Environmental Sciences Europe最新文献

Decomposition of submerged plants releases organic matter, nitrogen, and phosphorus into water bodies, generating an important impact on the aquatic ecosystem. This study explored the influence of growth substrate with different compositions on the decomposition process of eelgrass (Vallisneria spinulosa Yan, V. spinulosa Yan). The sediment + iron–carbon fillers system exhibited significantly lower concentrations of total nitrogen (TN) and total phosphorus (TP) in the overlying water than other systems, with the maximum values of 5.68 and 7.05 mg/L, respectively. The addition of ceramic and calcium nitrate promoted the formation of HCl-extracted phosphorus (HCl–P) in the sediment, while the addition of iron–carbon fillers increased the content of NaOH-extracted phosphorus (NaOH–P). Three-dimensional fluorescence spectroscopy of dissolved organic matter (DOM) in overlying water showed that different substrate compositions did not significantly affect the compositions of organic matter released during the decomposition of V. spinulosa Yan. The microbial community and abundance in each experimental group changed significantly before and after the decomposition of V. spinulosa Yan. The sediment + iron–carbon fillers system showed significantly higher abundance of microbial community than other systems, with the enrichment of functional bacteria related to denitrification and sulfate reduction. In contrast, the sediment + calcium nitrate system exhibited a smaller change of microbial community abundance, with the enrichment of aerobic denitrifying bacteria. In this paper, it was found that the sediment + iron–carbon group had a good adsorption effect on nitrogen and phosphorus released during the decomposition process of V. spinulosa Yan, and had a good effect on water purification as the growth substrate of submerged plants.

The bioaccessibility of Zn, Ni, Cd, and Cu is a critical parameter for accurately assessing the human health risk associated with oral exposure to soils contaminated with heavy metals. However, most studies have evaluated the bioaccessibility of these metals without considering the impact of metallic chemical fractionations and human gut microbiota, which are important factors affecting the uptake of heavy metals. In this study, the bioaccessibility of Zn, Ni, Cd, and Cu in soils was measured in an improved in vitro model. The metallic chemical fractionations and bioaccessibility of heavy metals in the sterilized colon phase were also investigated. The results showed that the bioaccessibility of all four heavy metals was below 70%, indicating that relying solely on total metal concentration for assessing human health risks would result in overestimation. The exchangeable, bound to carbonates, and bound to iron and manganese fractions (F123) of heavy metals were found to be close to their bioaccessibility. Furthermore, the bioaccessibility of heavy metals in the gastric phase was strongly and positively correlated with their F123 values (r of Zn, Ni, and Cu were 0.80, 0.57, and 0.68, respectively), highlighting the close connection between metallic chemical fractionation and bioaccessibility. The bioaccessibility of Ni and Cd was found to be higher in the sterile colon phase compared to the active colon phase, whereas Cu showed lower bioaccessibility in the sterile colon phase. The significant differences in heavy metal bioaccessibility between the active and sterile colon suggested that human gut microbiota in vitro played a key role in the adsorption and desorption processes of heavy metals in the intestine. These findings underscore the importance of taking into account both metallic chemical fractionation and human gut microbiota in vitro when assessing the bioaccessibility of heavy metals and their associated health risks.

