. In addition to the factors affecting human health in vegetables and fruits irrigated with treated wastewater, factors affecting consumer preferences, such as flavor and phenolic compounds, should also be examined. This study investigates the effect of treated wastewater irrigation on the aromatic compounds and phenolic composition of capia pepper, which holds a significant position and is extensively used in various food products in the food industry. Drip irrigation with treated and untreated wastewater from the Kalecik Wastewater Treatment Plant was applied to two pepper varieties in the Kalecik district of Ankara, Türkiye. This research found that wastewater irrigation impacted certain aroma components, including para-dichlorobenzene, alpha-cubebene, hexanoate, alpha-farnesene, limonene, isoamyl butyrate, squalene, and alpha-copaene, which contribute to the distinct aroma and fragrance of capia peppers. Total phenolic content, pH, and soluble solids were found to be high in peppers irrigated with wastewater, and it was observed that these parameters increased as the treatment levels of the wastewater decreased. The highest results were obtained in capia peppers irrigated with wastewater. Results indicate that heavy metal levels in peppers align with permissible limits, confirming the usability of both water sources. In the face of global water scarcity and the challenge of feeding an ever-growing population, studies like this offer valuable insights into sustainable and well-informed agricultural practices.

Antimicrobial Effects of Plant-Based Supplements on Gut Microbial Diversity in Small Ruminants.

Every year in the United States, approximately 48 million people are affected by bacterial illnesses that are transmitted through food, leading to 3000 fatalities. These illnesses typically stem from food animals and their by-products, which may harbor dangerous pathogens like Salmonella enterica, Listeria monocytogenes, enterohemorrhagic Escherichia coli O157:H7, and Campylobacter jejuni. Factors that contribute to contamination include manure used as a soil amendment, exposure to polluted irrigation water, and contact with animals. To improve food safety, researchers are studying pre-slaughter intervention methods to eliminate bacterial contamination in live animals. While small ruminants are vital to global agriculture and income generation for small farms, traditional feeding practices involve supplements and antibiotics to boost performance, which contributes to antibiotic resistance. Hence, researchers are looking for friendly bacterial strains that enhance both animal and human health without impacting livestock productivity. The global trend is to minimize the use of antibiotics as feed supplements, with many countries prohibiting or limiting their use. The aim of this review is to provide a comprehensive insight on the antioxidant capabilities, therapeutic attributes, and applications of bioactive compounds derived from sweet potato tops (SPTs), rice bran (RB) and radish tops (RTs). This overview provides an insight on plant parts that are abundant in antioxidant and prebiotic effects and could be used as value-added products in animal feed and pharmaceutical applications. This review was based on previous findings that supplementation of basal diets with natural supplements represents a multifaceted intervention that will become highly important over time. By remarkably reducing the burden of foodborne pathogens, they apply to multiple species, are cheap, do not require withdrawal periods, and can be applied at any time in food animal production.

Enhancing The Quality of Irrigation Wastewater for Mung Bean Cultivation Using IoT Technology

Farmers use irrigation channels to irrigate agricultural fields for mung bean cultivation in Indonesia. However, irrigation water in some areas is heavily contaminated and foul-smelling, which can hinder the growth of mung bean plants. Treating irrigation wastewater with methods tailored to the plants’ needs can reduce the levels of contaminants present in the waste-laden irrigation water. This research uses three samples of water wastewater before, after, and PDAM water. This research aims to process polluted irrigation water to produce clean water that meets the quality standards required for plant irrigation. This study employs anaerobic filter technology and IoT-based phytoremediation processes. The results obtained from the wastewater treatment research include adjusting the water pH to 7, reducing COD levels by 41.55%, BOD by 54.6%, phosphates by 23.13%, and nitrates by 90.22%. The comparison obtained from the experiment of watering the green bean plants using three water samples, namely irrigation wastewater before and after being treated, and PDAM water, showed that irrigation wastewater grew faster with a percentage of 65.33%, sewage irrigation water before being treated reached 49.33%, and PDAM water reached 53.33%. The treated water is then supplied to mung bean plants, promoting faster and healthier growth because the water nitrate, BOD, COD, and Phosphate decrease.

