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Decades of research demonstrated that microbes can remediate petroleum-contaminated environments through biodegradation of hydrocarbons. Recent studies have applied signature metabolite analysis to investigate hydrocarbon-contaminated sites, focusing primarily on aquifer systems and metabolites of relatively water-soluble monoaromatic hydrocarbons. However, the number of studies involving non-targeted analysis and identification of individual metabolites in environmental samples is limited. In addition, metabolite patterns in crude oil-contaminated samples are rarely compared to those in the unaltered crude oils. In this study, we identified metabolites in complex environmental samples and crude oils from a former oil sands mining site using non-targeted gas chromatography-mass spectrometry. Based on these results, we suggest potential biodegradation processes that may account for the formation of the observed metabolites. The non-target results from water samples contaminated with crude oil showed that aromatic acids were the dominant metabolites. We observed that arylacetic acids were particularly abundant in the water samples when the metabolite patterns were compared with those found in crude oil and oil sands samples formerly produced at the site, as well as those found in oil-contaminated soil samples. The dominance of arylacetic acids is evidence that the microbial communities have a limited capacity for α-oxidation, i.e. an enzymatic attack on the methylene group, which is necessary to further degrade these compounds. Therefore, aromatic acids may be enriched at sites with long-term exposure to crude oil. Our study demonstrates that non-targeted metabolite analysis can provide an insight into the prevalent pattern of carboxylic acid metabolites and degradation processes in hydrocarbon-contaminated habitats., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 The Authors. Published by Elsevier B.V. All rights reserved.)

Selenium (Se) is an indispensable trace element to human health, yet its biological tolerance threshold is relatively narrow. The potential application of machine learning methods to indirectly predict the Se content in crops across regional areas, thereby validating the reasonableness of soil health thresholds, remains to be explored. This study analyzed the factors influencing Se absorption in crops from longevity regions and employed machine learning models to predict the bioconcentration factor of Se, thereby obtaining selenium content in these crops and ultimately estimated the Se threshold for healthy soils. The results indicated that the Artificial Neural Network (ANN) model demonstrated the best predictive performance for the bioaccumulation factor (BAF) of Se in crops. The maximum permissible concentration of Se in rice was 0.17 mg/kg, while the minimum was 0.03 mg/kg; for maize, the maximum permissible concentration was 0.25 mg/kg, and the minimum was 0.04 mg/kg. Approximately 68 % of the arable land in the study area was suitable for cultivating Se-rich crops, providing important insights for the optimization of crop cultivation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

The use of lithium (Li) in decarbonization strategies has positioned it as a central component of modern technological advances, particularly in battery applications. However, the increasing demand for Li has raised concerns about its environmental consequences, which are poorly documented. This study aimed to fill this knowledge gap by examining the impact of Li on soil bacterial/fungal communities. Using a microcosm approach, we explored the impacts of increasing Li concentrations on both microbial community structure and activities. Our results revealed significant changes in bacterial/fungal communities, particularly in the bacterial communities. Most of the indicator species were negatively correlated with the Li gradient, reinforcing the harmful effect of Li. Proteobacteria dominated at low concentrations, whereas Firmicutes were the most abundant at high concentrations. OTUs affiliated with the genus Alicyclobacillus represented >29 % of the total affiliated OTUs at the highest Li concentrations. Moreover, Alicyclobacillus fastidiosus showed resilience and specific adaptation to Li. Fungal communities showed less pronounced changes, with Mucoromycota remaining the dominant phylum at all concentrations. Nevertheless, some genera presented correlations with Li concentration, particularly the plant mutualists Leptodontidium, Oidiodendron, and Solicoccozyma. In addition, rapid decreases in several enzymatic activities crucial for the functioning of the carbon, nitrogen and phosphorus cycles were noted. Accordingly, microbial respiration was also impacted by high Li concentrations. Finally, a correlative analysis linked the decreases in enzyme activity to decreases in the abundances of both Proteobacteria and Ascomycota. These results underline the multiple impacts of Li on bacterial/fungal communities, highlighting both structural alterations and changes in microbial activities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

Polychlorinated naphthalenes (PCNs) and polychlorinated biphenyls (PCBs) are toxic contaminants that were produced and used in large quantities for their stability, inertness, and other desirable electrical, cooling, and lubricating properties. Due to their environmental persistence and improper disposal, these contaminants have become broadly distributed in the environment. This study examines the levels, composition, distribution, and potential sources of these compounds in surface soils and street dusts collected at 19 residential and industrial areas in Detroit, Michigan. Each sample was analyzed for 32 PCN and 37 PCB congeners using gas chromatography/mass spectrometry. The geometric mean concentrations of total PCNs and total PCBs were 61 (range:11-1933) and 432 (range: 32-18,637) ng/g, respectively. The most common PCNs were tetra- to hexacongeners and PCN-59 was most prevalent individual congener. For PCBs, hexaPCBs were most common and PCB-158 was dominant. PCN and PCB levels in soils at most sites exceeded health-based guideline levels. Given the short half-lives of PCNs and restrictions on PCN and PCB production, our results imply ongoing or recent releases. Emission sources identified by principal components and other analyses include industrial thermal processes included fuel combustion and electrical waste handling at a scrap metal processor for PCNs and PCBs, respectively. The presence of sources and "hotspots" of these toxic "legacy" contaminants in urban settings like Detroit highlight the potential for human exposure and the need to identify and control sources to prevent further environmental dispersal, exposure and risk., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

The presence of heavy metal(loid)s in sewage sludge is a cause of concern and an obstacle to its agricultural valorisation. This study analysed the elemental composition of sewage sludge from 42 Portuguese wastewater treatment plants (WWTPs) during summer and winter, investigating heavy metal(loid) contamination, nutrient content, and potential risks related to sludge application to agricultural soils. Levels of 8 heavy metal(loid)s were investigated, ranging from not detected (Hg) to 5120 mg kg -1 dw (Zn), decreasing in the order Zn > Cu > Cr > Ni > Pb > As>Cd > Hg. The legal requirements for agricultural use of sludge were overall met, but elevated levels of Zn and Cu, linked to industrial sources, exceeded the permitted limits in 3 WWTPs. On average, N, P, K, Mg, and Ca comprised 80 % of the sludge nutrient profile. No seasonal variations were found, but sludge composition varied with WWTP size, wastewater origin, and between thickened and digested samples. Environmental hazard indicators showed significant sludge contamination with Zn, Cu, and Cd. However, the geoaccumulation index, potential ecological risk indicators, and risk characterization ratios showed no significant risks to sludge-amended soils, assuming a single application of 5 tons ha -1 . Human health risk assessment for workers handling sewage sludge identified dermal contact as the main route of exposure, with non-carcinogenic risk for Cr and carcinogenic risk for Ni and Cr at the highest reported levels. Sewage sludge produced in Portugal was considered suitable for agricultural use, provided that it is closely monitored and well-managed to meet the needs of crops and receiving soils, while mitigating environmental risks., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 The Authors. Published by Elsevier B.V. All rights reserved.)

