Fluoride (F) is an emerging pollutant that originates from multiple sources and adversely affects plant growth and nutrient bioavailability in soil. This greenhouse study investigated the effects of soil F (0, 10, 20, 50, 100, 200 mg kg⁻¹) on morpho-physiological growth characteristics of wheat, soil F contents, and bioavailability and uptake of F, phosphorus (P), sulphur (S), potassium (K), calcium (Ca), magnesium (Mg), aluminium (Al), iron (Fe), manganese (Mn), silicon (Si) and zinc (Zn) by wheat. Higher F significantly reduced plant height and number of leaves particularly at early growth stages and increased visible leaf injury index. Powdery mildew infestation coincided with leafy injury and was higher in elevated soil F treatments. Fluoride treatments (>50 mg kg⁻¹) significantly increased water (H₂O)- and calcium chloride (CaCl₂)-extractable F contents in soil. Water-extractable soil F contents from soil in all concentration were higher than CaCl₂-extractable F. This increased F bioavailability resulted in significantly higher F uptake and accumulation in live leaves, dead leaves and grains of wheat which followed order: live leaves > dead leaves > grains. Leaf injury index and number of dead leaves correlated significantly positively with soil H₂O- and CaCl₂-extractable F contents. Patterns of nutrient (P, K, S) and trace metals (Al, Ca, Mg, Fe, Mn, Si, Zn) varied significantly with F concentrations and between live and dead leaves, and grains except for Zn. Dead leaves generally had higher nutrients and trace metals than live leaves and grains. Fluoride contents in live leaves, dead leaves and grains showed positive correlations with nutrient elements but negative with trace metals. Number of dead leaves correlated negatively with Al, Ca, Fe, Mg, S and Si but positively with P and Zn contents in dead leaves whereas leaf injury index showed positive correlation with Fe, K, P, Si, Zn, S but negative with Al, Ca and Mg contents. These observations provided evidence of higher F uptake and associated impairment in nutrient and trace metal accumulation which caused leaf injury accompanied by powdery mildew infestation in wheat. However, further research in the region is required to confirm the relationship between F pollution, leaf injury and trace metal accumulation in crops under field conditions.

As non-biological molecules, molecular imprinted polymers (MIPs) can be made as antibody mimics for the development of luminescence sensors for various targets. The combination of MIPs with nanomaterials is further recognized as a useful option to improve the sensitivity of luminescence sensors. In this work, the recent progresses made in the fabrication of fluorescence, phosphorescence, chemiluminescence, and electrochemiluminescence sensors based on such combination have been reviewed with emphasis on the detection of pesticides/herbicides. Accordingly, the materials that are most feasible for the detection of such targets are recommended based on the MIP technologies.

PM₂.₅ (fine particulate matter with aerodynamics diameter <2.5 μm) is the most important component of air pollutants, and has a significant impact on the atmospheric environment and human health. Using satellite remote sensing aerosol optical depth (AOD) to explore the hourly ground PM₂.₅ distribution is very helpful for PM₂.₅ pollution control. In this study, Himawari-8 AOD, meteorological factors, geographic information, and a new deep forest model were used to construct an AOD-PM₂.₅ estimation model in China. Hourly cross-validation results indicated that estimated PM₂.₅ values were consistent with the site observation values, with an R² range of 0.82–0.91 and root mean square error (RMSE) of 8.79–14.72 μg/m³, among which the model performance reached the optimum value between 13:00 and 15:00 Beijing time (R² > 0.9). Analysis of the correlation coefficient between important features and PM₂.₅ showed that the model performance was related to AOD and affected by meteorological factors, particularly the boundary layer height. Deep forest can detect diurnal variations in pollutant concentrations, which were higher in the morning, peaked at 10:00–11:00, and then began to decline. High-resolution PM₂.₅ concentrations derived from the deep forest model revealed that some cities in China are seriously polluted, such as Xi ‘an, Wuhan, and Chengdu. Our model can also capture the direction of PM₂.₅, which conforms to the wind field. The results indicated that due to the combined effect of wind and mountains, some areas in China experience PM₂.₅ pollution accumulation during spring and winter. We need to be vigilant because these areas with high PM₂.₅ concentrations typically occur near cities.