The ECHA guidance on persistence (P) assessment has been updated with respect to non-extractable residues (NER). Unless further characterized, total NER shall be considered as non-degraded parent compound. We investigated how different NER fractions affect degradation half-lives (DegT50) of chemicals and the P assessment. Total NER consist of the fractions sorbed/sequestered (NER I), covalently bound (NER II), and bioNER (incorporated into the biomass, NER III). NER I pose a risk due to potential release, NER II have much lower release potential, and bioNER do not have any. NER I and NER II are considered as xenoNER. Data from 46 degradation tests with 24 substances were analyzed to find DegT50 for four scenarios: (i) extractable parent compound, (ii) parent plus total NER, (iii) parent plus xenoNER, and (iv) parent plus NER I. The microbial turnover to biomass (MTB) model was applied to calculate bioNER, and then xenoNER were calculated as total NER minus bioNER. The half-lives were determined by the fit program CAKE, using single first-order kinetics (SFO) for all fits. We found increasing degradation half-lives for the scenarios: extractable parent only < parent + NER I < parent + xenoNER < parent + total NER. A third of all chemicals show half-lives above the persistence criterion (120 days in OECD 307 and 308, and 40 days in OECD 309) for scenario i, and two thirds with scenario ii and, therefore, would be classified as ‘persistent’. For two compounds, the subtraction of bioNER led to a change to ‘not persistent’. The inclusion of NER in the P assessment (ECHA 2017, 2023) will thus have significant effects on the DegT50 of compounds and the persistence assessment. Experimental quantification of NER I (scenario iv) significantly reduces half-lives, in comparison to total NER (scenario ii). The results are closer to half-lives for parent only (scenario i) and give the lowest acceptable DegT50 below the vP criteria under the latest guidance. In addition, refining the DegT50 based on modelled bioNER can provide a more realistic option for persistence assessment, without laborious and costly analyses for NER I determination, when considered in the regulatory assessment of persistence. Moreover, bioNER can also be calculated for existing test data.

Sewage treatment plants are considered as important pathways for the transfer of perfluoroalkyl and polyfluoroalkyl substances (PFAS) to the environment. In conventional wastewater treatment, some of these compounds accumulate in sewage sludge via sorption onto suspended solids posing a potential environmental threat during sludge disposal and reuse. This review paper summarizes data for the occurrence of 182 PFAS from different classes in sludge matrices. Most of these monitoring data originate from Europe, Asia and North America, while limited data are available from Africa and South America. The most commonly studied classes of PFAS are perfluoroalkyl carboxylic acids, perfluoroalkyl sulfonic acids, and perfluoroalkyl sulfonamides, while few results are available for the occurrence of new generation PFAS such as GenX. The range of the observed concentrations varies between 0.01 ng/g d.w. for perfluorobutane sulfonic acid to some μg/g, depending on the compound, with the highest concentrations found for perfluorooctane sulfonic acid (8.2 μg/g d.w.). Limited information exists for the fate and removal of these substances in full-scale anaerobic digesters while recent articles indicate that some PFAS can be biotransformed under strictly anaerobic conditions. The exact mechanism remains unclear; additional data are needed to identify transformation products, apply mass balances, and understand the role of specific microorganisms. As regards novel thermal processes, encouraging results were recently published for the destruction of specific PFAS in hydrothermal liquefaction and carbonization, ranging between 55 and 100%, depending on the compound and the experimental conditions applied. Future studies should expand the list of studied compounds and focus on the mechanisms of their removal. PFAS are transferred to agricultural lands during sewage sludge reuse and their concentrations in soil are related to the applied biosolids’ loading rates. The parameters that affect leaching and desorption of PFAS from sludge, their plant uptake and possible threats for the environment and human health from the use of sewage sludge as soil amendment should be examined in long-term studies. ZeroPM project aims to address some of the literature gaps regarding the behavior of PFAS during sludge treatment focusing to the modification of anaerobic digestion and to the use of hydrothermal carbonization.

A risk-based strategy is presented aimed at prioritizing chemicals screened as potential persistent, mobile and toxic (PMT) or very persistent and very mobile (vPvM) substances. Prioritization is done to strengthen the decision-making process regarding actions that might be taken against chemicals screened as potential PMT/vPvM substances. Such actions can range from acquiring additional data aimed at reducing uncertainties in toxicological effect concentrations or internal exposure concentrations to—in case of acceptable uncertainty—suggesting compounds for prevention and/or removal measures in order to limit future exposure. The prioritization strategy is developed within the ZeroPM project and applies a variety of tools, including in silico and in vitro models for exposure and toxicity hazard assessment. These tools will be applied to chemicals identified as PMT/vPvM substances, with a preliminary emphasis on substances belonging to three chemical classes, i.e. perfluorinated compounds, triazines and triazoles. Here we describe the ZeroPM approach providing a proof-of-principle illustrative example, based on data-rich substances, results from which demonstrate how prioritization can be achieved using a risk-based approach that uses data obtained from new approach methodologies (NAMs) and environmental exposure concentrations, obtained either through modelling or monitoring studies. Results are communicated using a risk-based prioritization matrix, which can be used to help to communicate prioritization needs, such as identifying data gaps or for guiding actions aimed at mitigating exposure. The precision and accuracy of the prioritization matrix is evaluated using several data-rich chemicals, which identifies perfluorooctanoic acid and perfluorooctane sulfonic acid as high priority, due to a combination of toxicity and exposure estimates, whereas atrazine and melamine are observed at lower priority. The proposed risk-based prioritization framework thus represents a complementary source of information that should help support regulatory decision-making for PMT/vPvM substances.