Semi-volatile organic compounds (SVOCs) are widely distributed across the globe, including polar regions. This study investigates the distribution and bioconcentration of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) in soils and Colobanthus quitensis, while also estimating potential emission sources. Results indicated high concentrations of PAHs in soils and plants from the Sub-Antarctic region, while OCPs and PCBs were more prevalent in the Antarctic region, with higher contaminant concentrations found in soils than in plant tissues. Hexachlorobenzene (HCB) and dichlorodiphenyldichloroethylene (p,p'-DDE) were significantly higher in the Antarctic region, suggesting historical dichlorodiphenyltrichloroethane (DDT) use, while PCB 153 and 180 were the most representative PCBs in the Antarctic region. Phenanthrene (Phe) was the dominant PAH in both regions. The bioconcentration factor analysis from soils (BCF Soils ) revealed potential anthropogenic influences for certain contaminants, including γ-hexachlorocyclohexane (γ-HCH) and PCB 9 in the Sub-Antarctic region, and HCB, p,p'-DDE, PCB 9, and benzo-naphtho-thiophene in the Antarctic region. However, compounds with higher hydrophobicity showed lower Bioconcentration factor (BCF Soils ) values, indicating a tendency to accumulate in soil rather than plant tissues. This was consistent with the inverse relationship found between BCF Soils and the octanol-water partition coefficient (Log K OW ). Diagnostic ratios of PAHs revealed a predominantly pyrogenic source in the Sub-Antarctic region, while a mixture of sources was observed in the Antarctic region., Competing Interests: Declaration of competing interest Cristobal Galban-Malagon reports financial support and administrative support were provided by Universidad Mayor. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

Metolachlor is the most heavily used member of acetanilide herbicides, which are noted for forming highly soluble metabolites in root zone soils soon after field application. The two primary metabolites of metolachlor, metolachlor ethane sulfonic acid (MESA) and metolachlor oxanilic acid (MOXA), retain the same chiral chemistry as their source and are important tracers of nitrate loading from agricultural cropland. New analytical methods for separating the isomers of MESA and MOXA, enable studies assessing changes in the abundance of atropisomer pairs of the carbon chiral enantiomers in environmental samples. These changes were documented starting with the atropisomers in the parent metolachlor structure, leading to soil-degraded metabolites, and then in samples collected over 3 years from 15 subwatersheds in the Upper Choptank River Watershed. The influence of drainage differences, %hydric soil and slope, across the watershed strongly correlate with shifts in atropisomer abundance ratios, especially for those enantiomers of MOXA and MESA with axial aS rotations. The hypothesis is that differentiating atropisomer chiral shifts occur as the compounds exit to receiving waters. These findings offer a novel tool to study the transport of these important tracers of cropland-influenced groundwater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

Micro and nanoplastics (MNPs) pose significant environmental concerns due to their potential implications for ecosystems and human health. While previous research has primarily focused on the environmental impacts (aquatic ecosystem, soil health) of MNPs, this review investigates their interactions with agricultural stored products, specifically their effects on stored product pests and grain quality. MNPs can infiltrate grains through various pathways, including atmospheric deposition, plastic residues from cultivation, and pest activity. These contaminants may influence pest feeding and behavioral patterns, reproductive cycles, and development. Simultaneously, MNPs have the potential to alter grain properties, including mineral content, protein composition, and starch synthesis, potentially compromising nutritional quality. Understanding these interactions is critical for developing strategies to mitigate the dual threats of MNP pollution and pest infestations to stored agricultural products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

There is an urgent need to develop effective and sustainable methods to decrease sulfonamide (SA) contamination of soil. Herein, a non-homogeneous system of zero-valent metal-biochar-based composites was proposed and tested for persulfate (PS) activation. This system employed zero-valent iron (Fe 0 ) as an electron donor to catalyze the cleavage of the OO bond in PS, thereby generating reactive oxygen species (ROS) that degrade SAs. Notably, the incorporation of elemental sulfur (S) significantly mitigated the passivation of Fe 0 , leading to an enhanced degradation capability of the system. The system decomposes 84-97 % of SAs at their concentration in soil suspension 10 mg/kg in 3 h. Among the coexistence of several SAs, the system showed the fastest degradation rate of sulfisoxazole with a k obs of 0.0305 min -1 , nearing complete removal within 3 h. The system is resistant to the impact of organic matter in soil. It allows to decrease concentration of sulfadiazine in actual contaminated soil on 73 % in 2 h. The system remains effective with decreasing concentrations of PS from 20 mM to 2.5 mM, which lowered the operating cost. T.E.S.T software evaluation showed a significant reduction in the bioaccumulation toxicity and developmental toxicity of the degradation products, suggesting that the system is environmentally friendly. The high efficiency of the catalytic system, the simplicity and economy of the manufacturing process, the resistance to interference in real soil, and the environmental friendliness make this technology promising for mitigating the problem of the environment contamination by SAs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

