Environmental Technology & Innovation最新文献

Textile effluents constitute a significant source of environmental contamination due to the substantial discharge of recalcitrant azo dyes. These synthetic xenobiotic compounds, extensively employed across various industries, represent a predominant class of colorants. The persistence of azo dyes in aquatic ecosystems poses a formidable threat to biota, encompassing flora, fauna, and anthropogenic populations. These recalcitrant pollutants can infiltrate agricultural systems through irrigation practices, facilitating their entry into trophic networks and eliciting deleterious effects on human health. Conventional physico-chemical treatment methodologies have been implemented for the remediation of dye-laden wastewater; however, the inherent stability and color-fastness of azo dyes render the decolorization process arduous. Stringent environmental regulations have been promulgated to mitigate the discharge of these hazardous compounds into aquatic systems. Bioremediation emerges as a promising solution for the effective treatment of toxic synthetic dyes. This review elucidates biological decolorization technologies for azo dyes exhibiting carcinogenic, mutagenic, and phytotoxic properties. It explores microbial biodecolorization mechanisms, emphasizing the roles of bacteria, fungi, and algae, and their enzymes in the adsorption and degradation of dye molecules, facilitating their complete mineralization into innocuous entities. Strategies to enhance biodecolorization efficiencies, such as sequential aerobic-anaerobic decolorization and immobilization techniques, are also discussed. Immobilization of biological decolorizers enables their long-term efficient utilization. Various technologically advanced interdisciplinary approaches to mitigate azo dye problems have also been covered. This comprehensive review aims to guide researchers and environmentalists in devising effective treatment modalities for toxic dye remediation and environmental conservation.

Despite increasing debates about their potential side effects on human health, data concerning the risks and the impacts associated with pesticides remains scarce. Analytical tools allowing the measurement of most pesticides and/or their metabolites to which the population can be exposed are also of need. In the present study, the limits of detection (LODs) of 3 different screening procedures based on either Low-Resolution and High-Resolution Mass Spectrometry (LR-MS and HR-MS) for the determination of pesticides in serum (among which carbamates, dithiocarbamates, neonicotinoids, organochlorines, organophosphates and pyrethroids) were explored. For HR-MS, a quadrupole time-of-flight was used in positive and negative electrospray ionization modes and data were obtained from either a targeted scheduled MSMS acquisition (HR-MSMS) or a data-independent acquisition (HR-DIA). For LR-MS, a triple quadrupole was used and data were acquired with a classical multiple-reaction monitoring (MRM) mode. Depending on the approach, the LOD values varied from 0.05 to 10 ng/mL. For the lowest concentrations, the proportion of molecules detected was systematically greater for the LR-MS approach, while those of HR-MSMS were better than those of HR-DIA. These differences in the LOD values were confirmed in a sample of 174 serums in which LR-MRM detected 89 compounds while HR-MSMS and HR-DIA detected 79 and 75 compounds, respectively. Nevertheless, for environmental and occupational purposes, HRMS approach could probably be efficient to detect most of pesticides and their metabolites in human serum and could be suitable for human biomonitoring studies or fundamental research exploring the impact of exposure to pesticides on human health.

A novel polyfunctional group-modified poly(hydroxyethyl methacrylate) polymer, termed PFG-PHEMA, was synthesized for adsorption of Cu²⁺ and Cd²⁺. Material characterization confirmed that the surface functional groups facilitated efficient adsorption of these ions. pH optimization experiments demonstrated that the adsorption capacities of Cu²⁺ and Cd²⁺, reaching 162.2 and 150.3 mg·L⁻¹ respectively, were maximized at a pH of 5, with an initial heavy metal concentration of 200 mg·L⁻¹. Kinetic and isotherm studies indicated that the adsorption process conformed to a monolayer, homogeneous, and chemisorption model, achieving equilibrium within 60 min. The maximum adsorption capacities were determined to be 500 mg·g⁻¹ for Cu²⁺ and 384.6 mg·g⁻¹ for Cd²⁺. Competitive adsorption experiments showed that PFG-PHEMA exhibited superior selectivity for Cu²⁺ over other metal ions. This selectivity was corroborated by X-ray photoelectron spectroscopy (XPS) analysis, which identified the sulfhydryl group as the crucial functional moiety responsible for Cu²⁺ selectivity. Furthermore, the presence of low concentrations of fulvic acid (FA) enhanced adsorption via ternary complex formation, whereas higher concentrations impeded adsorption by forming FA-metal complexes that competed with the polymer. Overall, the strategic incorporation of multiple functional groups into PFG-PHEMA conferred a high adsorption capacity for Cu²⁺ and Cd²⁺. The analysis further indicated that sulfhydryl groups exhibit high selectivity toward Cu²⁺, whereas amine and oxygen-containing groups preferentially bind to Cd²⁺, reinforcing the potential of PFG-PHEMA as a highly effective adsorbent for heavy metals.