Microplastics

Microplastic (MP) pollution is an increasing environmental concern in coastal areas exposed to anthropogenic pressure, although its ecological and human-health implications depend on exposure, bioavailability, and potential effects. This study assesses MP contamination across seven beaches in the Gulf of Gabès, Tunisia, by integrating environmental characterization, polymer identification, and spatial analysis within the context of coastal sustainability. The mean MP abundance was 170.38 ± 17.14 items kg⁻¹ of dry sediment. Microplastics were characterized by shape, color, and size, with fibers and fragments being the most prevalent forms. Fourier-transform infrared spectroscopy (FTIR) identified polyethylene (PE), polypropylene (PP), and polystyrene (PS) among the analyzed particles. Some foam particles exhibited spectral features tentatively consistent with the antioxidant additive Cyanox 53; however, this assignment requires independent analytical confirmation. Spatial variability was explored using the Microplastic Pollution Index (MPPI), the Coefficient of Microplastic Impact (CMPI), hierarchical cluster analysis (HCA), and principal component analysis (PCA). Based on the adopted MPPI classification scheme, five beaches were classified as high, one as very high, and one as moderate. The observed spatial patterns may be associated with local anthropogenic activities, including tourism, fishing, and waste discharge, although these potential sources were not directly investigated. The findings provide baseline information on MP contamination across the surveyed beaches and may inform future monitoring and coastal management initiatives relevant to Sustainable Development Goals 14, 12, and 8. The results should be interpreted in light of the study’s spatial and temporal scope and methodological limitations and should not be considered direct evidence of ecological effects or human-health risks.

Microplastics are now pervasive across environmental compartments, ingested by more than 1500 species, and detected in human tissues, yet policy responses remain fragmented and inadequate. Annual microplastic inputs to the environment are estimated at 10–40 million tonnes and are projected to double by 2040. Most governance has relied on voluntary industry initiatives, consumer behaviour change, recycling campaigns, and narrow restrictions on selected products. There is little evidence that these approaches have materially reduced microplastic pollution, and plastic production and leakage have continued to grow. With negotiations for a global plastics treaty stalled over production controls, national governments can act through existing and emerging regulatory tools. This paper identifies ten priority policy actions that target production volumes, product design standards, and point-source discharge controls rather than downstream capture alone. These priorities span wastewater and stormwater management, regulation of tyres, synthetic textiles, paints, manufactured microplastics and pre-production pellets, elimination of unnecessary single-use plastics, and limits on primary polymer production. Binding legal precedents exist in at least one jurisdiction for most of these priorities, although several have been adopted but are not yet applicable; the final priority, capping primary polymer production, is ambitious but under negotiation. After two decades of research, the sources and pathways of microplastic pollution are clear enough to regulate; what is now needed is the political will to apply the tools already available.

Microplastic (MP) contamination in wastewater is an emerging environmental concern. This study evaluated electrocoagulation (EC) using Al–Al electrodes to remove high-density polyethylene microplastics (HDPE-MP) from synthetic water and real municipal wastewater. A Box–Behnken design coupled with response surface methodology was used to assess the effects of initial pH, current density (J), initial HDPE-MP concentration, and NaCl concentration. In real municipal wastewater, the highest average HDPE-MP removal (88.5%) was achieved at pH 7, together with COD and turbidity reductions of 58.9% and 72.3%, respectively. NaCl concentration had a limited direct effect on HDPE-MP removal. Increasing the nominal current-density level did not proportionally improve removal efficiency, while average energy consumption increased from 9.11 kWh/m³ at the nominal level of 5 mA/cm² to 33.06 kWh/m³ at the nominal level of 20 mA/cm². XRD analysis of the recovered sludge showed poor crystalline Al-based phases and diffraction features consistent with semicrystalline HDPE. Overall, Al–Al electrocoagulation showed promising performance for HDPE-MP removal from complex wastewater matrices, although operating conditions should be optimized to balance removal efficiency and energy consumption.