Composting urban and rural wastes into organic fertilizers for land application is considered the best way to dispose of and recycle waste resources. However, there are some concerns about the long-term effects of applying various organic fertilizers on soils, food safety, and health risks derived from heavy metal(loid)s (HMs). A long-term field experiment was conducted to evaluate the effects of continuous application of chicken manure compost (CM), sewage sludge compost (SSC), and domestic waste compost (DWC) for wheat on the accumulation, transfer, and health risks of HMs. The results revealed that, compared with control or chemical fertilizer treatments, continuous application of CM raised the concentrations of cadmium (Cd), chromium (Cr), copper (Cu), and zinc (Zn) in topsoil by 29 %-38 %, 15 %-16 %,11 %-14 %, and 20 %-36 %, respectively; SSC increased the concentrations of Cd, Cr, Mercury (Hg), arsenic (As), Cu, and Zn by 18 %-26 %, 8 %-9 %, 310 %-329 %, 5 %-8 %, 17 %-21 %, and 19 %-35 %, respectively; and DWC elevated the concentrations of Cd, Cr, Hg, lead (Pb), and Zn by 20 %-28 %, 8 %-9 %, 118 %-118 %, 5 %-10 %, and 3 %-17 %. The HMs concentrations in wheat grain were almost unaffected by the application of the organic fertilizers except for Hg and Pb concentrations. However, the HMs concentrations in both soil and wheat grain remained far below the limits of regulation in China. The long-term application of organic fertilizers did not cause additional noncarcinogenic and carcinogenic risks associated with exposure to HMs. In conclusion, although the long-term application of various urban and rural organic fertilizers increased the concentrations of several HMs in the soil, it almost did not cause any additional adverse effects on wheat grain or increase the health risks., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025. Published by Elsevier B.V.)

More and more research is now being focused on the mercury contamination of remote mountain environments. This study aimed to explore the mountain soil of Tiger Hill, Darjeeling, through the lens of its mercury tolerant bacterial microbiome to characterize regional mercury pollution and isolate strains with mercury bioremediation potential. The soil bacteria isolated from the region displayed an extreme tolerance to mercury at previously unseen levels of up to 7 mg/mL. The mercury removal capacity of the two best isolates, MTD11C and MTD11E, identified as strains of Brevundimonas naejangsanensis and Staphylococcus arlettae, exhibited a mercury removal capacity of 99.74 % and 99.56 %, respectively. As per our research, such extreme tolerance to mercury as demonstrated by the bacterial strains has not been reported thus far. The prevalence of such tolerance in the microbiota of a region may well be an indication of the degree of mercury pollution harbored by it. Their tolerance to other heavy metals and antibiotics, as well as active plant growth promotion traits, were also characterized in this study. The topsoil of this region was estimated to contain elevated levels of mercury at around 0.52-2.39 mg kg -1 . Ecological risk assessment further showed the potential for harm to the environment posed by the level of mercury. Collected vegetation samples from tea plantations surrounding Tiger Hill displayed an accumulation of mercury in the leaves and roots of the tea plants as well, suggesting rampant mercury pollution that needs to be addressed., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2025 Elsevier B.V. All rights reserved.)

Microplastics (MPs) have become pervasive pollutants in terrestrial ecosystems, raising significant ecological risks and human health concerns. Despite growing attention, a comprehensive understanding of their quantification, sources, emissions, transport, degradation, and accumulation in soils remains incomplete. This review synthesizes the current knowledge on the anthropogenic activities contributing to soil MP contamination, both intentional and unintentional behaviors, spanning sectors including agriculture, domestic activities, transportation, construction, and industry. Furthermore, it examines the spatial distribution, accumulation, and abundance of MPs across various land use types, alongside a critical assessment of existing quantification methodologies. While the predominant metric for MP quantification is particle number concentration, integrating mass and area concentration enhances the ability to compare pollution levels, assess fluxes, and conduct risk analyses. Additionally, the review explores the transport behavior of MPs in soil, distinguishing between external mechanisms (abiotic factors: wind, leaching, and runoff, biotic factors: soil bioturbation and food chain interactions), and internal mechanisms that are impacted by the characteristics of MPs themselves (e.g., shape, color, size, density, surface properties), soil properties (e.g., porosity, pH, ionic strength, organic matter and mineral content), coexisting substances, and soil structural dynamics. The study of MP transport in soil remains in its early stages, with substantial gaps in knowledge. Future research should focus on integrating number, mass concentration, and area concentration for the more holistic quantification of MP abundance, and prioritize the development of more accurate and efficient methodologies. In addition, the investigation of MP transport and degradation processes under varying environmental conditions and soil management practices is critical for addressing this emerging environmental challenge., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

Permafrost predominates in polar and high mountain regions, encompassing nearly 15 % of the exposed land in the Northern Hemisphere. It denotes soil or rock that remains at or below 0 °C for the duration of at least two consecutive years. These frozen soils serve as a barrier to contaminants that are stored and accumulated in permafrost over extended periods of time. One of these chemical compounds is mercury (Hg), a heavy metal well recognized for its severe toxic effects. Mercury presents a major risk worldwide to ecosystems, biota and human health and is strengthened by the Minamata Convention on Mercury. The International Panel on Climate Change (IPCC) scientific group monitors and assesses the science related to climate change and highlights the significant impacts of global warming. The phenomenon known as Arctic amplification has accentuated warming of the Arctic in recent years and has led to the degradation and rapid thawing of permafrost. This process has significant implications in hydrology of the ecosystems and for the mobility of previously sequestered carbon and trace metals, such as Hg, with possible adverse environmental and human health impacts. In this article, we provide a comprehensive review of the current understanding of the Hg cycle in permafrost regions, exploring the effects of global warming on these intricate processes. Additionally, we highlight existing research gaps and propose directions for future investigations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The unique properties of per- and polyfluoroalkyl substances (PFAS) have driven their pervasive use in different industrial applications, leading to substantial environmental pollution and raising critical concerns about the long-term impacts on ecosystem and