Due to water scarcity, the use of wastewater to irrigate crops is on the rise all over the world, including in Egypt (particularly untreated wastewater). The purpose of this study is to see if irrigation with untreated industrial wastewater in natural fields can cause Abelmoschus esculentus Moench. (okra plant) to accumulate and translocate eight trace metals (lead: Pb, cadmium: Cd, chromium: Cr, copper: Cu, iron: Fe, manganese: Mn, nickel: Ni, and zinc: Zn) in its different tissues. It was extended to look at the effects of wastewater irrigation on the farmed okra plants’ growth characteristics, nutrients, colors, and organic content. Two studied sites at South of Cairo have been investigated: the first site (29°42'31.17" N and 31°15'11.56" E) represented by five cultivated fields irrigated with Nile water (control) and the second site (29°42'37.87" N and 31°17'14.53" E) fields irrigated with effluent received untreated industrial wastewater. Three composite soil and irrigated water samples were collected from each site. Because of wastewater irrigation, soil and plant nutrients (nitrogen, potassium, and phosphorus) decreased significantly (at P < 0.01), whereas trace metals increased significantly (at P < 0.01 and P < 0.05) for soil and plant samples irrigated with untreated wastewater. Due to irrigation with untreated wastewater, there was also a significant decrease in okra growth metrics (at P < 0.05) and leaves photosynthetic pigments: chlorophyll a and b, and carotenoids (at P < 0.01 and P < 0.05). In the plant’s fruits (edible section) watered with wastewater, iron was the most abundant metal. Besides, Cd, Cu, Fe, Mn, Ni, and Zn concentrations were also in the phytotoxic range (42.57, 140.67, 2756.67, 1293.33, 1326.67, and 877.83 mg kg⁻¹, respectively). All trace elements examined accumulate in the roots of wastewater irrigated okra (Bioaccumulation factor > 1). Okra plants, on the other hand, did not have an accumulated trace metals strategy in their shoots since the translocation factor was less than one. Because of substantial trace metal accumulation in their edible sections, the scientists advised against eating okra plants grown in fields watered with untreated wastewater.

The seed extract of Abelmoschus esculentus (AE), also known as Okra, was used as a source of reducing and capping agents to synthesized biogenic titanium dioxide nanoparticles (TiO₂ NPs) due to its rich flavonoid contents. The synthesized AE-TiO₂ nanoparticles were further evaluated by the effect of loading of TiO₂ NPs and irradiation time on the photocatalytic degradation of methylene blue dye. The synthesized TiO₂ NPs were then characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), energy dispersive X-ray spectroscopy (EDS), Fourier transformed infrared (FTIR) spectroscopy, Raman spectra, UV–visible spectrophotometry, and particle size distribution (PSD). The findings confirmed the successful synthesis of the spherical anatase phase of TiO₂ NPs, as well as the existence of phytochemicals in the extract, which were involved in the capping/stabilization of NPs. The synthesized TiO₂ NPs were found to be 60–120 nm in size and almost uniformly distributed throughout the sample. The photocatalytic activity measured in a 300 mL cylindrical photochemical reactor and irradiated with 250 watts UV lamp was investigated based on methylene blue degradation. Effects of irradiation time and catalyst loading were elucidated and correlated with the characteristics of the catalysts. The findings revealed that the synthesized TiO₂ NPs were well-dispersed, stable, and could achieve more than 80 % degradation in 240 min of irradiation with 90 mg/L of AE-TiO₂ NPs loading compared to only 70 % by the commercial one. These results suggested that AE-TiO₂ NPs possesses significant catalytic activity, and the photocatalytic process could be used to degrade, decolorize, and mineralize the methylene blue dye. The polyphenolic tannins present in the extract were the reason behind the desirable characteristics of the nanoparticles and better photocatalytic activity of AE-TiO₂ NPs.

Coagulation and flocculation are two of the steps in the water treatment process in which chemical coagulants based on iron salts or aluminum are used. In order to replace the aluminum or to reduce the concentration of the metal, several natural alternatives to assist in the coagulation/flocculation process have been evaluated, including the use of Abelmoschus escuentus Moench (okra) as a flocculating agent. To determine the degradation time of the okra solution, spectral measurements were performed on the UV–Vis region. The coagulation/flocculation tests were carried out in a jar test equipment, using aluminum polychoride as a coagulant, 1-mgL⁻¹ okra solution as a flocculation aid, and the alkalinizing hydroxide of calcium. Through the spectral measurements and the test in the jar test, it was possible to verify that the solution of the okra remains stable only until the time of 24 h, and after this time, begins the degradation process of the constituents of the okra that promote the flocculation of it. In addition, satisfactory results were obtained in the treatment of water in 24 h, allowing the use of okra as flocculation aid and aluminum polychloride coagulant, as in effluent color removal, with an efficiency of 91 to 96%, and organic matter removal, with an efficiency of 92 to 93.5%.

