Search Results (106)

Coatings are often applied in the materials industry to impart hydrophobic properties to the produced materials. Commonly used coatings contain plastics as well as perfluorinated compounds, which pose challenges for environmental sustainability due to their persistence and end-of-life impacts. Coatings based on natural wax, such as rapeseed, soy, palm or beeswax, constitute a key bio-based and more sustainable alternative. These waxes exhibit high hydrophobicity while also being biodegradable, offering opportunities to replace fossil-derived coatings within circular-economy material systems. Wax coating constitutes a protective layer that undergoes biodegradation after a certain amount of time. This paper presents the results of studies concerning the development of a wax coating characterized by a coarse microstructure that increases water resistance, and an appropriate susceptibility to biodegradation. It was revealed that all the analysed coatings were susceptible to biodegradation, although their rates varied markedly depending on wax type and form. The biodegradation of palm wax in bulk form and as a thick layer was 17% and 80%, respectively, after 180 days. Palm wax exhibited a pronounced ability to bind inorganic and organic matter deposits, which reduced the degradation rate. When applied as a thin coating, palm wax did not form such a barrier. Palm wax significantly influences coating durability because its surface undergoes morphic changes induced by bio-surfactants secreted by microorganisms. These changes the adhesion of organic and inorganic matter particles, and the layer thus established limits the diffusion of oxygen, enzymes and microorganisms to the wax coating. The tests demonstrated that the addition of palm wax to wax mixtures allows the degradation rate to be controlled, and that its inhibitory effect is strongly dependent on the geometry of the material. Full article

Aquatic species are exposed to several long-chain per- and polyfluoroalkyl substances (PFASs) in the environment but their potential toxicity is not well studied. In this study, we assessed the effects of perfluoroundecanoic acid (PFUnDA) exposure on developing zebrafish. To do this, we investigated the potential for oxidative stress and neurotoxicity by measuring reactive oxygen species, apoptosis, gene expression, and locomotor activity. Mortality was evident in fish exposed to 1000 µg/L PFUnDA, and apoptosis was indicated in fish exposed to 100 µg/L PFUnDA via an increase in casp3 transcription. No change in reactive oxygen species in 7-day-old larval fish exposed to 0.01 up to 1000 µg/L PFUnDA was detected. Visual motor response analysis revealed hypoactivity in different light–dark periods that occurred in a concentration-specific manner. At the transcriptional level, several neurotoxicity-related genes (casp3, bdnf, gfap, gmfb, nkx2-2a) were significantly upregulated, further supporting neurotoxic effects. Overall, these findings indicate that PFUnDA disrupts neurodevelopment and behavior in zebrafish larvae, raising concerns for this long-chain PFAS. Full article

Wastewater treatment plants (WWTPs) can still be considered point sources of contamination into receiving aquatic ecosystems, especially for many emerging contaminants, which require additional treatments for their removal. In this study, the impact of a WWTP on the water quality of a river located in the metropolitan area of Milan, Northern Italy, was investigated. A wide range of emerging contaminants (i.e., perfluorinated compounds, pharmaceuticals, and synthetic fragrances) and traditional contaminants (i.e., heavy metals, nutrients, and microbiological parameters) were analyzed, both in the river water and in the wastewater at the inlet and outlet of the WWTP, with the aim of evaluating removal efficiency and the risk for the riverine ecosystem. The results showed that wastewater treatment acts differently on the analyzed compounds, effectively removing nutrients, bacteria, few pharmaceuticals, and most heavy metals, but leaving others unchanged such as perfluorinated compounds and synthetic fragrances, that are thus discharged into the receiving river, especially during rain events due to the activation of sewer overflows. The calculation of the Risk Quotient for organic compounds confirmed the negative impact of the WWTP effluent on the chemical quality of the river water, with a consequent potential ecological risk for riverine biota. This study also verified that certain traditional contaminants (i.e., total nitrogen (TN), total phosphorous (TP), thermotolerant coliforms, Escherichia coli), and contamination tracer (i.e., chloride (Cl), boron (B), and MBAS (Methylene Blue Active Substances) could be effectively measured in real time rather than through classical laboratory analysis and could support timely risk assessment. Full article