human health. To tackle the global challenge of PFAS contamination, there is an urgent need for sustainable and efficient remediation strategies. Phytoremediation has emerged as a promising eco-friendly approach with the potential to mitigate the spread of these persistent contaminants. However, addressing this complex issue requires interdisciplinary cutting-edge research to develop comprehensive and scalable solutions for effective PFAS management. This review highlights recent advancements in the detection, quantification, and monitoring of PFAS uptake by plants, providing a detailed description of PFAS accumulation in several plant species. Besides, the physiological and molecular responses elicited by these pollutants are described. Leveraging omic technologies, including genomics, transcriptomics, and proteomics, provides unprecedented insights into the plant-PFAS interaction. Novel approaches based on artificial intelligence to predict this interaction and up to date disposal and valorization methods for PFAS-contaminated plant biomass, are discussed here. This review offers an interdisciplinary approach to explore what has been discovered so far about PFAS phytoremediation, covering the entire process from contaminant uptake to sustainable disposal, providing a roadmap for future research., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study investigated the microbial diversity inhabiting the roots (rhizosphere) of macrophytes thriving along the Blesbokspruit wetland, South Africa's least conserved Ramsar site. The wetland suffers from decades of pollution from mining wastewater, agriculture, and sewage. The current study focused on three macrophytes: Phragmites australis (common reed), Typha capensis (bulrush), and Eichhornia crassipes (water hyacinth). The results revealed a greater abundance and diversity of microbes (Bacteria and Fungi) associated with the free-floating E. crassipes compared to P. australis and T. capensis. Furthermore, the correlation between microbial abundance and metals, showed a strong correlation between fungal communities and metals such as nickel (Ni) and arsenic (As), while bacterial communities correlated more with lead (Pb) and chromium (Cr). The functional analysis predicted by PICRUSt2 identified genes related to xenobiotic degradation, suggesting the potential of these microbes to break down pollutants. Moreover, specific bacterial groups - Proteobacteria, Verrucomicrobia, Cyanobacteria, and Bacteroidetes - were linked to this degradation pathway. These findings suggest a promising avenue for microbe-assisted phytoremediation, a technique that utilizes plants and their associated microbes to decontaminate polluted environments., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Hlalele David Heisi reports equipment, drugs, or supplies was provided by University of South Africa - Florida Campus. Tonderayi S. Matambo reports a relationship with University of South Africa - Florida Campus that includes: employment. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Organic fertilizers were produced through maggot-composting (MC) and natural composting (NC) using swine manure, and the migration, contamination, and health risks of heavy metals (Zn, Cu, Cd, Cr, Pb) were evaluated within a fertilizer - soil - ryegrass - Rex rabbit system. After 70 days of treatment, heavy metals were concentrated by 43.23 % to 100 % in MC and 52.82 % to 90.91 % in NC, higher concentration rate was observed in Cr and Cu in NC. The residual fractions of Zn, Cu, CD, Cr, Pb increased by 0.4 % to 30.2 % in MC, and 3.4 % to 29.7 % in NC. More stable forms of Zn, Cr, and Cu were observed in NC, whereas Pb showed greater stability in MC. Post-fertilization, statistically higher levels of the five elements were obtained in NC treatment. Even their concentrations decreased in the soil, however, high initial background levels caused Cr and Zn to exceed standard thresholds in both treatments. Despite this, the geo-accumulation index (I geo ) and pollution load index (PLI) below 1, did not indicate a pollution risk. Cr levels exceeded feed limits in both roots and leaves, although the low BCF value in roots suggested limited risk. In rabbits fed with 48 % ryegrass, significantly higher levels of Zn and Cu were detected in NC, with elevated Cr levels posed moderate to severe pollution risks in two treatments. Health risk assessments, including non-carcinogenic (HQ f ) and carcinogenic risks (CR f ), revealed Cr was the most cautionary element for both children and adults, even no significant carcinogenic risk exist. These findings provide key insights into mitigating heavy metal contamination from animal waste to rabbit meat., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cadmium (Cd) accumulation in rice poses significant risks to human health. The Cd accumulation levels vary widely among cultivars and are strongly associated with the rhizosphere microecosystem. However, the underlying mechanisms remain poorly understood. Here, we conducted a field experiment in Cd-contaminated areas with 24 popular regional cultivars. These cultivars were categorized into high Cd accumulation (HA) and low Cd accumulation (LA) groups based on their grain Cd content. Rhizosphere soil physicochemical properties were monitored, and key metabolites, microbiomes, and their interaction contributing to Cd accumulation were analyzed using omics-sequencing technologies and bioinformatics analysis. Metabolomic analysis identified distinct rhizosphere metabolite profiles between the HA and LA groups, with key metabolites showing strong correlations with Cd accumulation. Key metabolites in the LA group were linked to reduced Cd uptake and enhanced antioxidant defense mechanisms, while those in the HA group were associated with increased Cd mobility and uptake. Metagenomic analysis of the rhizosphere soil showed that the LA group harbored a more diverse and interconnected microbial community, with tax such as Syntrophaceae, Anaerolineae, Thermoflexales, and Syntrophales, along with metabolite such as disopyramide, playing central roles in Cd immobilization and detoxification. Additionally, the enhanced carbon, nitrogen, and phosphorus cycling in the LA group suggests a more robust nutrient assimilation process that supports plant growth and reduces Cd uptake. This study highlights the critical role of the rhizosphere microecosystem in regulating Cd accumulation and underscores the potential of selecting rice cultivars with favorable rhizosphere traits as a strategy for reducing Cd uptake., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