Biopesticides have received increasing global attention as environmentally friendly alternatives, allowing for more sustainable pest and disease control. In order to be registered or authorized for use, safety studies need to be submitted for regulatory risk assessments. However, it has been frequently reported that, in particular, microbial pesticides have a number of challenges when it comes to non-target organism testing. For instance, study results from such tests are often difficult to interpret or they lack consistency and accuracy. Reasons for this can be found firstly in the heterogeneity and resulting complexity of microbe-based pesticides comprising different taxonomic groups (e.g., bacteria, fungi, and viruses), and secondly in the lack of appropriate guidance for testing these different microbial agents considering their unique biological properties. The present review gives an overview of the available test guidelines by reflecting the current regulatory background in the area of environmental risk assessment of microbial pesticides and describes general and specific issues associated with safety studies on terrestrial vertebrates, aquatic organisms, bees, non-target arthropods other than bees, meso- and macro-organisms in soil, and non-target terrestrial plants. Proposals for improvement of existing test guidelines or guidance documents are provided and further discussed.

A Central European catchment underlain by base-poor orthogneiss was studied using mass budgets and Mg–Ca–Sr isotope systematics. For 50 years, the catchment received large amounts of partly soluble dust from a nearby cluster of coal-burning power plants, while suffering from acid rain and severe spruce die-back. Our objective was to investigate to what extent anthropogenic dust contributes to Mg and Ca in runoff and to identify fractionations affecting Mg and Ca isotope composition of 13 ecosystem pools and fluxes. We hypothesized that if Mg and Ca runoff fluxes were significantly larger than their atmospheric inputs, Mg and Ca isotope ratios in runoff would converge to those of bedrock Mg and Ca. This relationship could be obscured by isotope fractionations. Strontium characterized by negligible isotope fractionations served as a Ca proxy. There was a strong positive correlation between Mg and Ca fluxes via spruce throughfall and catchment runoff. Monitoring of rainfall, canopy throughfall and runoff fluxes revealed a 20-, 15- and 15-fold excess of Mg, Ca and Sr in runoff, respectively, compared to atmospheric deposition fluxes. This sizeable excess per se would indicate predominance of geogenic base cations in runoff. The behavior of Mg and Ca isotopes was de-coupled. Petrographic study indicated that 92% of bedrock Mg was bound to easily dissolving biotite, 97% Ca was present in plagioclase, and nearly all Sr was in orthoclase. While Mg isotope ratios in bedrock and runoff were indistinguishable, corroborating predominantly geogenic Mg in runoff, Ca and Sr isotope ratios in bedrock and runoff were significantly different, consistent with a non-negligible contribution of atmospheric Ca and Sr to runoff. Previous study of sites underlain by felsic rocks indicated that the δ⁴⁴Ca value of apatite was often higher than the δ⁴⁴Ca value of plagioclase. Should weathering of apatite and/or plagioclase preferentially release Ca that is isotopically heavier than bulk rock, the geogenic Ca source at JEZ would converge to the mean δ⁴⁴Ca value of runoff. Calcium isotope data would then become more consistent with a major role of geogenic Ca in JEZ runoff indicated by mass balance data.