Between 1970 and 2023, China’s yearly anthropogenic CO₂ emissions increased from 0.96 to 13.58 Pg. Yearly non-CO₂ greenhouse gases (GHGs) in China increased from 1133.7 Tg CO₂eq in 1970 to 3095.3 Tg CO₂eq in 2023. In terms of weight of the global warming potential over a horizon of 100 years, China’s anthropogenic non-CO₂ GHG emissions, approximately 56.8%, 13.5%, 10.1%, 10.4%, 5.2%, and 3.9% of which were from methane, nitrous oxide, hydrochlorofluorocarbons, hydrofluorocarbons, perfluorinated compounds, and chlorofluorocarbons, respectively, were equal to 23.3% of its anthropogenic CO₂ emissions in 2023. Despite efforts for mitigation, China’s non-CO₂ emissions are projected to keep growing in the foreseeable future due to unreported emissions, continuous industrialization, and global warming. This result shows that merely controlling anthropogenic CO₂ emissions and achieving carbon neutrality are not enough; non-CO₂ GHG emissions also need to be curbed. Full article

Perfluorinated alkyl substances and polyfluorinated alkyl substances (PFASs) are long-chain compounds, with perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) being the most well-known examples. Both are considered typical non-genotoxic carcinogens (NGTxCs). In this study, we verified whether the Bhas 42 cell transformation assay (Bhas 42 CTA) can be used as an effective in vitro method to predict carcinogenicity of NGTxCs using both PFOA and PFOS as typical representatives. Transcriptome analysis during the PFOA-induced transformation process showed that many factors related to the effects of PFOA on the immune system and cancer hallmarks increased or decreased. Thus, we demonstrated that mechanistic analyses such as transcriptome analyses in combination with the transformation focus formation results from the Bhas 42 CTA may be useful tools when assessing the carcinogenicity and other biological effects of NGTxCs such as PFOA. We propose that the Bhas 42 CTA is a simple in vitro test for the detection of NGTxCs, that it has in vitro oncotransformation as an endpoint, and that it can also detect the activation of factors involved in malignant progression, such as invasion and metastasis. It allows for the comprehensive detection of subtle mechanisms in parallel with focus formation throughout the transformation process, from the early stages to malignancy. Full article

Two cholesterol-based liquid crystalline materials were synthesized by incorporating perfluorinated acyl chains of different lengths with the help of epichlorohydrin and copper(I)-mediated azide-alkyne 2+3 dipolar cycloaddition chemistries. These materials were characterized by differential scanning calorimetry, cross-polarized optical microscopy and powder X-ray diffraction. The compound with the longer perfluorinated chain exhibited a smectic A (SmA) phase as confirmed by XRD and POM, while the shorter-chain derivative exhibited diffraction peaks suggestive of both simple SmA* ordering as well as lamellar solid phase exhibiting multilayer ordering. Full article

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a class of synthetic organic compounds with extremely high chemical stability and environmental persistence that are widely used in the industrial sector and in consumer goods. Their strong C-F bonds make them difficult to degrade, meaning they can migrate through the atmosphere and settle over long distances, posing long-term risks to the global ecological environment and human health. This article systematically reviews the classification, physicochemical properties, concentration levels, spatial distribution, migration and transformation behaviors, and health and ecological impacts of PFASs in the atmosphere, along with related analytical detection techniques and pollution control methods. Studies show that short-chain PFASs are more likely to migrate through the atmosphere due to their high water solubility and volatility, while long-chain PFASs tend to be adsorbed onto particulate matter and display stronger bioaccumulation. Although atmospheric research on PFASs lags behind that focused on their dynamics in water and soil, the existing data still reveal a difference in their distribution and regional pollution characteristics in the gas and particle phases. Toxicological studies have confirmed that PFAS exposure is associated with liver injury, immunosuppression, developmental toxicity, and cancer risk and can threaten ecological security through the food chain. Currently, governance technologies are confronted with the challenges of low efficiency and high cost. In the future, it will be necessary to combine multi-media models, new analytical techniques, and international collaboration to promote the development of source control and innovative governance strategies. Full article