This study examined the impact of long-term manure organic fertilizer application (3, 8, 13, 18, and 22 years) on soil physicochemical properties, heavy metal (HM) accumulation, and microbial communities. Long-term manure application markedly elevated nutrient levels such as available N, P and K, and organic matter content in surface and soil profile. Total and DTPA-HM content in different vertical profiles increased with the application time. Fertilization increases the ratio of exchangeable fraction of Cd (2 %-17 %) and Zn (9 %-24 %). The risk assessment of HMs revealed that Cd posed the highest risk (moderate contamination level), followed by Cu, Zn, Pb, and Cr. Due to soil acidification, the time span exceeding the risk screening values of Cr, Cd, and Pb in agricultural land (GB 15618-2018) decreased 53.1, 41.2 and 411.8 years, respectiverly, and for risk intervention values of Cr, Cd, Cu, Pb and Zn, the time reduced to 318.5, 137.0, 71.1, 1029.5 and 19.1 years, respectiverly. Furthermore, manure application altered the composition and structure of the bacteria and fungi community. The abundance of Actinobacteria, Firmicutes, and Ascomycota increased, whereas Proteobacteria, Acidobacteria, and Basidiomycota was inhibited. SEM and RDA indicated that microbial communities were primarily influenced by pH, soil nutrients and HMs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study aimed to enhance humification and cadmium (Cd) remediation in compost by investigating the effects of three post-treatments: ultrapure water, citric acid, and ethylenediaminetetraacetic acid disodium (EDTA). The results revealed that the EDTA post-treatment significantly enhanced humification by facilitating an EDTA-Fenton-like system within compost comprising rice straw and river sediment to remediate Cd-contaminated sediment. EDTA post-treatment not only promoted humic substances and humic acid concentrations of up to 66.30 g/kg and 30.40 g/kg, respectively, but also led to a reduction in the Cd content and bioavailability factor by 75.02 % and 9.76 %, respectively. In addition, parallel factor analysis revealed two distinct components, while two-dimensional correlation spectroscopy showed that the polysaccharides and carboxyl groups in humic acid were preferentially bound to Cd. Overall, this study proposes a promising approach for enhancing humification and Cd remediation in compost by the EDTA post-treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Potentially toxic elements (PTEs) in soils threaten human health through several exposure pathways. However, health risks posed by PTEs in soils in developing countries have not yet been comprehensively investigated. Thus, such countries lack important information that is needed to implement sustainable solutions. In this study, we assessed the human health risks for 10 PTEs, including arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn), in Sudan focusing on soils affected by anthropogenic activities, such as industrial processes, gold mining, tannery, waste dumping, traffic (affecting roadsides), urban/rural agriculture, river, and coastal sediment land uses (LUs). For this purpose, we did a meta-analysis using 3430 PTE concentrations reported from 981 anthropogenically-affected soils in 76 publications between 1996 and 2024. Ingestion was the most common exposure pathway for both carcinogenic and non-carcinogenic PTEs. Hg and Mn were the main non-carcinogenic PTEs leading to adverse health effects in children in industrially-affected soils and coastal sediments, with average hazard quotient (HQ) and hazard index (HI) values >1. Cr and Ni caused the highest carcinogenic risk to children in all anthropogenically-affected soils as indicated by average incremental lifetime cancer risk values (ILCR >1 × 10 -4 ). Further major cancer risks for children were caused by As in urban agricultural and industrial LUs, Cd in >70 % of all LUs, and Pb at industrial and waste dump sites. Adults were under high cancer risks due to Cd in waste dump (ILCR = 9.09 × 10 -4 ) and Cr and Ni (ILCR >1 × 10 -4 ) in >75 % of all LUs. Cd contributed >50 % and >70 % to ILCR for children and adults along roadsides, respectively. Our findings can guide future research on the links between soil PTEs and human health risks in developing countries. We recommend establishing effective management strategies to reduce risks to human health based on the presence of PTEs in Sudanese soils., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Microplastics are a new type of pollutants that have attracted attention recently. However, there is limited research on the uptake of environmental microplastics by plants. In this study, scanning electron microscopy (SEM), micro-Raman spectroscopy, and Raman mapping were employed to identify and detect label-free micron-sized polystyrene (PS) microplastics accumulated in the roots and stems of maize (Zea mays L.) seedlings. The results demonstrated that the Raman spectra of PS microplastics were predominantly concentrated in the xylem and ducts of seedlings, confirming the transfer behavior of microplastics in the plants. The Raman spectra of PS microplastics in seedlings exhibited distinctive peaks at 621, 1002, 1030, and 1604 cm -1 , and the matching scores of these spectra with the standard PS Raman spectrum ranged from 40.61 % to 86.93 %. Additionally, the Raman mapping facilitated the precise identification and visualization of microplastics within the roots and stems of seedlings. The smallest size of the detected PS microplastics was ∼2 μm. This study provides new insights into the use of Raman spectroscopy for the detection of microplastics in plants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The introduction of microplastics (MPs) into soil ecosystems via compost application has emerged as a critical environmental concern. However, the ecological risks and degradation behavior of MPs in compost remain insufficiently understood. This review addresses these gaps by synthesizing recent findings on MPs in composting systems, focusing on their sources, impacts on compost quality, ecological risks, and degradation mechanisms. MP sources vary significantly across compost matrices-domestic waste, sludge, and agricultural waste‑leading to differences in their types and quantities. MPs adversely impact compost quality by disrupting its physical structure and impairing fertility, aeration, and water retention. Furthermore, their persistence after compost application can result in long-term environmental accumulation, posing risks to soil ecosystems and biological health. This review also explores the aging and degradation of MPs during composting, a complex process influenced