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In the framework of sustainability, proposing new technologies to improve the current linear economy system is one of the most challenging aspects for both academics and industries. In this context, the optimization of wastewater recovery and re-use are among the most crucial aspects to improve; in fact, contaminated waters come from a wide range of industries: cooking, refineries, food, pharmaceuticals, textile and agriculture. Heavy metals are among the most critical pollutants, being widely spread (especially in the textile sector) and difficult to remove. In this work, two different sets of Magnetic Nanostructured Adsorbents (MNAs) to clean wastewaters containing Chromium (III), Nickel (II) and Copper (II) ions were studied and compared. The first type of MNA was a 2-D nanosheet structure generated using iron (II/III) salts and sodium (or ammonium) hydroxide solution to decorate a dispersion of graphene oxide (GO) in water. The second type of adsorbent was a 3-D structure composed of GO-MNAs embedded in cross-linked alginate beads. Performed experiments (in a wide range of metal ions concentrations) showed very promising results in terms of removal efficiencies (almost complete abatement could be achieved using a proper amount of MNAs) with respect to all tested contaminants, highlighting better performances of the beads with respect to the corresponding 2-D structure.

Environmental pollutants are claimed to be major factors involved in the progressive decline of the fertility rate worldwide. Exposure to the heavy metal Cadmium (Cd) has been associated with reproductive toxicity due to its ionic mimicry. However, the possible direct accumulation of Cd in human sperm cells has been poorly investigated. In this study, we aimed to clarify the possible direct effect of Cd exposure on sperm function through the analysis of its cell accumulation. Semen samples from 30 male subjects residing in high environmental impact areas and adhering to the “Exposoma e Plurifocalità nella Prevenzione Oncologica” campaign for testis cancer prevention were compared with semen samples from 15 males residing in low exposure areas. Semen levels and cell Cd content were quantified by inductively coupled plasma (ICP) spectroscopy. Cell Cd distribution was assessed by scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS). The impact of Cd on sperm function was evaluated by the in vitro exposure to the heavy metal, whilst possible scavenging approaches/agents were assessed. In addition to higher values of semen Cd, exposed subjects showed a reduction in total motile sperm fraction compared to not-exposed controls (59.6% ± 13.6% vs. 66.3% ± 7.3%, p = 0.037). Semen Cd levels were also significantly correlated with SEM-EDS signals of Cd detected on the head and neck of sperm (respectively p = 0.738, p < 0.001 and ρ = 0.465, p < 0.001). A total of 2 h of in vitro exposure to 0.5 μM Cd was associated with a significant reduction of sperm progressive motility. Scavenging approaches with either hypo-osmotic swelling or 10 μM reduced glutathione were ineffective in blunting cell Cd and restoring motility. The reduction of exposure levels appears to be the main approach to reducing the reproductive issues associated with Cd.

Water is a vital source for both human life and environment, with 10% of the water globally available for domestic use. World Health Organization and UNICEF mention, in a report on Progress on Sanitation and Drinking Water, that approximately 768 million people do not have access to clean water, and companies are working for finding and implementing circular economies in order to save water for a sustainable production. In this context, the optimization of wastewaters recovery and their recycling are among the most crucial aspects to improve. Industrial wastewater can be also a resource for recovering valuable materials and components and, when properly purified, can be almost entirely recycled, setting the basis for a circular economy from the water re-use point of view. In recent years, environmental remediation research studies have been focused on the design and development of nanosized materials for adsorption of both organic and heavy metal pollutants. Their small dimension on one side allows for a low resistance to mixing but it also represents a limit for their final separation from the aqueous mixture, potentially becoming additional pollutants. In this study, a new set of selective magnetized nanoadsorbents/nanoparticles (MNPs), potentially capable of removing a wide series of pollutants (both organic and inorganic) from wastewaters, have been developed and tested at lab scale.