Environmental Sciences Europe最新文献

Background

Iodinated contrast media (ICM) are pharmaceuticals widely used in X-ray diagnostics to improve image contrast. Due to their high dosage and minimal metabolism, ICM are excreted almost unchanged and can enter aquatic environments, appearing in surface water used for drinking water production. Although ICM are chemically stable, under certain conditions, they can release iodine and be transformed in iodinated by-products (I-DBPs) during the disinfection processes occurred in water treatment plants. Previous studies on this phenomenon have relied on experimental conditions that poorly reflect real-world drinking water treatment practices, in terms of ICM and disinfectants concentrations and contact times. Rather than challenging established literature, this study aimed to investigate whether chlorination can lead to the formation of iodinated trihalomethanes (I-THMs) from ICM dissolved in water samples, when disinfection is performed under real-world conditions. The evaluation focused on Germany, where high attention is posed on the environmental impact of ICM and their potential role in the formation of I-DBPs. Therefore, the experimental setup was designed to be aligned with the German Drinking Water Directive (TrinkwV 2023), reflecting realistic conditions for disinfectant dosage (chlorine < 1.2 mg/L) and contact time. Four ICM (iohexol, iomeprol, iopamidol, iopromide) were tested in two different raw waters, commonly used in Germany for drinking water production. Concentrations of ICM 10 µg/L (typical environmental level) and 100 µg/L (worst-case scenario) were applied, with additional tests for iopamidol at a maximum concentration of 3900 µg/L. The study also examined the role of free iodide in I-THMs formation.

Results

Results indicated no correlation between I-DBPs formation and the presence of ICM, even at the highest tested concentrations. I-DBPs were detected only in one raw water type, specifically the water samples with the highest dissolved organic carbon (DOC), suggesting that the composition of water, rather than ICM, modulate the formation of I-DBPs. Conversely, free iodide was confirmed as a significant contributor to I-DBPs generation when chlorinated.

Conclusions

Under standard German drinking water treatment conditions, ICM do not promote I-DBP formation. Instead, water matrix characteristics and iodides play a decisive role in I-DBPs formation.

Agricultural soils in China’s rice-producing regions face significant contamination from both cadmium (Cd) and arsenic (As), posing serious ecological and health risks. This study aimed to address the challenge of immobilizing both contaminants simultaneously using iron-modified biochars derived from rice straw (SIBC), pig manure (MIBC), and pine wood (PIBC). Characterization showed successful iron impregnation, with Fe content in SIBC, MIBC, and PIBC reaching 35.19%, 35.26%, and 35.79%, respectively. The modification also increased the specific surface area and porosity of the biochars, with PIBC showing a 10.46-fold increase. Incubation experiments demonstrated that iron-modified biochars were effective in reducing bioavailable Cd and As. PIBC reduced available Cd by 70.1%, while SIBC reduced available As by 29.2%. Sequential extraction analyses revealed that iron-modified biochars promoted the transformation of Cd into more stable, residual forms, and As into less available oxidizable and residual phases. Additionally, pore water chemistry showed a shift towards low-toxicity As(V), with SIBC and PIBC increasing As(V) content by 84.8% and 91.1%, respectively. Microbial analyses indicated that biochar amendments improved soil ecological health, increasing microbial α-diversity and the abundance of beneficial bacterial phyla like Proteobacteria, Acidobacteriota, and Gemmatimonadota. Among the biochars, SIBC was the most cost-effective and efficient amendment for the remediation of co-contaminated paddy soils, showing significant potential for reducing both Cd and As contamination.