Pb(II) Uptake from Polluted Irrigation Water Using Anatase TiO2 Nanoadsorbent.

The adsorption characteristics of titanium dioxide nanoparticles (nano-TiO2) for the removal of Pb(II) from irrigation water were investigated in this work. To accomplish this, several adsorption factors, such as contact time and pH, were tested to assess adsorption efficiencies and mechanisms. Before and after the adsorption experiments, commercial nano-TiO2 was studied using X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM), energy dispersive spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). The outcomes showed that anatase nano-TiO2 was remarkably efficient in cleaning Pb(II) from water, with a removal efficiency of more than 99% after only one hour of contact time at a pH of 6.5. Adsorption isotherms and kinetic adsorption data matched the Langmuir and Sips models quite well, showing that the adsorption process occurred at homogenous sites on the surface of nano-TiO2 by forming a Pb(II) adsorbate monolayer. The XRD and TEM analysis of nano-TiO2 following the adsorption procedure revealed a non-affected single phase (anatase) with crystallite sizes of 9.9 nm and particle sizes of 22.46 nm, respectively. According to the XPS data and analyzed adsorption data, Pb ions accumulated on the surface of nano-TiO2 through a three-step mechanism involving ion exchange and hydrogen bonding mechanisms. Overall, the findings indicate that nano-TiO2 has the potential to be used as an effective and long-lasting mesoporous adsorbent in the treatment and cleaning of Pb(II) from water bodies.

Removal of Pb2+ and Cd2+ from irrigation water and replenishment of mineral nutrients using a low-cost mineral adsorbent derived from potassium-rich aluminum silicates

Heavy metal pollution and a lack of essential mineral nutrients in irrigation water seriously impact crop safety and quality. A low-cost mineral adsorbent (LCMA) was created using mechanochemical methods from illite, wollastonite, gypsum, dolomite, and calcium carbonate (molar ratio of 2:1:1:3:9) to remove Pb2+ and Cd2+ and supplement mineral nutrients in irrigation water. The results showed that LCMA had a higher removal capacity than most similar mineral materials, with maximum adsorption capacities of 278 and 83.1 mg·g–1 (298 K) for Pb2+ and Cd2+, respectively. At pH ≥ 3, there was very little Pb2+ and Cd2+ desorption from LCMA, whereas desorption was simple at pH ≤ 0.5, indicating the chemical stability of LCMA. Pb2+ and Cd2+ are competitive adsorptions, with Pb2+ taking precedence. In actual irrigation water, the removal rates of Pb2+ and Cd2+ by LCMA were approximately 90 % and 80 %, respectively, within 10 min. Complexation and co-precipitation were used to attach Pb2+ and Cd2+ to LCMA, followed by ion exchange and electrostatic interaction. Pb2+ was primarily adsorbed on LCMA as PbAl2O4, Pb2SiO4, and PbSO4, whereas Cd2+ was primarily adsorbed as Cd3Al2Si3O12 and CdSiO3. In addition, with the application of LCMA, the concentrations of Si4+, K+, Ca2+, and Mg2+ in the polluted irrigation water increased by 12.4 %, 22.8 %, 78.9 %, and 439 %, respectively. LCMA is a strong candidate to replace the current expensive remediation technology for heavy metal pollution and lacking mineral nutrients in irrigation water.