Legacy halogenated organic pollutants, including organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), remain ubiquitous in the environment and continue to pose potential (eco-)toxicological threats because of their ongoing releases from land-based sources. This study investigated the spatial trends of freely dissolved PCBs and OCPs by polyethylene passive samplers, and provided evidence of their land-use-based sources and ecological risk in an urbanized estuary area of Narragansett Bay. Dissolved Σ₂₉PCB concentrations ranged from 0.01 to 1.37 ng L⁻¹, and exhibited higher concentrations in the upper, more urban/built-up watershed, and in north coastal areas. Major inputs of PCBs were urban stormwater or treated wastewater that might carry past releases of Aroclors, pigment manufacturing byproducts, and volatilization-associated PCBs from ageing buildings from the Narragansett watershed to the bay. The dioxin toxicity equivalent values of Σ₅PCBs were 8.6E-03 pg L⁻¹ in water. Dissolved OCP concentrations had similar spatial trends to PCBs and were dominated by DDTs (average 230 pg L⁻¹), followed by chlordanes (average 230 pg L⁻¹), and HCB (average 22 pg L⁻¹). Secondary sources of past usage and historic contamination were expected to re-enter the surface water via atmospheric transport and deposition. The risk quotients of DDE, DDD, DDT and α-Endosulfane showed medium to high ecological risks in the northern area, while chlordane, HCB, oxychlordane, and heptachlor epoxide showed low to negligible risks in all zones. This study presented new insights into the presence, sources and transport of legacy halogenated organic contaminants in an urban estuary's watershed by combining passive samplers and geographic information system (GIS) technology. The approach is promising and could be extended to get better understand of terrestrial pollutant mobilization into estuaries affected by anthropogenic activities.

The cement industry is the second largest source of anthropogenic mercury (Hg) emissions in Europe, accounting for 11% of global anthropogenic Hg emissions. The main objective of this study was to examine the influence of Hg emissions from the Salonit Anhovo cement plant on Hg levels measured in the ambient air at Vodarna, 1 km downwind from the flue gas chimney. The findings reveal that the plant raw mill operational status plays an important role in Hg concentrations in the flue gas emitted from the plant. Emitted total gaseous mercury was, on average, higher (49.4 μg/m³) when raw mills were in the direct mode (both raw mills-off) and lower (23.4 μg/m³) in the combined mode (both raw mills-on). The average Hg concentrations in Vodarna were 3.14 ng/m³ for gaseous elemental mercury, 53.7 pg/m³ for gaseous oxidised mercury, and 41.9 pg/m³ for particulate bound mercury for the whole measurement period. Atmospheric Hg speciation in Vodarna, coupled with plant emissions and wind data, has revealed that the total gaseous mercury emitted from the cement plant is clearly related to all Hg species measured in Vodarna. Wind blowing from the northeastern quadrant (mostly NE, ENE) is responsible for the elevated Hg levels in Vodarna, where gaseous oxidised mercury levels are highly linked to the cement plant emissions. However, elevated levels of Hg species in the absence of northeastern winds indicate potential inputs from other unknown local sources as well as inputs from regional and global transport mechanisms.

Global change, including urbanisation, threatens many of the >1400 bat species. Nevertheless, certain areas within highly urbanised cities may be suitable to harbour bat populations. Thus, managing urban habitats could contribute to bat conservation. Here, we wanted to establish evidence-based recommendations on how to improve urban spaces for the protection of bats. In a team effort with >200 citizen scientists, we recorded bat vocalisations up to six times over the course of 2 years at each of 600 predefined sites in the Berlin metropolitan area. For each species we identified the preferred and non-preferred landscape features. Our results show that artificial light at night (ALAN) had a negative impact on all species. For soprano pipistrelles and mouse-eared bats ALAN had the largest effect sizes among all environmental predictors. Canopy cover and open water were especially important for bat species that forage along vegetation edges and for trawling bats, respectively. Occurrence probability of species foraging in open space decreased with increasing distance to water bodies. On a larger scale, impervious surfaces tended to have positive effects on some species that are specialised on foraging along edge structures. Our study constitutes an important contribution to the growing body of literature showing that despite the many negative impacts of urbanisation on wildlife, urban environments can harbour bat populations if certain conditions are met, such as access to vegetation and water bodies and low levels of ALAN. Our findings are of high relevance for urban planners and conservationists, as they allow inferences on how to manage urban spaces in a bat-friendly way. We recommend limiting ALAN to the minimum necessary and maintaining and creating uninterrupted vegetated corridors between areas with high levels of canopy cover and water bodies, in which ALAN should be entirely avoided.

Dufulin is a biologically derived antiviral agent chemically synthesized by α-phosphoramidate in sheep and is effective against viral diseases in plants such as tobacco, rice, cucumber and tomato. However, the environmental behaviors and fate of Dufulin under different cultivation systems remain unknown. This study investigates the absorption, translocation and accumulation of ¹⁴C-Dufulin stereoisomers introduced by pesticide leaf daubing and by mixing the pesticide with soil in different tissues of cherry radish. We particularly focused on whether the behaviors of Dufulin enantiomers in plants were stereoselective. In the leaf uptake experiments, S-Dufulin and R-Dufulin were transported both up and down, while more than 93% of the pesticide remained in the labeled leaves. During the radicular absorption experiments, both enantiomers of Dufulin were taken up by radish roots and moved to the upper part of the plant, while less than 0.2% Dufulin was absorbed from the soil. Hence, it was easier for Dufulin to enter plants through the leaf surface than through the roots. However, we found in this trial that the stereoisomers of Dufulin underwent nonstereoselective absorption and translocation, which implies that rac-Dufulin and its metabolites should be a major research priority. Overall, our results provide a relatively accurate prediction of the risk assessment of Dufulin, which will help guide its rational use in the environment as well as ensure eco-environmental safety and human health.