by physical, chemical, and biological mechanisms. Finally, we propose future research directions, emphasizing the development of standardized methodologies to assess MP behavior in compost and strategies to mitigate associated risks. These insights contribute to advancing sustainable waste management and environmental protection practices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Microplastics (MPs) contamination is pervasive in agricultural soils, significantly influencing carbon and nitrogen biogeochemical cycles and altering greenhouse gas (GHG) fluxes. This review examines the sources, status, mechanisms, and ecological consequences of MPs pollution in agricultural soils, with a focus on how MPs modified soil physicochemical properties and microbial gene expression, ultimately impacting GHG emissions. MPs were found to reduce soil water retention, decreasing soil respiration and increasing emissions of CO 2 , CH₄, and N 2 O. They also enhanced soil aggregate stability and influenced soil organic carbon (SOC) sequestration, contributing further to GHG emissions. MPs-induced increases in soil pH were associated with suppressed CH₄ and N 2 O emissions, whereas the abundance of genes encoding enzymes for cellulose and lignin decomposition (e.g., abfA and mnp) stimulated enzyme activity, intensifying N 2 O release. Additionally, a reduced soil C/N ratio promoted denitrification processes. Changes in microbial communities, including increases in Actinomycetes and Proteobacteria, were observed, with a rise in genes associated with carbon cycling (abfA, manB, xylA) and nitrification-denitrification (nifH, amoA, nirS, nirK), further exacerbating CO 2 and N 2 O emissions. This review provides valuable insights into the complex roles of MPs in GHG dynamics in agricultural soils, offering perspectives for improving environmental management strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study evaluated the contribution of soil dust deposited on the surface of reed canary grass (Phalaris arundinacea) grown on historic lead (Pb) mine sites to the overall contamination of the biomass, with implications for phytoremediation, valorization and utilization. By applying a novel combination of imaging of plant material using X-ray computed tomography (XCT) and scanning electron microscopy (SEM), with washing experiments and bulk analysis, the research aimed to distinguish between (a) Pb uptake through biological processes (phyto-extraction), and (b) surficial dust and physical entrapment of Pb-rich dust on plants cultivated in contaminated soils (surface-contamination). The study established the presence and distribution of Pb-rich particles, which were difficult to remove even by means of sequential washing in 1 M hydrochloric acid and surfactant. Analysis confirmed that the majority of Pb contamination was due to dust, but with significant levels remaining even after intense washing. This questions the effectiveness of phytoremediation in reducing bioavailable soil Pb levels through phyto-extraction, compared to achieving mechanical stabilization or reducing dispersion during phyto-management, and may represent a challenge to the viability of subsequent processing and use of the biomass product. Site-specific variations in contamination levels were observed, underscoring the influence of both local environmental conditions and plant morphology on dust accumulation. These observations highlight the necessity for standardized washing protocols to be adopted and for better reporting of the actual washing methods used in phytoremediation research, so as to correctly assess levels of contaminant uptake and actual remediation. The conclusion is that residual surficial dust contamination of biomass may have been overlooked in many previous phytoremediation studies and as a consequence the reported phyto-extraction potential has been over-estimated., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Richard Lord reports financial support, equipment, drugs, or supplies, and travel were provided by Northumbrian Water Ltd. Richard Lord reports financial support, equipment, drugs, or supplies, and travel were provided by European Union. Benjamin Nunn reports financial support, equipment, drugs, or supplies, and travel were provided by Northumbrian Water Ltd. Benjamin Nunn reports financial support, equipment, drugs, or supplies, and travel were provided by European Union. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Antimony (Sb) contamination in soil has become a growing concern due to its toxic effects on ecological soil functions. Soil enzymes, which are effective biological indicators, play a crucial role in assessing the ecological impact of heavy metals in soil. However, the effects of Sb on soil enzyme activity, particularly during the ageing process, remain poorly understood. This study examines the ageing process of Sb in soil and its biological toxicity on three key soil enzyme activities (arylsulfatase, urease, phosphatase) at different enzyme pool levels (total, intracellular and extracellular). Our findings reveal that the ageing of exogenous Sb in soil follows a heterogeneous dispersion process, with the Sb ageing rate constant (|b|) in acidic soil (S1, red soil, pH 4.90) being 1.21 to 1.90 times higher than in alkaline soil (S2, gray desert soil, pH 8.12). This suggests that Sb stabilizes more rapidly in acidic conditions. Regarding Sb effects on soil enzymes, extracellular urease activity and the total enzyme activity index (TEI) of extracellular enzymes were particularly sensitive to Sb stress. Over the course of the ageing period, extracellular urease activity decreased by 23.46-57.85 % in both soils under Sb stress at 7000 mg·kg -1 . The inhibition of TEI by Sb ranged from 29.08 to 42.47 % in S1 soil, and from 12.47 to 20.65 % in S2 soil. Ecological dose (ED 10 ) values indicated that Sb concentrations of 24.86-184.00 mg·kg -1 caused a 10 % reduction in extracellular enzyme TEI, whereas higher Sb concentrations (29.63-1791.86 mg·kg -1 ) were needed to inhibit 10 % of extracellular urease activity. Overall, TEI of extracellular enzymes emerges as a more sensitive and reliable indicator of long-term Sb contamination. This study provides essential insights for monitoring Sb pollution and provides a basis for establishing a soil Sb pollution assessment and early-warning system., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

