Environmental Science and Pollution Research最新文献

Microplastics (MPs) have become an emerging contaminant of concern, yet their presence in ocular formulations and products remains poorly understood. This study employed a dual-method approach (water dilution and Fenton digestion) coupled with micro-FTIR analysis to investigate the MP contamination in 21 commercial eyedrop products in Malaysia. Our findings demonstrate widespread contamination, with 81% of samples containing detectable MPs. They are predominantly composed of polystyrene (PS) (52%), polyamide (PA) (19%), and polyethylene (PE) (14%). The particle abundance varied significantly across classes of eyedrops. Specifically, one lubricant eyedrop reported a mean concentration of 3 particles/ml, representing the highest concentration among all categories. Morphological characterization revealed diverse particle shapes, including irregular fragments (most common), fibers, and pellets. The area of MPs detected ranged between 369 to 36,388 µm². The pollution load assessment indicated that the lubricant eyedrops showed extreme contamination levels (MPCF = 15). The calculated daily microplastic exposure (DME) suggests a potential emission of up to 2.704 million MP particles daily among lubricant users in the general Malaysian population. Glaucoma patients in rural areas are potentially exposed to 0.049 million particles daily and urban areas at 0.137 million. These results provide the first evidence of MP contamination in eyedrops in Malaysia, highlighting a previously unrecognized route of human exposure. The findings emphasize the need for improved manufacturing standards and regulatory oversight to minimize plastic contamination in ocular products. While these findings suggest MPs are present in many eyedrop products, further research would be needed to understand any potential health implications.

Simultaneous removal of multiple pollutants from industrial emissions offers significant cost and space savings when upgrading air pollution control devices. Sintering processes emit complex pollutant mixtures including SO_x, NO, volatile organic compounds (VOCs), and dioxins (PCDD/Fs). This study evaluates the simultaneous removal of NO, PCDD/Fs, and toluene using three commercial V₂O₅-MoO₃/TiO₂ (VMT) selective catalytic reduction (SCR) catalysts, under simulated flue gas conditions at 220 °C. The catalysts designated Cat-1, Cat-2, and Cat-3 differed in composition, including variations in MoO₃, V₂O₅, and the addition of SiO₂ or WO₃. The effects of H₂O_(g) and SO₂ were also evaluated to assess catalyst stability and resistance to poisoning. Cat-1, with the highest MoO₃ content, achieved the best overall performance with removal efficiencies of 93.1% for PCDD/Fs, 83.3% for NO, and 84.6% for toluene. Cat-2, containing sulfur-resistant SiO₂ and WO₃, demonstrated superior NO and PCDD/Fs removal in the presence of H₂O_(g) and SO₂. Cat-3, with the highest V₂O₅ content, exhibited the highest NO conversion when H₂O_(g) and SO₂ were absent, and its performance was minimally affected by co-pollutants. This work confirms the efficacy of VMT catalysts for multipollutant control, highlighting their potential for industrial applications.

The recycling of spent lithium-ion batteries (LIBs) has gained extensive interest due to its simultaneous environmental and resource-saving benefits. Although using strong corrosive acids to recover critical metals from wasted LIBs is now the favoured method, the excessive use of chemical reagents can pose major environmental problems. In this paper, the use of greener reagents for the treatment of cathodic material coming from lithium-cobalt oxide (LCO) and nickel-manganese-cobalt (NMC) batteries was investigated; specifically, leaching with organic acids such as acetic acid, citric acid, and formic acid was innovatively studied. The auspicious results showed that 90% of LCO and 84% of NMC cathodic materials were leached after 60 min of treatment using formic and citric acid, respectively. Subsequently, chemical precipitation of the metals was performed by increasing the pH and adding sulfides, allowing for the recovery of almost 99% of cobalt and 100% of cobalt, nickel, and manganese previously leached from LCO and NMC cathode materials, respectively. Based on the experimental investigation, it was proven that the proposed innovative process is suitable for recovering valuable metals contained in LCO and NMC batteries without generating toxic wastewater or introducing hazardous chemicals. Thus, the suggested method may provide efficient cobalt, nickel, and manganese recovery from wasted LIBs while eliminating possible environmental and human health risks.