Microplastics (MPs) are a global problem due to their pervasiveness and possible harm to humans and other living organisms. It has been reported that a wide variety of foods, including seafood, contain microplastics. Dried pink shrimp (Penaeus notialis) popularly called ‘dried crayfish’ is a common delicacy in many Nigerian and West African local recipes. To our knowledge, this is the first study to assess the presence of meso- and microplastics in dried shrimp in Nigeria. From a survey of five popular markets in Ekiti State, South West, Nigeria—Shasha, Oja Oba, Agric Olope, Afao (Ikere), and Oja Isale (Ifaki), 15 samples of sun- and smoke-dried pink shrimp were purchased, and their meso- (5–25 mm) and microplastic (1 to < 5 mm) content was examined. Visual inspection showed that mesoplastic particles were present in all the dried shrimp types examined. A 10% KOH solution was used to digest the samples after they had been weighed. The samples were exposed to density floatation in KI solution, followed by filtration, drying, examination under a stereomicroscope, and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectrophotometer. The mean concentration of mesoplastics per 10 g of sample was 2.13 ± 0.56 for sun-dried samples and 3.20 ± 0.90 for smoke-dried samples. Microplastics had a mean concentration of 6.47 ± 1.12 in sun-dried samples and 2.87 ± 0.90 particles/10 g in smoke-dried samples. Generally, the sun-dried shrimp showed a higher prevalence of microplastics than the smoke-dried samples. The ATR-FTIR results revealed the dominance of polyethylene, PE (80%) films and fibres, followed by styrene-butadiene rubber, SBR (12%), natural latex rubber, NLR (5%), and polyvinyl alcohol, PVA (2%). Polymer hazard index (PHI) denoted that PE microplastics had a PHI score of 877.8 classifying them in the hazard category IV which is a “danger” risk. The polymers may directly enter the human body when consumed via dried shrimp and cause health implications.

Graphical Abstract

Predicting evaporation is an essential topic in water resources management. It is critical to plan irrigation schedules, optimize hydropower production, and accurately calculate the overall water balance. Thus, researchers have developed many prediction models for predicting evaporation. Despite the development of these models, there are still unresolved challenges. These challenges include selecting the most important input parameters, handling nonstationary data, extracting critical information from data, and quantifying the uncertainty of predicted values. Thus, the main aim of this study is to address these challenges by developing a new prediction model. The new prediction model, named Gated Recurrent Unit–Multi-Kernel Extreme Learning Machine (MKELM)–Gaussian Process Regression (GPR), was used to predict one-month ahead evaporation in the Kashafrood basin, Iran. This model was executed in multiple stages. First, a feature selection algorithm was used to determine the most critical input parameters. A data processing technique was then employed to decompose nonstationary data into stationary intrinsic mode functions (IMFs). The GRU model then processed these components to extract their essential information. In the following step, the extracted information was inserted into the MKELM model to predict evaporation. Finally, the GPR model quantified the uncertainty of predicted values. Our research also introduces a new optimizer called the Salp Swarm Optimization Algorithm–Sine Cosine Optimization Algorithm. This algorithm was used to tune the model parameters. This algorithm's performance and the prediction models’ accuracy were evaluated using several error indices. According to the study results, the GRU–MKELM–GPR model performed better than other models in predicting monthly evaporation. It improved the training and testing mean absolute error values of the other models by 21%-43% and 8.2–33%, respectively. Moreover, the new model improved the R² (R-squared or coefficient of determination) values of other models by 5–12%. Generally, the main findings of this paper included the superior performance of the new model in predicting evaporation data and the superior performance of a new optimizer in adjusting model parameters. These findings highlighted the effectiveness of the suggested model in addressing the challenges associated with evaporation prediction.

The “Just Transition” concept aims to ensure an equitable shift toward low-carbon economies by minimizing negative impacts on workers, communities, and vulnerable sectors, while inclusively distributing the benefits of environmental policies. However, this process faces structural and conceptual barriers that extend beyond technical challenges, such as the lack of effective participation, power dynamics, persistent inequalities, and tensions between economic growth and sustainability. This work transcends traditional notions by adopting a plural and critical perspective from the Pluriverse to explore the challenges and opportunities in reshaping the Just Transition. We argue that integrating local knowledge and adopting epistemic justice approaches are essential for designing transitions that not only mitigate the climate crisis but also promote autonomy, social equity, and ecological regeneration.