Removal of lead (Pb+2) from contaminated water using a novel MoO3-biochar composite: Performance and mechanism

Removal of toxic chemicals from the environment using novel adsorbents is of great concern. In this study, a novel composite of molybdenum trioxide (MoO3)-engineered biochar (MoO3-BC) was derived from corn straw and synthesized for the removal of Pb(II) from water. The pyrolysis temperature of 600 °C was suitable for the thermal self-assembly of MoO3-BC. Although MoO3-BC had lower SBET (59.3 m2/g) than the pristine BC (157.8 m2/g), it had a stronger adsorption affinity to Pb(II). The Pb(II) removal capacity of MoO3-BC was 229.87 mg/g at pH 4.0, and the adsorptive removal of Pb(II) was fit using a pseudo-second-order model and the Langmuir model. High temperature favored the removal of Pb(II) by MoO3-BC; However, the removal of Pb(II) was inhibited with increasing the ion strength. The MoO3-BC revealed an acceptable stability and reusability, since the removal efficiency of Pb(II) remained above 80.7%, even after 8 cycles. The MoO3-BC effectively reduced ≥99.9% of Pb(II) in the polluted irrigation water. The Pb(II) removal mechanisms involved surface electrostatic attraction, ion exchange and surface complexation. These findings conclude that the MoO3-BC is a novel composite that can be used for the removal of Pb from contaminated water. More studies are needed to investigate the potentiality of MoO3-biochar composite for the removal of other metals from water in a mono and competitive sorption system.

Health Risks for a Rural Community in Bokkos, Plateau State, Nigeria, Exposed to Potentially Toxic Elements from an Abandoned Tin Mine.

The past mining activities in Bokkos Local Government Area (LGA) were performed in an uncontrolled way and gave rise to many abandoned ponds now serving as domestic and irrigation water sources. Past research focused mainly on the environmental impact, and we show for the first time what the human health risk through consumption of contaminated food crops is in these communities. This study was designed to determine the level of Potentially Toxic Elements (PTEs) contamination in pond water, soil, and food crops and assess the health risk of inhabitants in the abandoned tin mining community in Bokkos LGA. Samples of the mining pond water, soil, and selected food crops from farms irrigated with the pond water: bitter leaf (Vernonia amygdalina), pepper (Piper nigrum), okra (Albelmoschus esculentus), maize (Zea mays), sweet potato (Ipomoea batatas), and Irish potato (Solanum tuberosum) were analyzed for each of the eight PTEs (viz. Cu, Cr, Fe, Mn, Ni, Zn, Cd, and Pb) using inductively coupled plasma optical emission spectrometry (ICP-OES). The results obtained showed that the levels of all the PTEs analyzed in the soil, pond water, and selected food crops except for Fe and Mn in soil and Cd in sweet potato were greater than their corresponding background area values (p < 0.05). Also, the mean concentrations of all the PTEs except for Cu in pond water were significantly (p < 0.05) higher than the WHO maximum permissible limit. With the exception of Fe, Ni, and Zn for pepper and okra, Cu and Fe for maize grains as well as Cu, Ni, and Zn for sweet and Irish potatoes and Fe and Cd for sweet potato, the mean concentrations of PTEs in the food crops were significantly higher than WHO maximum permissible limit. The EF values of Cd (0.39); Cu (3.59) and Ni (2.81); Cr (9.38) and Pb (17.84); and Mn (178.13) and Zn (83.22) classified the soil as minimally, moderately, significantly, and extremely highly enriched, respectively. The PI values of all the PTEs in the soil studied were all greater than 5, indicating that the soils were severely contaminated. There was evidence that food crops significantly bioaccumulated PTEs either as a result of contaminated soil and/or irrigation water. The bioaccumulation was not uniform and was dominated by transfer from the polluted irrigation water. The bitter leaf, okra, and to some extent maize had the highest transfer of PTEs, and Mn, Cu, and Zn had the highest bioaccumulation in the food crops investigated. The hazardous index (HI) for the eight PTEs through the consumption of food crops was 107 for children and 33 for adults which greatly exceeded the recommended limit of 1, thus indicating that possible health risks exist for both local children and adults. For every PTE, the values of HI for children are many-fold higher than those for adults, which is of particular concern due to the high HI values for Pb found for maize consumption, a typical staple food. The cancer risk values for Cr and Ni for all the food crops were within 10-3-10-1 which is several fold higher than the permissible limits (10-6and < 10-4) indicating the high carcinogenic risk. It can be concluded based on the results and risk assessment provided by this study that human exposure to mining pond water and soil in farms around the mining pond through the food chain suggests the high vulnerability of the local community to PTE toxicity. Long-term preventive measures to safeguard the health of the residents need to be put in place.