Air pollution caused by particulate matter (PM) originating from road traffic poses a serious threat to the health of urban residents. Concentration levels depend on meteorological conditions, microclimatic parameters affecting dispersion, the influence of individual emission sources, local orographic and urban factors, as well as chemical transformation processes. The aim of the study was to determine the relationship between road traffic intensity (vehicles/hour) and particle number concentrations of accumulation mode and coarse mode particles in the 0.3-10 µm size range (hereafter referred to as PNC_0.3-10), along with an assessment of statistical associations between traffic intensity and particle number concentrations. Achieving this objective required a quantitative evaluation of the main factors influencing PNC_0.3-10 measurements, particularly the contribution of road traffic. The results indicated that meteorological conditions, specifically wind speed and mixing layer height, were the most significant variables affecting PNC_0.3-10 levels, regardless of particle size range. Therefore, it was necessary to consider how to remove the influence of these dominant factors from the PNC_0.3-10 measurements. To this end, a modified meteorological normalization method was applied, allowing for the removal of both meteorological influences and other emission sources from the PNC_0.3-10 time series. A strong statistical association was observed between traffic intensity and normalized PNC_0.3-10 (nPNC_0.3-10) for particle fractions larger than 2.5 µm (r_Spearman > 0.85, adj. R² > 0.63). In contrast, no linear relationship was found for fractions in the range of 0.3 µm to 2.5 µm (r_Spearman < 0.46, adj. R² < 0.15). These results should be interpreted as empirical statistical relationships rather than direct evidence of linear emission mechanisms.

Plastic debris entanglement is a significant threat to avian populations. While primarily reported in marine species, terrestrial birds inhabiting urban environments are increasingly exposed to anthropogenic materials. We studied mortality and injury in the Eurasian tree sparrow (Passer montanus) resulting from the incorporation of plastic debris into nests across an urbanization gradient near Gwangju, Republic of Korea. We quantified urbanization based on building, paved road, and vegetation cover using semi-automated image processing. All 38 nests surveyed across 11 roof-tiled houses contained anthropogenic materials, constituting an average of 13.6% (6.51 ± 5.31 g) of the total dry nest weight. Linear materials, particularly plastic line, were the most prevalent type, used mainly in the outer wall of the nest. We documented a total of seven carcasses (both juvenile and adult) and three live nestlings entangled with this material. Entanglement primarily occurred around the legs, wings, and/or neck, leading to death for the deceased individuals and injury for the surviving nestlings. The higher the urbanization score, the greater the dry weight of anthropogenic material within the nest. Although the live nestlings were rescued and successfully fledged, the high incidence of mortality indicates that a severe ecological trap is created by the widespread availability and use of linear plastic debris as nesting material. These findings highlight a need for increased conservation focus on the entanglement risk posed by plastic debris to common, urban-adapted terrestrial bird species.

Phytoremediation using native macrophytes offers a sustainable approach to improving domestic wastewater (DW) quality while promoting ecological balance. This study evaluated the phytoremediation potential of Schoenoplectus americanus (Pers.) Volkart ex Schinz and R. Keller under mesocosm-scale conditions simulating real environmental settings. The removal efficiency of key physical, chemical, microbiological, and organoleptic parameters was assessed, alongside the plant's physiological, biochemical, and metabolomic responses. After 30 days of treatment, S. americanus achieved significant reductions in contaminants, including 97% of total phosphorus, 85% of chemical oxygen demand, 82.5% of total nitrogen, and near-complete removal of total coliforms (from 2 × 10⁶ to 7 × 10² NMP/mL) and mesophilic aerobic bacteria (from 3 × 10⁶ to 4 × 10³ UFC/mL). Moreover, the treated water exhibited clear improvements in odor and color. Physiological analyses revealed stable osmotic potential and membrane permeability, while increases in photosynthetic pigments, primary metabolites, and abscisic acid levels indicated adaptive responses to abiotic stress conditions. Gas chromatography-mass spectrometry analysis identified secondary metabolites, such as 13-docosenamide, potentially involved in enhancing plant-microbe interactions and nitrogen metabolism. Overall, S. americanus demonstrated high resilience and efficiency in DW treatment, supporting its integration into nature-based treatment solutions such as floating wetlands. These systems represent a sustainable and scalable approach with clear applicability to real-world wastewater treatment, particularly in settings lacking conventional infrastructure.