3D hierarchical porous biochar (HPBC) was synthesized by a thermally removable template without post-activation. Zn(NO₃)₂ decomposition produced gases and ZnO in situ to activate and expand the three-dimensional micro-and mesopores. Compared with pristine biochar (BC), the specific surface area and pore volume of HPBC were increased by 223 and 75 times, respectively. The abundant pore structure of HPBC significantly enhanced the diffusion rate of heavy metals. For example, compared to BC, the time required for HPBC to adsorb Pb²⁺ reach adsorption equilibrium was reduced by 87.5% (40 min vs 5min). Such an adsorption performance of HPBC was also insensitive to different background ions (K⁺, Na⁺, Ca²⁺, and Mg²⁺) with a much higher concentration than that of heavy metals. When applied to treat desulfurization wastewater from power plants, HPBC yielded 100% removal of Pb²⁺ and Cd²⁺, much higher than that by using commercial activated carbon (28%). Molecular dynamics simulation revealed different locations preferred by the adsorption of Pb²⁺ (micropores) and Cd²⁺ (mesopores) in the hierarchical pore structures. The adsorption of Pb²⁺ and Cd²⁺ on HPBC was mainly achieved by diffusion, oxygen functional group complexation, and precipitation. These results provided better knowledge to understand the microscopic adsorption mechanisms of heavy metals in hierarchical pores and a facile yet robust strategy to design such structures in biochar for efficient wastewater treatment.

Catalytic pyrolysis is a promising chemical recycling technology to supplement mechanical recycling since plastics can be broken down into monomers or converted to the required fuels and chemicals. In this study, a microwave (MW) -responsive SiC foam@zeoltie core-shell structured catalyst was proposed for the catalytic pyrolysis of polyolefins. Under microwave irradiation, the SiC foam core works as both microwave adsorber and catalyst support, thus concentrating the generated heat energy on the ZSM-5 zeolite shell, where the catalytic reaction takes place. SiC foam with an open cellular structure can also improve the global transport of mass and heat during plastics pyrolysis. In this work, the effects of the SiO₂/Al₂O₃ ratio and alkaline treatment of ZSM-5 zeolite coated SiC foam under MW irradiation on the variations in product distribution from low-density polyethylene (LDPE) pyrolysis were investigated at 450 °C. The results indicated that the appropriate acidity and pore structure were crucial to upgrading gas and liquid products. Particularly, the creation of a mesoporous structure in ZSM-5 zeolite via alkaline treatment could improve the diffusion of large molecules and products, thus significantly increasing the selectivity of high-valued light olefins and aromatics while inhibiting the formation of unwanted alkanes, which are expected in the chemical industry. Concretely, the concentration of olefins in gas increased to 51.0 vol% for ZSM-5(50)-0.25AT, and 65.6 vol% for ZSM-5 (50)-0.50AT, compared with 45.2 vol% for the parent ZSM-5(50). The relative concentration of aromatics in liquid decreased from 96.6% for ZSM-5(50) to 75.9% for ZSM-5(50)-0.25AT, and 71.1% for ZSM-5(50)-0.50AT. Given the respective yield of gas and liquid, the total selectivity of C2–C4 olefins and aromatics for mesoporous ZSM-5 zeolites could reach 58.6–64.9% during LDPE pyrolysis, which were higher than that for the parent ZSM-5 zeolite.

In this study, we firstly used alginate to enhance an electrokinetic technology to remediate soil contaminated with divalent heavy metals (Pb²⁺, Cu²⁺, Zn²⁺). The mechanisms of alginate-associated migration of metal ions in electric field were confirmed. Alginate resulted in a high electrical current during electrokinetic process, and soil conductivity also increased after remediation. Obvious changes in both electroosmotic flow and soil pH were observed. Moreover, these factors were affected by increasing alginate dosage. The highest Cu (95.82%) and Zn (97.33%) removal efficiencies were obtained by introducing 1 wt% alginate. Alginate can desorb Cu²⁺ and Zn²⁺ ions from soil by forming unstable gels, which could be dissociated through electrolysis. However, Pb²⁺ ions did not easily migrate out of the contaminated soil. The density functional theory (DFT) calculations show Pb²⁺ ions could form a more stable coordination sphere in metal complexes than Cu²⁺ and Zn²⁺ ions. The metal removal efficiency was decreased by increasing alginate dosage at a high level. More alginate could provide more carboxyl ligands for divalent metal ions to stabilize gels, which were difficult to dissociate by electrolysis. In summary, the results indicate it is potential for introducing alginate into an electrokinetic system to remediate Cu- and Zn- contaminated soil.