Application of a soil quality triad in assessing ecological risk posed to croplands

Healthy soil ecosystems fulfil multiple functions (e.g. cycling nutrients and controlling pests), which play an important role in sustainable food production. However, the application of polluted irrigation water poses a major risk to soil quality (health) and warrants investigation to ultimately inform decision-making. We hypothesised that the standardised soil quality TRIAD approach (ISO 19204), which integrates the chemistry, ecology, and ecotoxicology lines of evidence, can be used as part of an ecological risk assessment of cropland soils. To investigate the applicability of this approach in an agricultural setting, we collected soils from croplands associated with the Hartbeespoort and Crocodile (West) irrigation schemes, which utilise water known to be heavily impacted by anthropogenic (metal, nutrient, and salt) pollution. Croplands associated with the Marico-Bosveld Irrigation Scheme served as the reference systems. Data from the three lines of evidence were scaled, weighted, and integrated. Moderate risk was evidenced for nutrient and salt content in most croplands associated with the Hartbeespoort Irrigation Scheme. However, either no or low risk was recorded for the ecology and ecotoxicology lines of evidence. Finally, the integrated risk assessment concluded that only low ecological risk was posed to soil quality, likely as a result of agricultural activities (e.g. tillage and fertiliser application) that deteriorated soils also at the reference system. This study shows important limitations in the application of ecological risk assessments in conventionally farmed soils, but still holds promise for organic and conservation systems.&#x0D; Significance:&#x0D; &#x0D; A pollution linkage between irrigation water and cropland soils was evidenced, but presented only minimal risk to soil quality.&#x0D; Conventional agricultural practices (e.g. tillage) mask the risk posed by environmental pollution and impair the applicability of ecological risk assessments.&#x0D; It is possible that this approach can be applied in less disturbed crop production systems, for example in conservation (regenerative) and organic croplands.&#x0D;

Occurrence of Chemical Contaminants in Peruvian Produce: A Food-Safety Perspective.

The presence of chemical contaminants in agricultural products is a continued food-safety challenge in Peru. This country has robust agriculture potential, but its output of fruits and vegetables is severely impacted by massive mining activities, as well as poor farming practices, including the use of polluted irrigation water, misuse of pesticides, and inadequate postharvest conditions. This review examines the current scientific knowledge on the levels of pesticide residues, heavy metals, and mycotoxins on crops produced in Peru. The available data shows that several crop varieties are contaminated with these classes of chemical contaminants, and at levels that exceed the national and international permissible limits. The abundance of chemical contaminants in produce indicates a relevant food-safety issue, which increases the risks of chronic human diseases, like cancer—a leading cause of death in Peru. Finally, this review presents recommendations to address these contamination problems in produce grown in the Andean country.

Validation of an Analytical Workflow for the Analysis of Pesticide and Emerging Organic Contaminant Residues in Paddy Soil and Rice.

Contamination of agricultural soil with organic contaminants is a global problem due to the risks associated with food security and ecological sustainability. Besides the use of agrochemicals, hundreds of emerging contaminants enter arable lands through polluted irrigation water. In this study, an analytical workflow based on QuEChERS extraction coupled with LC-MS/MS quantification was applied to measure 65 emerging contaminants (42 pesticides and 23 multiclass industrial chemicals) in soil and rice for the first time. The method was validated on paddy and yard soil and rice plants. A recovery efficiency ranging between 70 and 120% (RSD <20%) was achieved for more than 70% of the analytes. Then, the validated method was used to quantify target contaminants in 22 soil and 9 rice samples collected mainly from paddy fields close to the Ergene River (Turkey), which is a highly polluted river used for irrigation in the region. Pesticide residues were present in all soil samples up to 2.4 mg/kg. However, their concentrations were below their maximum residual limits in rice. Azoxystrobin, prochloraz, propiconazole, imidacloprid, and epoxiconazole were the most frequently detected pesticides. In addition, industrial pollutants such as benzyldimethyldodecylammonium and tris(2-butoxyethyl) phosphate were detected in paddy soil samples at concentrations between 0.1 and 691 μg/kg. Benzyldimethyldodecylammonium and 5-methyl-1H benzotriazole were also measured in rice at concentrations up to 0.26 and 2.13 μg/kg, respectively.