The extensive use of synthetic sorbents in oil spill remediation is increasingly constrained by economic costs and adverse environmental impacts. Consequently, the development of sustainable, bio-based sorbent materials has become a priority in environmental protection research. This study critically evaluates the applicability of dried Posidonia oceanica leaves as a natural sorbent for crude oil removal from the water surface under batch wet conditions. The influence of key operational parameters including contact time, sorbent particle size, crude oil film thickness, and sorbent dosage on adsorption performance was systematically investigated. Structural and surface characteristics of the raw and oil-loaded sorbents were examined. FTIR confirmed crude oil uptake through the appearance/intensification of hydrocarbon functional-group signatures on the biomass matrix, while SEM showed that the initially rough, porous surface became largely covered by a continuous oil-rich layer with adhered oil droplets. The results demonstrated rapid adsorption kinetics, with equilibrium achieved within 5 min. Adsorption capacity was strongly dependent on particle size and oil film thickness. A maximum crude oil adsorption capacity of 5.02 g/g dry sorbent was attained at 25 °C. The findings indicate that dried Posidonia oceanica leaves exhibit significant potential as an eco-friendly, biodegradable, and efficient biosorbent for crude oil spill remediation in marine environments.

Environmental toxicity from metal/metalloid pollution threatens the sustainability of crop species by impeding growth and yield. The acquisition of toxic elements (TEs) is manifested in tissues mostly through water relations and oxidative stress. Tolerant species can thrive through chelation, sequestration, and induction of antioxidative genes. The cellular-level regulations are controlled by non-coding small RNAs, microRNAs (miRNAs), which induce gene silencing and cause metal toxicity. With the advent of next-generation sequencing (NGS), miRNAs play a role in interpreting TE sensitivity via signaling pathways for stress tolerance. Recently, NGS technologies have identified more miRNAs with various roles in TEs. The regulation targets post-transcriptional modification following translational inhibition of specific genes. With another regulatory web, miRNAs are associated with genes concerned with transcription factors (TFs), membrane transporters, chaperons, growth regulators, signaling residues, etc. The redox balance in sensitive tissues, linking metabolic cycles and biogenesis, is influenced by feedback regulation of oxidative stress. Epigenetic alterations, including DNA methylation, following post-translational modification of regulatory proteins, play roles in modulating tolerance to TEs. The identified miRNAs synchronize signaling pathways that regulate cellular turgidity, the integrity of wall proteins, ion trafficking or sequestration, redox equilibrium, and metal transporter-like functions. Moreover, miRNA target sequences encoding TFs imply the involvement of major metabolic flux in the regulation of biogenesis for tolerance to TEs. In this review, we highlighted TE-mediated miRNA regulation and their associated roles in oxidative stress, signaling pathways, and coordinated physiological responses to TEs in plants.

Lichen transplants are effective tools used to biomonitor airborne potentially toxic elements (PTEs) in urban and natural areas. The main objective of this study was to measure atmospheric PTE concentrations during the dry period in the urban and mountainous areas of Chiang Mai Province using lichen transplants. Samples of the lichen Parmotrema tinctorum (Despr. ex Nyl.) Hale were collected from a remote area and exposed at 18 sites in the Chiang Mai urban area and Doi Suthep-Pui National Park for 120 days. The concentrations of 15 PTEs, including Al, As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Ti, V, and Zn, in the lichen transplants were determined using inductively coupled plasma-mass spectrometry (ICP-MS). The results revealed that the average PTE concentrations and pollution load indices (PLIs) presented the highest values in the urban area, followed by the mountain road and forested areas. Most monitoring sites were classified as having very high pollution, and these sites were observed in all areas. This indicates that the air of some locations in the national park, including forested areas, could be contaminated by the investigated PTEs. The contamination factor (CF) values suggested that Pb, Co, Cr, Cd and Ni highly contaminate the air. These elements can originate from various sources, especially motor vehicles and biomass burning. The results of this study can be used as complementary data to traditional air quality monitoring programs to improve environmental quality in Chiang Mai Province.