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Microplastic particles (MPs) are widely distributed pollutants in the environment. While a growing number of studies have shown that MPs are toxic to plant and animal life, systemic efforts to reduce their presence have been scarce. Low-density polyethylene (LDPE) and polystyrene (PS) are one of the most common among all plastic-forming MPs. In this study, pure bacterial strains, Bacillus licheniformis and Lysinibacillus massiliensis, and a mixed bacterial culture of Delftia acidovorans and Bacillus sp., were used for biodegradation of LDPE and PS microplastics. Biodegradation of MP-PS and MP-LDPE of particle size 300 - 500 µm was carried out under batch operating conditions at a temperature of 25 ± 2 °C, pH values of 7.15, and 160 rpm during 22 days. The obtained results showed that mixed bacterial cultures degraded MP-LDPE and MP-PS better than pure bacterial cultures, and the biodegradation efficiency was higher for MPLDPE than for MP-PS, as indicated by greater reduction in peak intensity and spectral deformation, higher colony forming unit (CFU), and inorganic carbon (IC) values. [ABSTRACT FROM AUTHOR]

This review has four major objectives: I) to present the problem of phthalate pollution, II) to highlight common techniques for quantification of phthalate compounds in water, III) to summarize current trends in determination of phthalates toxicity and point out the major adverse effects, and IV) to discuss and critically compare modern approaches in purification of phthalate-polluted water samples and thus reveal the further perspectives. Phthalates are organic compounds that are used extensively as additives in plastics and personal care products. They have high leaching potential and, therefore, they have been detected in various environments, including aquatic environments. Concentrations of phthalates in water are generally low, so their determination usually requires preconcentration. However, phthalates are compounds with very high hazardous potential. Related toxicity studies have been focused mainly on long-term exposures, and the results have shown that phthalates mainly affect the endocrine and reproductive systems. Therefore, phthalates have become a global concern. Their removal from the environment not only ensures environmental protection, but the protection of human health as well. Among various presented approaches for phthalates removal, anaerobic biodegradation has shown the highest potential for further developments because it is a promising technology for using wastewater as a source of green energy. [ABSTRACT FROM AUTHOR]

The environmental impact of plastic waste is a growing global challenge, primarily due to non-biodegradable plastics from fossil resources that accumulate in ecosystems. Biodegradable polymers like polyhydroxyalkanoates (PHAs) offer a sustainable alternative. PHAs are microbial biopolymers produced by microorganisms using renewable substrates, including agro-industrial byproducts, making them eco-friendly and cost-effective. This study focused on the isolation and characterization of PHA-producing microorganisms from agro-industrial waste, including chickpeas, chickpeas with bean residues, and starch. Screening via Sudan Black staining identified PHA-accumulating strains such as Brevibacillus sp., Micrococcus spp., and Candida krusei , among others. To assess the potential for PHA biosynthesis, solid-state fermentation (SSF) was conducted using agro-industrial waste as substrates, along with a mixed culture of the isolated microorganisms. The highest observed yield was a PHA accumulation of 13.81%, achieved with chickpeas containing bean residues. Structural and thermal characterization of the PHAs was performed using Fourier-transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). FTIR-ATR spectra indicated polyhydroxybutyrate (PHB), suggesting it as the synthesized PHA type. This study highlights the potential of agro-industrial waste for sustainable PHA production and eco-friendly bioplastics.

In the process of paper recycling, certain amounts of metals can be found in the cellulose suspension, the source of which is mainly printing inks. The paper industry often uses different technologies to reduce heavy metal emissions. The recycling of laminated packaging contributes to the formation of sticky particles, which affects the concentration of heavy metals. This study aimed to determine the mass fraction of metals in the different phases of the deinking process to optimize the cellulose pulp's quality and design healthy correct packaging products. In this research, the deinking flotation of laminated and non-laminated samples was carried out by the Ingede 11 method. As a result of the study, the mass fractions of metals in cellulose pulp were divided into four groups according to the mass fraction's increasing value and the metals' increasing electronegativity. The quantities of metals were analyzed using Inductively Coupled Mass Spectrometry (ICP-MS). The separation of metals from cellulose pulp is influenced by the presence of adhesives and the electronegativity of the metal. The results of the study show that the recycling process removes certain heavy metals very well, which indicates the good recycling potential of pharmaceutical cardboard samples.