PFASs, compounds to which the C-F bond—the strongest known in nature—bestows high resistance to degradation, have been detected in surface and groundwater worldwide, including drinking water supplies. Current regulations on long-chain PFASs resulted in the shift to short-chain PFASs in industrial uses, with their increasing environmental detection. Currently, suggested BATs for PFAS removal from aqueous solutions include mainly adsorption or membrane filtration; however, different response behavior to even simple treatment was observed concerning long- and short-chain PFAS molecules. In order to permanently destroy (mineralize) PFASs and their precursors, treatment technologies that can deliver sufficiently high energy to crack the C-F bond are needed. This paper discusses current PFAS removal technologies and state of the art advanced methods for PFAS removal and destruction, critically discussing their efficiency, applicability, emerging issues, and future prospects. Full article

This study aimed to evaluate the presence of emerging pollutants [perfluorinated compounds, phthalates and bisphenol A (BPA)] in chinstrap penguins (Pygoscelis antarctica) and krill (Euphausia superba) from Deception Island (South Shetland Islands, Antarctica) to provide data on the occurrence of emerging pollutants in Antarctica. For this purpose, thirty-four samples were studied, including four samples of adult tissue and six samples of chick tissue, as well as krill samples from the area. The selected samples were subjected to extraction processes and subsequent analytical determination of perfluorooctane sulfonate, perfluorooctanoic acid, di(2-ethylhexyl) phthalate, mono(2-ethylhexyl) phthalate and BPA using high-performance liquid chromatography coupled with electrospray ionization mass spectrometry. Our results highlight that the analyzed organic pollutants, except for BPA, are clearly present in Pygoscelis antarctica and Euphausia superba from Deception Island. Full article

Contaminants of emerging concern (CECs), including pharmaceuticals and perfluorinated compounds, pose a growing threat to water quality due to their persistence and resistance to conventional treatment methods. In this context, photocatalytic processes capable of promoting both oxidative and reductive transformations have attracted increasing attention. This study explores the synthesis and performance of a SnS₂-TiO₂ heterojunction photocatalyst, designed to facilitate such reactions under solar and UV-A light. The composite was synthesized via the hydrothermal method and thoroughly characterized for its morphological, structural, surface, and semiconducting properties. The results confirmed the formation of a type-II heterojunction with improved visible-light absorption and suppressed charge recombination. Photoelectrochemical measurements indicated enhanced charge separation and favorable band-edge alignment for reductive processes. Photocatalytic experiments with amoxicillin (AMX) and perfluorooctanoic acid (PFOA) revealed distinct degradation behaviors: AMX was predominantly degraded via superoxide-mediated reductive pathways, whereas PFOA exhibited limited transformation, likely proceeding via a combination of oxidative and reductive mechanisms. While overall removal efficiencies were moderate, this study highlights the role of band structure engineering and heterojunction design in tailoring photocatalytic behavior. The SnS₂-TiO₂ system serves as a promising platform for further development of composite materials to address the challenge of CECs in water treatment. Full article