Trace Metal Accumulation in Water, Soil and Crop Plants along the Basin of Ujjani Reservoir, India

The excessive application of fertilizers and of polluted irrigation water increases the trace metal level in an agricultural ecosystem. This study aimed to assess the concentrations of trace metals (Fe, Cu, Mn, and Zn) in irrigation water, field soil and crop plants. The contents of metals were analyzed by Atomic Absorption Spectroscopy. The range and hierarchy of trace metals concentration (µg/ml) in irrigation water are as follows, Fe (2.16 - 1. 53) > Zn (0.30 - 0.17) > Cu (0.18 - 0.11) > Mn (0.11-0.09). The concentration (µg/g) range in field soil showed in an order as Fe (9000- 6961.5) > Mn (984.6-408.9) > Cu (698.5-26.3) > Zn (145.3- 22.9). Moreover, crop plant parts showed maximum concentration (µg/g.dry weight) range for metal Fe (516.3 - 126.7) followed by Mn (169.7-0.4), Zn (78.8- 50) and least for metal Cu (70.5- 4.1). It was noticed that the Fe concentration in irrigation water is higher than the water quality standards proposed by the Food and Agriculture Organization. Furthermore, the field soil exhibited more Cu, and crops have accumulated excess Fe and Cu than the Indian and European Union guidelines. Further, we reported that among the all plant part, leaves are more prone to accumulate trace metals. The value of the transfer factor indicates that plant has low bioaccumulation potential for studied trace metals. Whereas the accumulation index shows that there is a significant Cu contamination in the field soil. So we suggest that farmers should avoid the application of copper-rich fertilizers.

Impact of Urban Sprawl on Agriculture Lands in Greater Cairo

Since the 1950s, The Greater Cairo Metropolitan Region (GCMR) has experienced an unprecedented rate of informal urbanization over productive arable lands, forming fragmented landscape and accompanied with significant socioeconomic influences. Recent data show that 62% of Greater Cairo and 87% of Giza are informal settlements resulting from urban sprawl, with 80% of these informal settlements built on privately owned agriculture lands. Beside the direct loss of agricultural land, the fragmented agricultural lands, created by urban expansion, road networks, and constructions, suffers from indirect impacts on the inputs of agricultural processes, such as increased irrigation requirements, soil contamination. This study aims to develop a conceptual framework illustrating the interrelationship between urban sprawl and agricultural activities through a case study on one district (Tersa District) in the Giza governorate. The study implemented both qualitative and quantitative data collection techniques as well as water samples analysis. Data were collected through structured questionnaires and in-depth interviews with 30 farmers, 50 residents, and governmental authorities to investigate changes in the different facets of agricultural activities over a 10-year period from 2007 to 2017. Changes in agricultural activities were assessed in terms of changes in cultivated land ownership, agricultural laborers, agricultural cooperative organization support to farmers, crop type, and livestock management activities. To evaluate the possible impact of urban sprawl on water quality, water samples in four locations were analyzed. The research affirms that urban sprawl has led to loss of about 19% of Tersa’s fertile agricultural lands between 2007 and 2017 and revealed many challenges facing farmers in the remaining fragmented lands due to urban sprawl, including polluted irrigation water, diminishing soil fertility, increased labor wages, reduction of institutional support, and alteration of crop type. The similarity of these challenges with other challenges identified in the international literature provided the needed background to propose a framework exploring the interrelationship between urban sprawl and agricultural activities. This framework can highlight entry points for various interventions to ameliorate and address the negative impact of urban sprawl in remaining agricultural areas. In addition to the most foremost intervention of intensifying efforts to control urban sprawl, ensuring sustained good quality of irrigation water, efficient institutional support, and building channels of communication and trust among members of the communities can support the sustainability of agricultural activities and enhance food security in these areas.