As the world's leading producer of pigs, China is now experiencing large-scale pollution derived from agricultural usage of untreated pig manure, where passivation of metal toxicity in pig manure is a major challenge. Here, the effect of green synthesized iron nanoparticle (G-nFe) addition on copper (Cu) transformations during thermophilic aerobic composting of pig manure was investigated. The results revealed that following addition of G-nFe passivation of active Cu forms, including exchangeable (EXC-Cu), carbonate-bound (CARCu), and iron and manganese oxide-bound (IMOCu) Cu increased by 66.8, 47.5, and 15.4 %, respectively. The fraction of Cu bound to organic matter (OM-Cu) also increased with composting and was influenced by G-nFe dose. Notably, addition of 500 mL kg -1  G-nFe increased OM-Cu to 52.9 %. Residual Cu (RESCu) concentrations initially rose within the first five days of composting, followed by a subsequent decline, demonstrating that G-nFe addition had dual effects: firstly, an initial 31.3 % increase in RES-Cu five days post-G-nFe addition; and secondly, a subsequent 60.9 % reduction over the entire composting process. Furthermore, OM, Humus and Fourier transform infrared (FTIR) analysis confirmed that the increase in OM-Cu, coupled with G-nFe, facilitated the transformation of Cu into OM-Cu fractions post-composting. This work thus provides new insights into how iron nanomaterials can increase passivation of metal ions during composting., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The application of pesticides increases crop yields but affects the structure and function of the soil microbial community. Halogens are common functional modification groups in chemical compounds, and innovative pesticides have been developed on the basis of these groups. However, the effects of different halogen substituents on soil microorganisms remain unclear. This study investigated the effects of three pyrethroid pesticides (deltamethrin, cypermethrin, and cyfluthrin) on the soil microbiota. Our results revealed that all these pesticides significantly reduced the stability of the bacterial communities and decreased bacterial diversity at high concentrations. Compared with deltamethrin (Br - ) and cypermethrin (Cl - ), low concentrations (0.5 mg/kg) of cyfluthrin (F - ) increased soil bacterial diversity by 23.14 % and increased the potential for nitrogen fixation by 2.00 % and nitrification by 3.39 %, thus making it a relatively eco-friendly option. Our findings provide new insights into the potential ecological effects of halogenated pyrethroid pesticides on soil ecosystems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Stabilized sludge products (SSP) are promising conditioners for saline-alkali soils, capable of enhancing soil physicochemical properties and stimulating microbial communities. However, there is limited knowledge regarding the effects of SSP on soil salt-discharge capacity and carbon/nitrogen cycles. Here, a six-month incubation experiment was conducted to evaluate SSP (0 % ~ 60 %) on saline-alkali soil properties, salt leaching, and microbial functions. It was found that after SSP (≥30 %) treatment, saline-alkali soils were significantly remediated (p < 0.01), with organic matter increasing by 5.3-9.8 times, nutrient levels rising to first-grade, porosity improving by 34.3 % ~ 93.3 %, and meso/macro-aggregates content increasing by 39.0 % ~ 201.3 %. The Na + leaching rate increased from 1.1 % to 53.3 % ~ 79.3 %, indicating a substantial improvement in salt-discharge capacity. Correlation analysis revealed that SSP organics loosened pore spaces by promoting soil particle agglomeration, which in turn improved salt-discharge capacity. Further, the 30 % SSP significantly increased the microbial functions involved in nutrient cycling, such as carbon fixation (photosynthetic pathway), nitrogen fixation, dissimilatory nitrate reduction, and nitrification (p < 0.01). Contribution analysis implied that the up-regulation of gene abundance assigned to carbon/nitrogen cycle was attributed to balancing effect of SSP on dominant genera. Finally, the excellent growth of alfalfa seedlings verified the soil productivity restoration of degraded saline-alkali soils. These findings provide new insights into salt stress alleviation and nutrient cycling in degraded saline-alkali soils., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Rice, as the most essential food grain, is frequently exposed to high concentrations of arsenic. Among the arsenic species, dimethylarsenate (DMAs(V)) is preferentially translocated from paddy soils to rice grains, posing serious threats to food safety and yield. Herein, we report an efficient strategy for DMAs(V) mitigation in paddy soils with nanoscale Zero-Valent Iron (nZVI). Species and concentrations of arsenic in paddy porewater were monitored during a 28-d soil-water incubation. Effects of nZVI dose towards microbial sulfate reduction and methane generation potential in paddy soils, which are crucial for arsenic methylation and demethylation, were analyzed via metagenomic sequencing. Results demonstrated that the maximal DMAs(V) concentration in paddy porewater decreased from 0.37 to 0.04 μM in arsenic-contaminated paddy soils with nZVI dose increasing from 0 to 5.0 g/kg. Accordingly, the maximal concentration of inorganic arsenite (iAs(III)), which is the precursor of DMAs(V), decreased from 1.39 to 0.23 μM. Furthermore, the application of nZVI reshaped the structure of microbial community in paddy soils. Specifically, the relative abundance of δ-proteobacteria involved in sulfate reduction, which is crucial for iAs(III) methylation, waned from 7.62 % to 3.17 %, while that of Methanomicrobia for DMAs(V) demethylation and methanogenesis proliferated from 7.03 % to 13.62 %, with nZVI dose increasing from 0 to 5.0 g/kg. Via simultaneous inhibition of DMAs(V) formation and acceleration of DMAs(V) transformation, nZVI efficiently controls the accumulation of DMAs(V) in paddy porewater. In conclusion, these findings prove the efficient performance for DMAs(V) mitigation with nZVI and uncover its underlying mechanisms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Ultramafic soils are a natural source of metals such as Ni, Co and Cr that can pose ecosystem and human risks. Here, we assessed the environmental, ecological, and human health (carcinogenic and non-carcinogenic) risks from exposure to ultramafic soils through an integrated approach using petrographic and soil mineralogical assessments together with total, available, bioaccessible, and soil fractions analyses of Ni, Co and Cr in ultramafic soils from Brazil. The metal concentrations were similar or up to 5-fold higher for Ni than other studies worldwide in ultramafic soils. Soil sequential extraction showed Co and Ni predominantly bound to Fe and Mn oxides, while Cr was mostly in residual fractions. Medium