This study was designed to assess the gradual increase in the use of insecticides on vegetables and to familiarize the consumers regarding the insecticide residues. The purpose of this research work was to highlight the detrimental effects of pyrethroids (bifenthrin, cyfluthrin, cypermethrin, deltamethrin, fenvalerate, lambda-cyhalothrin, and permethrin) compare with dietary intake assessment of eggplant and okra grown in peri-urban environment. In this manner, a total of 180 (n = 60 × 3) samples of eggplant (Solanum melongena) and okra (Abelmoschus esculentus) were procured from the peri-urban farming system of Faisalabad, Multan, and Gujranwala to assess the pyrethroid residues along with their dietary intake assessment. The procured vegetables were quantified for pyrethroid residues by using gas chromatography (GC) equipped with an electron capture detector (ECD). Outcomes of this study revealed that for okra samples, the highest residues of bifenthrin (1.25 mg kg⁻¹) were found in Gujranwala then Multan (1.5 mg kg⁻¹) and Faisalabad (1.04 mg kg⁻¹), whereas in eggplant, the highest residues were recorded for bifenthrin from Faisalabad (1.33 mg kg⁻¹) and Gujranwala (0.78 mg kg⁻¹). In Multan, the highest residues for cyfluthrin (1.18 mg kg⁻¹) were reported in eggplant. Out of all analyzed samples for pyrethroid residues, 32% samples contained detectable residues and 6% samples exceeded their maximum residual limits (MRLs) established by the European Union (EU). Dietary intake assessment (mg kg⁻¹ day⁻¹) was calculated as per their maximum permissible intake (MPI) values, i.e., bifenthrin (1.28), cyfluthrin (1.28), cypermethrin (3.20), deltamethrin (0.64), fenvalerate (1.28), lambda-cyhalothrin (0.064), and permethrin (3.20) respectively. Conclusively, residues from the Multan region were greater than those from Gujranwala and Faisalabad showing excessive application of pyrethroids. Overall results revealed that although some samples exceeded MRLs in selected areas, their safe consumption limit was found.

Eco-degradative features associated with the modern agriculture due to utilization of toxic agro-chemicals and intensified technologies need an urgent attention. Considering this need for eco-curativeness and eco-efficiency, current has for the first time employed an integrated farming system (IFS) through designing an appropriate assemblage of vegetables, poultry, and fish (VPF) and investigated its applied scale practicability in addition to the its role in the enhancement of the productivity and environmental quality maintenance. The practical employment of VPF model resulted in the remarkable improvement of soil fertility through an increment in the essential nutrient quantity. Physicochemical analysis of the soils expressed an improvement in the treated samples, i.e., pH (7.31), EC (0.92 dS/m), organic matter (2.97%), nitrogen (2.1 mg/kg), phosphorous (120.3 mg/kg), potassium (322 mg/kg), calcium (1482.0 mg/kg), and magnesium (471.5 mg/kg). Furthermore, ecological detoxification was expressed in form of lower heavy metals (HM) in the experimental soils. At the early plantation stage, HM concentration in the soils modified with nutrient-rich water signified considerably lower pattern with trend, i.e., Cd < Zn < Ni <Pb< Cu < Fe. The morphological growth of the vegetable plants, i.e., Lycopersicon esculentum L., Capsicum annum, and Abelmoschus esculentus, and fish species, i.e., Lobeo rohita and Clarias gariepinus, in the current investigation was remarkably good. Currently employed VPF model expressed a duality in completion of sustainability goals through production of good-quality vegetables in addition to environmental integrity boosting by complete elimination of need for toxic chemical inputs. Results of this research can be adopted for large-scale employment for production of augmented agricultural production in a completely sustainable manner.

Utilization of Salvinia molesta, an aquatic weed which is notorious for its allelopathy and invasiveness, has been explored by its vermicomposting. Fourier transform infrared spectroscopy (FT-IR) and plant bioassay tests were conducted to analyze the composition and fertilizer value of S .molesta vermicompost. Germination and seedling growth tests were performed in soil supplemented with vermicompost at levels ranging from 0.75 to 40% by weight of the soil on three common food plants, ladies finger (Abelmoschus esculentus), cucumber (Cucumis sativus), and green gram (Vigna radiata). The influence of S. molesta’s vermicompost on some of the physicochemical and biological attributes of the soil was also studied. FT-IR analysis revealed that S. molesta loses its allelopathy, as the chemical compounds that are responsible for it are largely destroyed, in the course of its vermicomposting. There is also an indication that a portion of lignin content of S. molesta is degraded. Vermicompost enhanced the germination success and promoted the morphological growth and biochemical content of the plant species studied. It also bestowed plant friendly physicochemical and biological attributes to the soil. The findings raise the prospect that billions of tons of S. molesta biomass―which not only goes to waste at present but is also a cause of serious harm to the environment―may become utilizable in organic agriculture.