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Morocco, like other arid and semi-arid countries, faces a growing water shortage, necessitating the exploration of alternative solutions. This study investigates the potential use of untreated urban wastewater for irrigation and environmental impact mitigation, focusing on El Jadida as a case study. Throughout the year 2023, from January to December, a comprehensive characterization of physico-chemical, heavy metal, and biological parameters of this unconventional water source was conducted to account for seasonal variations, particularly between rainy and sunny periods. Samples were collected at the inlet of the El Jadida wastewater pre-treatment plant (WWTP) to assess the city's net pollution levels. Results indicate high values for chemical oxygen demand (COD = 741 mg/L), biological oxygen demand (BOD5 = 344 mg/L), organic load (BOD5/COD ratio = 2.2), and biodegradability, suggesting a strong need for biological treatment. Despite compliance with discharge standards, concentrations of heavy metals such as mercury (Hg), cadmium (Cd), aluminum (Al), manganese (Mn), and fluoride ions (F-) exceed Moroccan irrigation water quality thresholds by 90%, 66.7%, 21.8%, 33.3%, and 86.1%, respectively. Therefore, advanced chemical treatment is highly recommended to mitigate environmental impact and ensure safe reuse for irrigation. The novelty of this study lies in evaluating the suitability of El Jadida's wastewater for irrigation and environmental impact mitigation, underscoring the critical need for effective treatment solutions to enhance water sustainability in Morocco. Future research will focus on optimizing water treatment processes.

Abstract Microbial fuel cells (MFCs) have attracted a great deal of attention as a promising technology for recovering electricity from organic substances by harnessing the metabolic activities of microorganisms. The objective of this study is to assess the efficacy of a LiTa0.5Nb0.5O3/g-C3N4 (LTN/g-C3N4) heterojunction as a photocathode catalyst within a single-chamber microbial fuel cell operating under both light irradiation and dark conditions. X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Energy dispersive X-Ray spectroscopy (EDS) were used to conduct a comprehensive analysis of the composite catalyst, revealing its exceptional purity and unique properties. After 120 h of exposure to visible light, the maximal power density of the MFC containing LTN/g-C3N4-modified carbon cloth was determined to be 667.7 mW/m3. The power density achieved with the presence of light was approximately three times greater than the power density obtained without light in the MFC (235.64 mW/m3). In addition, the study determined that the removal efficiencies of chemical oxygen demand (COD) were 88.4% and 66.5% when exposed to light and in the absence of light, respectively. These findings highlight the potential of the non-precious LTN/g-C3N4 photocatalyst as a viable alternative for effective wastewater treatment and power generation in microbial fuel cells with a single chamber configuration.

Wastewater from wastewater treatment plants (WWTPs) often requires further treatment before it can be safely reused. Lime is a common and affordable material used for this purpose, but its production can generate significant environmental impacts. This study developed an eco-friendly and effective lime substitute from eggshell waste for wastewater treatment. First, pre-treated wastewater effluent from WWTP El Jadida, Morocco, was collected and characterized. It was found that COD, BOD5, and TSS values showed non-conformity from Moroccan discharge standards, as well as high concentrations of heavy metals such as cadmium (Cd), zinc (Zn), aluminum (Al), chromium (Cr), manganese (Mn), lead (Pb), silver (Ag), beryllium (Be), copper (Cu) and cobalt (Co). These pollutants represent a potential risk to human health and the environmental ecosystem. To reduce this pollution, the optimal mass of lime powder obtained by thermal treatment of eggshell waste was determined by testing a concentration series of 6, 12, 18, 24, 30, and 36 g/L. The findings confirmed that the addition of the optimal dose of prepared lime (24g/L) resulted in a significant reduction in pollution parameters, with abatement rates of 77% for BOD5, 63% for COD and 66% for TSS, respectively. Furthermore, the eco-friendly lime substitute also showed promise in reducing the colorization rate for dyes by 84% and removing heavy metals through precipitation. However, the generated by-product loaded with toxic pollutants should be encapsulated in eco-materials to ensure safe operation and contribute to a sustainable management strategy for wastewater treatment.

Toxic contamination of agricultural soils by trace metal(oid)s can pose detrimental effects on human health and agroecological systems. In this view, the current research explored total and available metal(oid)s in surface soils and assessed the associated hazards using pollution indices, PMF modeling, PCA, and Montecarlo probabilistic human risk assessment with 10,000 repetitions. The mean concentrations of Cd, Pb, As, Cr, Ni, Cu, Zn, and Fe were 0.89, 24.86, 1.81, 19.10, 25.44, 7.98, 49.12 and 6183.32 mg kg−1 dry weight, respectively. These findings highlighted that the concentration of pollutants exceeded the values measured in the geochemical background. Soil enrichment by heavy metal (oid)s was confirmed by analyzing available fractions using DTPA ,CaCl2 and enrichment factor (EF). Additionally, pollution indicators (Igeo, PLI, and PERI) displayed significant contamination levels, with a higher ecological risk. Matrix Factorization (PMF) receptor and multivariate statistical analysis reflected that anthropogenic activities, particularly landfilling and agricultural practices were the main causes of the contamination. Furthermore, probabilistic and deterministic human risk assessments showed that carcinogenic risks exceeded the threshold values (10−4) set by the USEPA. Consequently, it is crucial to implement continuous monitoring and supervision of landfill sites to prevent additional pollution. These measures should be integrated into the management plans for waste management.