Critical load model and pollution indices application for water–soil–plant system assessment around El-Hammam canal, East El-Alamein, Egypt

El-Hammam canal, East El-Alamein City, is one of the national sustainable projects for facing food shortage in Egypt. The current work was conducted to evaluate the water–soil–plant system quality concerning potential toxic elements (PTEs) in this area. Surface water, soil and fruit samples were collected and analyzed for their content of As, Cd, Cr, Cu, Ni and Pb. The studied soils are sandy calcareous alkaline soil with low organic matter content. The potential ecological risk index (PERI) indicated that most soils were of very high PERI owing to the elevated Cd and to less extent As and Ni. Unfortunately, most of the recorded Cd and Pb appeared in the bioavailable fraction. The studied water samples contained acceptable levels of ions for irrigation, except Cd, Cu and Ni. Both apple and peach contained acceptable concentrations of PTEs, except peach that contains an elevated level of As. It was observed that the concentration of PTEs in peach was higher than the apple. The bio-concentration factor values of PTEs in apple and peach indicated that fruits were excluders of the PTEs. The study area contains critical loads of the studied PTEs, especially As, Cr and Ni, which mostly attributed to the plant uptake of PTEs. The uptake of plants (harvested part) of these toxic elements can be cause of many health problems. Pesticide sprays may be the source of these elements leaching on plant surfaces. Finally, the study area content of PTEs can be attributed to the polluted irrigation water and agrochemical.

Effect of industrial wastewater on wheat germination, growth, yield, nutrients and bioaccumulation of lead

Due to fresh water scarcity, farmers are using polluted water for irrigation. This research was conducted to study the bioaccumulation of Pb in wheat (Cv. Shafaq-2006). The experiment was comprised of seven treatments of lead i.e. 0–1,000 mg Pb/kg. The results revealed that lead severely reduces germination (− 30%), seedling fresh weight (− 74%), seedling dry weight (− 77%), vigor index (− 89%), tolerance index (− 84%), plant height (− 33%), number of leaves (− 41%), root fresh weight (− 50%), shoot fresh weight (− 62%), root dry weight (− 63%), shoot dry weight (− 71%), and root length (− 45%). The physiological parameters also respond negatively like stomatal conductance (− 82%), transpiration rate (− 72%) and photosynthetic rate (− 74%). Similarly, biochemical parameters also showed negative impacts, like carotenoids (− 41), total chlorophyll (− 43), chlorophyll a (− 42) and chlorophyll b (− 53). Yield parameters like the number of seed/plant, seed weight/plant, 1,000 seed weight and harvest index were reduced by 90%, 88%, 44% and 61%, respectively in T6. In addition, protein contents (− 81%), phosphorous (− 60%) and potassium (− 55%) were highly effected in the highest lead concentration (T6). Lead accumulation was extremely higher in seeds (119%) as compared to control plants. Lead bio-accumulation above threshold concentrations in crop parts is a serious human health concern.