The growing scarcity of clean water has led to the increased reuse of treated and even untreated wastewater, particularly in agriculture. However, this practice poses significant environmental and public health risks due to the presence of emerging contaminants such as antibiotics and antibiotic resistance genes (ARGs). This study presents an optimized electrochemical treatment system for the removal of ciprofloxacin (CIP) and antibiotic-resistant bacteria (ARB) from hospital wastewater, using a biochar/graphite anode and a graphene oxide coated hydrogel nano-TiO₂ cathode. Response Surface Methodology (RSM) based on a "Box–Behnken" design was applied to optimize operational parameters including pH, initial CIP concentration, current density, and contact time. Under optimal conditions, 94.3% removal of CIP was achieved. The system also demonstrated high disinfection efficiency for total coliforms, fecal coliforms, and E. coli, achieving near-complete microbial inactivation. These findings highlight the potential of electrochemical treatment systems as scalable, low-cost solutions for reducing pharmaceutical pollution and combating antimicrobial resistance in wastewater.

Cadmium (Cd) contamination has become one of the most critical soil pollution issues worldwide, with China experiencing particularly severe impacts. Yet, the potential of widely planted trees such as Populus for Cd phytoremediation remains insufficiently understood. Here, an 18-month greenhouse pot experiment was conducted using seedlings of Populus × euramericana exposed to five soil Cd levels (0–100 mg Cd kg⁻¹). Plants were separated into organs (leaf, branch, stem, root), and stems were further partitioned both longitudinally and radially to assess the spatial distribution and translocation of Cd. Cadmium concentrations in plants increased with soil Cd but followed a distinct organ hierarchy, with leaves containing the highest levels, followed by stems, roots, and branches. Within stems, Cd concentrations declined from the base to the top and from bark to heartwood. The bioaccumulation factor (BAF) increased with moderate Cd exposure (up to ~ 10 mg Cd kg⁻¹ soil) but sharply decreased at higher concentrations, revealing a physiological threshold beyond which Cd uptake was strongly inhibited. The translocation factor (TF), defined as the ratio of cadmium concentrations in shoots to roots, showed a similar non-linear response, peaking under moderate Cd levels and stabilizing thereafter, suggesting partial suppression of long-distance Cd transport under severe stress. These findings reveal a clear trade-off between Cd uptake efficiency and ecological stability in Populus, a deciduous tree species, which acts as an efficient Cd removing agent but stores most of the metal in foliage, posing both remediation potential and risk. The findings provide mechanistic insight into Cd uptake and partitioning in trees and inform the potential use of Populus in sustainable soil-remediation programs across Cd-polluted regions.

Microplastics and air pollution are both critical public health issues. This longitudinal panel study aimed to investigate the correlations and interactions among indoor polyethylene terephthalate (PET) and polyamide (PA, primarily PA6 and PA6,6) microplastics, outdoor air pollution, and inflammatory factors in exhaled breath condensate (EBC). Indoor microplastic levels were measured using high-performance liquid chromatography (HPLC) after depolymerization of PET and PA into terephthalic acid (TPA), 6-aminohexanoic acid (AHA), and 1,6-hexamethylenediamine (HMDA), respectively. Results indicated that PET, PA6, and PA6,6 microplastics were detectable in most indoor air deposition samples, with average levels of 13.11 (± 7.25) μg/m²/d, 5.06 (± 5.13) μg/m²/d, and 2.93 (± 4.36) μg/m²/d, respectively. Linear mixed-effects models revealed positive correlations between exposure to PET and PA microplastics and inflammatory markers in EBC, with these associations varying by gender. Furthermore, interactive effects were observed between indoor PET, PA microplastics and outdoor air pollutants on the level of interleukin-6 (IL-6) in EBC. These findings underscore the importance of controlling both microplastic and air pollution.

