Through their accumulation in soils, microplastics have recently become a matter of concern. The aim of this review is to assemble and investigate the recent studies about microplastics in soil by focusing on their sources, occurrence, fate in soil, and analytical methods. The objective is also to clarify and elucidate their potential impacts on soil fauna, plants and microorganisms. In this paper, articles reporting the quantity of microplastics and their characteristics in soil at 62 sites situated across 17 countries were reviewed. The land type, microplastic abundances, types and sizes were compared. We summarized and discussed the sampling and analytical methods used and the variation of microplastic concentration according to their sources. The data showed that microplastic in soil from available global studies ranged from 0 to 3573×10³ particles kg^-1, with major dominance of polyethylene, polystyrene and polypropylene found in 50, 37 and 32 studies, respectively. The data analysis showed the high migration of small particles, spherical shape with high polymer density in the major studies. We also described the mechanisms controlling the vertical transport of microplastics: agricultural activity (plowing: at a depth between 10 cm (very shallow plowing) and 40 cm (deeper soil tillage)), bioturbation by soil organisms and plants, and leaching that can lead to the contamination of the groundwater. This review elucidated the behavior and fate of microplastics within the soil, serving as a reference for upcoming studies aimed at devising solutions to mitigate the toxicity associated with microplastics in soil.

We conducted surveys of Mediterranean beaches in Egypt, Morocco, and Tunisia including 37 macro-litter (> 25 mm) and 41 meso-litter (5–25 mm) assessments. Our study identified key litter items and assessed pollution sources on urban, semi-urban, tourist, and semi-rural beaches. Macro-litter concentration averaged 5032 ± 4919 pieces per 100 m or 1.71 ± 2.28 pieces/m², with higher values observed on urban (mean 2.63 pieces/m² ± 3.03) and tourist (mean 1.23 pieces/m² ± 0.91) beaches. Similarly, urban (mean 9.91 pieces/m² ± 12.70) and tourist beaches (mean 5.32 pieces/m² ± 4.48) revealed elevated levels of meso-litter contamination, particularly in the upper third of the beach, which contained the highest quantities both in terms of number (51%) and weight (50%). 55% of the macro-litter and 35% of the meso-litter originated from human shoreline activities and poor waste management. Given the width of some beaches and their high levels of pollution, the standard 100 m macro-litter approach was impractical. To enable cost-effective, long-term monitoring, we adapted it to a faster 10 m transect approach, which provided reliable data on the top 25 litter items, accounting for 82% of beach pollution. Our Sand Rake method effectively quantified pollution on both cleaned and uncleaned beaches, addressing the often neglected meso-litter size fraction. The high pollution levels, top litter items, and identified sources indicate that beach cleaning alone will not solve the pollution problem. Efforts to raise environmental awareness, enhanced waste management, and law enforcement are needed to improve the situation in a sustainable way.

Hexavalent chromium removal from the environment remains a crucial worldwide challenge. To address this issue, microbiological approaches are amongst the straightforward strategies that rely mainly on the bacteria's and fungi's survival mechanisms upon exposure to toxic metals, such as reduction, efflux system, uptake, and biosorption. In this work, scanning electron microscopy, energy-dispersive X-ray spectrophotometry, Fourier transform infrared spectroscopy, and zeta potential measurements were used to investigate the ability of chromium adsorption by Bacillus licheniformis, Bacillus megaterium, Byssochlamys sp., and Candida maltosa strains isolated from tannery wastewater. Scanning electron microscopy combined with energy dispersive X-ray spectroscopy revealed alterations in the cells treated with hexavalent chromium. When exposed to 50 mg/L Cr⁶⁺, Bacillus licheniformis and Candida maltosa cells become rough, extracellular secretions are reduced in Bacillus megaterium, and Byssochlamys sp. cells are tightly bound and exhibit the greatest Cr weight percentage. In-depth analysis of Fourier transform infrared spectra of control and Cr-treated cells unveiled Cr-microbial interactions involving proteins, lipids, amino acids, and carbohydrates. These findings were supported by zeta potential measurements highlighting significant variations in charge after treatment with Cr(VI) with an adsorption limit of 100 mg/L Cr⁶⁺ for all the strains. Byssochlamys sp. showed the best performance in Cr adsorption, making it the most promising candidate for treating Cr-laden wastewater.

This study aims to select fungi isolates to reduce olive mill wastewater (OMWW) chemical oxygen demand (COD) and phenolic compounds (PC), as well as their genotoxicity effect. Treatment with mold, isolated by an innovative technique using phenolic compound-selective media, showed a reduction rate of about 4% for COD and 2% for PC during one month of incubation without optimization of the treatment conditions. Whereas this percentage reached 98% and 96% for COD and PC, respectively, after only 12 days of treatment, when the C:N ratio was adjusted to 30 by adding urea as a nitrogen source at 150 rpm agitation speed. Genetic sequence homology of the most efficient mold isolate showed 100% similarity to Penicillium chrysogenum. High-performance liquid chromatography analysis of phenolic extracts of untreated OMWW showed the presence of five compounds—hydroxytyrosol at 1.22 g.L⁻¹, tyrosol at 0.05 g.L⁻¹, caffeic acid at 0.16 g.L⁻¹, p-coumaric acid at 0.05 g.L⁻¹ and oleuropein at 0.04 g.L⁻¹—that were eliminated during the degradation process at 88.82%. Genotoxicity, assessed by the Vicia-faba root cell, showed a significant decrease in micronucleus frequency of about 96% after fungal treatment. These results confirm the positive role of fungal treatment of OMWW to eliminate genotoxicity and their ability to improve the agronomic potential.

Global antibiotic consumption is increasing dramatically. Antibiotic release into the environment, primarily through wastewater discharge, has serious impacts for human and animal health and microbial ecosystems. To address this issue, white-rot fungi present a promising solution, as they possess oxidative enzymes that can degrade these pollutants. Here we investigated the effectiveness of the white-rot fungus Bjerkandera adusta TM11 for removing three persistent fluoroquinolone antibiotics, i.e. levofloxacin, ciprofloxacin, and enrofloxacin, in real wastewater. The three antibiotics were added to the wastewater separately at a concentration of 30 mg/L and together in a cocktail at 10 mg/L, then incubated for 9 days. LC-MS/MS analysis and anti-microbial assay (against Escherichia coli) demonstrated complete removal of levofloxacin by day 7. However, ciprofloxacin and enrofloxacin biotransformed into degradation products that still had antimicrobial activity, with degradation efficiencies reaching 82 % and 99 %, respectively, by day 7. Proteomic analysis identified 21 fungal heme peroxidases. Versatile peroxidase was the most strongly-produced enzyme potentially involved in antibiotic biotransformation. Degradation products were characterized by LC-MS/MS analysis, and a degradation pathway was proposed based on these findings.