Pre- and Post-Harvest Practices of Urban Leafy Green Vegetable Farmers in Accra, Ghana and Their Association with Microbial Quality of Vegetables Produced

Vegetable farming is the most practiced urban agriculture in Ghana. A previous study of our laboratory revealed poor microbial quality of, and presence of Salmonella on, leafy green vegetables grown or sold in Accra, Ghana. The aims of this study were to determine agricultural practices of urban vegetable farmers and the association between agricultural practices and microbial safety of vegetables produced. A survey was conducted among 102 farmers from 12 farming areas who produced exotic and indigenous leafy greens in Accra, Ghana to identify their farming practices. It was observed that water from waste drains pumped into shallow wells was used for irrigation by 70% of the farmers. Incompletely composted manure was commonly used (99%) in farming. Vegetables were usually harvested using bare hands (96%) and knives (73%) and transported mainly in sacks (94%) to market centers under non-refrigerated conditions. Over 60% of the farmers disagreed that the use of polluted irrigation water can contaminate vegetables or make consumers sick. According to the seemingly unrelated regression model, farmers with no formal education and less food safety knowledge and had been planting on their current farmlands for several years were likely to produced vegetables with higher fecal coliform and Enterococcus sp. counts compared to other farmers. Vegetables cultivated by farmers who disagreed that the use of contaminated water can make consumers sick were associated with the production of vegetables with high fecal coliform and Enterococcus sp. counts. Education and improved agricultural and post-harvest handling practices should be encouraged among vegetable producers in the area to improve food safety.

Removing tetracycline and Hg(II) with ball-milled magnetic nanobiochar and its potential on polluted irrigation water reclamation

The feasibility of ball-milled magnetic nanobiochars (BMBCs) derived from wheat straw for adsorptive removal of tetracycline (TC) and Hg(II) from aqueous solution was assessed against that of pristine magnetic biochars (PMBCs). Ball milling conversion of PMBCs into BMBCs greatly improved TC and Hg(II) removal, and ≥ 99% TC and Hg(II) were adsorbed by BMBC prepared at 700 °C (BMBC700) within 12 h. The maximum adsorptive removal capacities of BMBC700 for TC and Hg(II) were 268.3 and 127.4 mg/g, respectively. The amounts of TC and Hg(II) removed by BMBC700 decreased gradually as the ionic strength of the solution increased, but increased as the solution temperature increased from 25 to 45 °C. The further FTIR and XPS analysis confirmed removal of TC was predominately regulated by the combination of electrostatic interactions, hydrogen bonds, and Cπ–Cπ interaction, while, the adsorption of Hg(II) was mainly governed by several mechanisms, including electrostatic attractions, Hg–Cπ bond formation, and surface complexation. Overall, BMBC700 presented great potential for TC and Hg(II) removal from polluted irrigation water and exhibited acceptable recyclability performance as well as magnetic separation advantage in use.

Numerical Simulation of Groundwater Flow and Vulnerability in Wadi El-Natrun Depression and Vicinities, West Nile Delta, Egypt

ABSTRACT During the last 25 years, rapid and unplanned land reclamation activity has been carried out in the areas located in both south and east of Wadi El - Natrun Depression of Egypt. Accordingly, negative effects on groundwater levels and vulnerability are frequently caused by localized high levels of abstraction and the return-flow of polluted irrigation water respectively. A groundwater model is a computational method that presents an approximation of an underground water system. In this study the groundwater system is simulated both in quantity and quality by using Mass Balance Transfer Model (NETPATH), Groundwater Modeling System (GMS) and DRASTIC Model to investigate the water - rock interactions, groundwater levels drawdown and vulnerability respectively. Three main geochemical processes namely dedolomitisation, dissolution of halite and silicate weathering were estimated during the flow path. The present over-abstraction of groundwater (105.84 million m3/year) has induced a general head drawdown from 3 to 40 m in years 2015 and 2050 respectively. Best estimate using a 3D GMS hydraulic model was (157000 m3/day) a strategy proposed for the management of groundwater without critical depletion (second scenario). The results document the extent to which a high drawdown can greatly reach 4 m by the end of simulation year 2050. The vulnerability maps of groundwater were constructed using the DRASTIC index method. The results indicated that, the southeastern and central portions of the study area are having high vulnerability rate (&amp;gt; 110). Modified DRASTIC map showed many more dominant high risk areas in the eastern parts of the study area that were low risk, which may be attributed to return flow of polluted irrigation water.