The discharge of synthetic dyes, especially from textile industries, poses significant environmental and health risks due to their toxicity, persistence, and resistance to degradation. To address this issue, a sustainable and cost-effective adsorbent, Pomelo Peel–Bentonite–Ferrous nanocomposite (PPB-Fe), was developed using a green chemistry approach that leverages agro-waste (pomelo peel), naturally abundant bentonite clay, and iron salts. Its goal is to aid in removing inorganic compounds from water solutions, making wastewater cleaner for reuse. The composite was extensively characterised using Fourier Transform Infra-Red (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy-Energy Dispersive X-ray analysis (SEM–EDX), Thermal Gravimetric Analysis-Differential thermal analysis (TGA-DTA), Brunauer–Emmett–Teller (BET), and Dynamic light scattering (DLS) methods, confirming its porous structure, crystalline nature, thermal stability, and large surface area. Adsorption isotherm studies using the Langmuir and the Freundlich models revealed that PPB-Fe is highly effective in removing Congo Red under favourable conditions. The Freundlich adsorption isothermal study provides better insight into the adsorption behaviour of PPB-Fe composite. The adsorption capacity (K_F) of the adsorbent was calculated to be 3.67, and the adsorption intensity (n) was 1 by the Freundlich model, indicating multilayer adsorption on a heterogeneous surface. The data suggested that the Freundlich isotherm model best describes the adsorption behaviour of the composite material in the present study. The reaction kinetics show the pseudo-second-order model. The rate constant of the pseudo-second order reaction was 5.28, and the q value was 427.50 mg/g. The adsorption increases with increasing temperature, indicating that the process is endothermic and spontaneous. The current research clearly demonstrates how fruit peel waste can be transformed into functional nanocomposites, specifically highlighting the PPB-Fe material as a promising, eco-friendly adsorbent for wastewater treatment with minimal chemical discharge. Notably, this study presents the first-time integration of pomelo peel waste, bentonite clay, and iron salts into a nanocomposite designed to efficiently remove textile dyes from water.

The offshore wind energy sector is experiencing rapid and large-scale expansion in Europe, driven by increasingly ambitious renewable energy targets that position it as a central component of global climate mitigation efforts. The increasing number of offshore wind projects in the North Sea requires comprehensive regulations to monitor and minimize the impacts on the marine environment during construction, operation and decommissioning. This policy brief aims to summarize current regulations for chemical emissions in the North Sea area by reviewing available national documents and websites for guidance in Belgium, Denmark, France, Germany, the Netherlands, and Norway in combination with information received from respective authorities. Based on the collected information, the policy brief will give recommendations for potential harmonization to increase the protection of the environment and facilitate procedures. The comparative analysis of national and transnational regulations for chemical emissions from offshore wind farms in North Sea bordering countries revealed that these are incomplete and differ between countries in terms of their specifications and level of detail. For example, specific rules for the application of galvanic anodes including the ban of zinc-based anodes are only available in Germany while several but not all countries prohibit the use of antifouling or other toxic paints. Incompleteness and differences may also be related to a lack of information on substances and their environmental effects. To achieve harmonization and more efficient protection of the marine environment, more data and minimum requirements on a regional level will be necessary, while at the same time, innovation may not be hampered and design and techniques should be further optimized and adapted based on latest available information.

The pace of species extinction and the destruction of nature may be even more dramatic than the speed of the climate crisis itself. The EU Nature Restoration Law (NRL), adopted in the summer of 2024, is intended to partially remedy damage to nature in EU member states by 2050. This study analyses whether the NRL is sufficiently effective in stopping biodiversity loss and preserving biodiversity. Methodologically, this investigation was conducted using qualitative governance analysis and legal interpretation of the NRL. Although the NRL is a step forward for various reasons, it is still not sufficient, measured against the obligation to preserve biodiversity and stop its loss, as stated in Art. 1 of the UN Convention on Biological Biodiversity (CBD), which entered into force in 1993. The NRL gives the EU Member States a further time extension, mostly until 2050, which is too long to wait, considering the planetary boundaries that have already been exceeded. Furthermore, the NRL primarily presents (not very clear) targets. Whether appropriate measures will be taken remains to be seen. Therefore, it depends heavily on the goodwill of the EU Member States. However, in view of the ongoing loss of biodiversity and earlier experiences with EU environmental law, there are major doubts about this. In addition, the targets are weakened by several exemptions. The targets are inadequate for conservation, that is, the protection and restoration of biodiversity. The NRL also does not specify the percentage of the total area of an EU Member State that must be covered by the protected areas. Furthermore, the NRL shows serious governance problems, such as problems of depicting, enforcement problems, or lack of ambition. The NRL (and nature conservation law as a whole) fails to take the essential step towards preserving biodiversity: addressing the drivers of destruction, such as livestock farming and pesticides, by means of quantity governance. Against this backdrop, current attempts to further weaken the NRL appear to be highly problematic from an ecological perspective.