Per- and polyfluoroalkyl substances (PFAS) are used in consumer products and manufacturing. Perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA) are long-chain PFAS composed of 9, 10, and 11 carbons, respectively, which exert sublethal toxicity to aquatic species. Here, we review the data regarding the environmental fate and ecotoxicology of these understudied long-chain PFAS in fish. The objectives of this study were to (1) compile the literature to compare physiological or molecular signaling pathways disrupted by PFNA, PFDA, or PFUnDA; and (2) uncover potential biomarkers and pathways of toxicity of longer-chain PFAS using gene ontology computational approaches to shed light on their mechanism of action. Studies show that PFAS have a range of effects on fish, including developmental issues, changes in gene expression, and behavioral modifications. Based on our review, PFNA has been studied more frequently in fish compared to PFDA and PFUnDA; however, longer-chained PFAS are proposed to pose greater toxicity. Based on the computational approach, prominent pathways affected by PFNA include insulin signaling [“Insulin -> CEBPA/CTNNB/FOXA/FOXO”, “Insulin -> STAT Expression Targets”], immune system signaling [“TNF -> STAT Expression Targets”, “IL6 Expression Targets”, and “IL2 Expression Targets”], and growth hormone/prolactin signaling [“GH1/PRLR Expression Targets”, “PRL/GHR -> STAT Expression Targets”, “PRL/PRLR Expression Targets”]. Several transcripts related to cholesterol metabolism were also affected by PFNA. This review summarizes the current knowledge on the distribution, fate, and ecotoxicology of PFNA, PFDA, and PFUnDA in teleost fish, highlighting potential physiological and molecular responses that could aid in assessing long-chain PFAS toxicity in future studies. Full article

In recent decades, societies and economies across the globe have started to show signs of stress associated with water shortages. Meeting the sustainability benchmarks in arid and semi-arid regions has caused water reuse to be considered a viable alternate source to augment the existing water supply resources. Water reuse, resource recovery, and recycling are extensions of the concept of a circular economy that has been practiced in other fields. Globally, the U.S. has played a leadership role in the development of guidance and regulations for various water reuse applications. Other countries and organizations have also developed similar programs. This paper aims to propose a review of the existing literature and provide a broader perspective of water reuse focusing on the most pressing issues such as direct potable reuse with the backdrop of viral pathogens and perfluorinated compounds. The global history of statutory developments to regulate the selected contaminants has also been discussed by covering the recent advancement in water reuse applications. Technological developments and regulatory trends are chronicled in the context of emerging contaminants linked with an imminent social, industrial, and agricultural prospectus. The proposed high viral log removal credit for water reuse is a challenging task especially at regular intervals; therefore, the treatment requirements must be verified to ensure public safety. The extreme persistence of PFAS, their tendency for buildup in biotic systems, and their removal is another challenging task which requires development of cost effective and efficient technologies. Disparity in the financial and technological capabilities of regional or internal stakeholders of shared watershed or aquifer is a bottleneck in tangible advancements in this area. The role of public–private partnerships in addressing the impending water sustainability challenges is discussed as a model for future direction in funding, managing, and public acceptance. Full article

This study primarily focuses on the analysis of volatile organic compounds using GC–MS, with ICP-MS employed as a complementary method to quantify trace metal content. Headspace GC–MS was conducted to detect alkylphenol ethoxylates (APEOs), formaldehyde, aromatic amines derived from azo dyes, perfluorinated carboxylic acids, chlorophenols (PCPs), tetrachlorophenols (TPCs), and phthalates in textile samples of different origin and composition. Principal component analysis was used to detect patterns in the volatilome according to the origin and the textile composition. In addition, seven metals (Cr, Ni, Cu, Mo, Cd, Hg, and Pb) were quantified in a subset of samples. The study revealed distinct chemical profiles in textiles based on their origin, with GC–MS identifying key volatile organic compounds and ICP-MS quantifying heavy metals in a subset of samples. Principal component analysis highlighted cotton content as a critical factor in differentiating textile profiles. While most samples adhered to regulatory standards, some exceeded thresholds for metals like copper and nickel, underscoring the need for enhanced quality control in manufacturing processes. By integrating advanced analytical methods, this study provides insights into sustainable and safe textile production, offering valuable benchmarks for regulatory compliance and industry best practices. The outcomes contribute to improving product safety, promoting responsible manufacturing, and supporting regulatory bodies in the enforcement of environmental and safety standards, aligning with the growing demand for sustainability in the textile sector. Full article