Cardiovascular-kidney-metabolic (CKM) syndrome is a critical determinant of mortality. Research has demonstrated that environmental factors are significant risks for CKM, and heavy metal exposure contributes to various diseases. However, the impact of heavy metal on CKM syndrome has not been evaluated. This investigation was to elucidate the link between heavy metal and advanced CKM stages from National Health and Nutrition Examination Survey (NHANES). Multivariate logistic regression, weighted quantile sum (WQS) model, restricted cubic spline (RCS), and subgroup analysis were employed to analyze the relationships. Mediation analysis explored whether inflammation mediated the effects. 4,400 participants were included in this study, with 872 diagnosed with advanced CKM stages. The results revealed a positive and linear association of heavy metal, including cadmium (Cd), cobalt (Co) and lead (Pb), with advanced CKM stages. Furthermore, heavy metal mixtures were also found to correlate with advanced CKM stages, showing that Cd, Co and Pb contributed the weights of 32.40%, 34.20% and 22.80%, respectively. Additionally, systemic immune-inflammation index (SII) was identified as a mediator in the association of Cd and Co with advanced CKM stages, accounting for 2.69% and 3.91%, respectively. Our findings suggest that heavy metal exposure, especially Cd, Co, and Pb, might contribute to the development of CKM syndrome. More studies are needed to investigate the relationship between heavy metal and CKM syndrome.

Background

Water quality assessment must rely on representative samples, but obtaining them is increasingly challenging given the growing number and diversity of trace contaminants emitted into water bodies. This study investigates whether and to what extent monthly grab sampling (GS), widely used in official monitoring programmes, provides reliable and accurate estimates of annual mean and maximum concentrations, and of annual riverine loads. Through a one-year systematic survey in two rivers using three sampling techniques in parallel, we evaluate low-frequency GS against time-proportional composite (TPC) and flow-proportional composite (FPC) sampling. The scope of 450 contaminants encompasses potentially toxic elements (PTE), pharmaceuticals, biocides, pesticides and PFAS, covering a broad diversity of emission patterns and environmental fate.

Results

For dissolved PTEs and pharmaceuticals, monthly GS delivered approximately correct annual average concentrations, but potential underestimation and overestimation were also observed. Contaminants with seasonal patterns or those emitted during short-term events, such as many pesticides and biocides, PFAS and total PTEs, were not adequately depicted by low-frequency GS, leading to varying degrees of underestimation and seldom also to overestimation. This applies to average annual concentrations but particularly to loads. Integrated composite sampling, especially flow-proportional, performs significantly better for such contaminants. Worthy of attention are cases of low and highly variable concentrations, such as ibuprofen, lindane and PFNA in this study. While integrated composite samples clearly demonstrated their non-negligible presence, monthly GS failed to detect them.

Conclusion

The widely applied monitoring approach relying on monthly GS is only sufficiently reliable for contaminants being emitted fairly constantly and transported primarily in the dissolved phase. Even then, its good performance is mostly limited to assessing average concentrations and thus chronic exposure, while integrated composite sampling can significantly improve the accuracy of load calculations. For contaminants with variable and dynamic concentration patterns, FPC sampling performs considerably better, especially in terms of load calculations, followed by TPC sampling. However, the latter is simpler to implement. GS-based underestimations pose a significant risk of incorrectly assessing compliance with environmental quality standards if the concentration level in rivers is not very far below or above the thresholds, as was often the case in our study area.