environmental risks were found for Ni (RAC = 13.0), but no environmental risks were associated with Co and Cr in soils. Ecological risks were high (PERI = 522.8) and significantly high (PERI = 1759.9). Low metal bioaccessibility led to acceptable carcinogenic and non-carcinogenic risks for all routes of human exposure to soil, but consuming vegetables grown in these soils posed unacceptable cancer risks (> 10 -3 ). Our results reinforce the need to monitor ultramafic areas regarding the mobility and availability of metals in the soil to ensure food safety and human health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Long-term fertilization contributes to the accumulation of cadmium (Cd) in soils and crops, yet the effects of different fertilization regimes on soil Cd dynamics and its uptake in rice remain poorly understood. This long-term field experiment aimed to elucidate how different fertilization regimes influence Cd bioavailability and mobility in soil, thereby affecting Cd accumulation in rice. Four fertilization treatments were tested, including chemical fertilizer (CF), rice straw incorporation (RF), and low (LM) and high (HM) rates of manure fertilizers. Results revealed that manure fertilizers treatments (LM and HM) significantly reduced Cd concentrations in brown rice compared to other fertilization regimes, with levels falling below 0.2 mg kg -1 . Compared to CF, the average Cd concentrations in brown rice under LM and HM were significantly reduced by 33.14 % and 15.88 %, respectively, and which was significantly reduced by 42.53 % and 27.70 % compared with RF. Additionally, the concentration of Cd in brown rice was significantly higher under HM than LM treatment. Partial least squares path model revealed that reductions in Avail-Cd and AciCd, coupled with the formation of low-crystalline iron plaque (IP-Feh and IP-Feh-Cd), were critical factors in decreasing Cd concentration in brown rice. Manure fertilizers reduced the availability of Cd in soil by increasing soil organic matter (SOM), pH, and the abundance of microbial phyla such as Latescibacterota and Gemmatimonadota. Manure application also increased cation exchange capacity (CEC) and Fe 2+ concentrations in soil, promoting IP formation on rice roots and effectively preventing Cd 2+ uptake. In conclusion, the application of manure fertilizers at low rates, particularly in combination with chemical fertilizer, is recommended to ensure the safe production of rice by mitigating Cd uptake., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The quantitative evaluation of antimony (Sb) accumulation in rice has garnered significant attention due to the potential risks to human health. A pot experiment was conducted to investigate the essential nodes of Sb transfer in soil-rice system. Seven step extract results showed that during the flooding period, organic matter releasing was the primary factor contributing 14.1 % to the increase in Sb availability, while weakly crystallized Fe-Mn oxides and sulfides respectively accounted for 6.9 % and 1.42 %. During the drainage period, a notable increase in active Sb was observed, coinciding with decrease in Fe-Mn oxides and sulfides bond Sb. The migration rate constant of Sb from the root to the above-ground parts increased dramatically during the early flooding stage, being 2000 times higher than that in the mid-to-late stage. The shoot-to-grain migration rate constant remained low, at 1.07 × 10 -2 d -1 and 3.52 × 10 -3 d -1 during the flooding and drainage periods, respectively. Consequently, Sb accumulation amount in the grain (11.5 μg) was 2.2 times and 6.24 times lower than that in the roots and shoots, respectively. This study quantitatively evaluates the key processes controlling Sb transformation, uptake and translocation throughout different growth stages of the rice plant., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The fate of arsenic in mineral soil stores over time is poorly understood. Here we examined arsenic loss over five decades from a managed grassland soil profile through analysing archived material from a long-term slurry (LTS) experiment at Hillsborough, Northern Ireland. A randomized block experiment was established in 1970 where a perennial ryegrass sward was seeded onto the site and subjected to control (no fertilization) and fertilization treatments using conventional (i.e. at farmers recommended application rate) mineral NPK fertilizer, and pig and cow slurry treatments. Soil (0-5, 5-10 and 10-15 cm), slurry applied, and sward off-take was archived each year. A mass-balance calculation found that control soils lost no arsenic down the 15 cm depth soil profile, the NPK treatment had a 10 % loss, while cow slurry caused 25 % loss, and a 35 % loss was observed for pig slurry. For treatments with arsenic loss, removal was linear over the 50 years of study in 2 out of the 3 blocks, with the 3rd block showing little or no change. Principal Component Analysis (PCA) found that arsenic was most positively associated with soil magnesium, manganese and nickel, while negatively associated with pH, organic carbon, phosphorus and silicon. Laser ablation - inductively coupled plasma - mass spectrometry (LA-ICP-MS) of soil found that arsenic association with lead mineralogy could potentially explain why there was a gradient in arsenic loss across the experimental plots. Slurry and atmospheric inputs, and sward off-take had little impact on the soil arsenic mass-balance. The findings suggest that leaching loss down the soil profile was the mechanism of loss of arsenic. The applicability of the LTS experimental site arsenic findings to other soils is discussed, as is the implication for the global biogeochemical cycling of those soils., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Andrew Meharg reports funding was provided by Queen's University Belfast. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Propranolol (PRO) has been detected in water bodies worldwide, attributed to the incomplete removal by wastewater treatment processes. Although reports exist on the removal of PRO by wetland plants such as Phragmites communis, research on the impact of PRO on soil organic carbon (SOC) components in these plants' rhizospheres remains scarce. This investigation examined the impacts of 0.5 μg/L and 50 μg/L concentrations of PRO on the rhizosphere of P. communis over a 21-day laboratory experiment. PRO exposure slightly promoted root growth, notably enhancing fine root development at a lower concentration. A notable decrease in SOC content was observed in the PRO-treated samples: specifically, the proportion of mineral-associated organic carbon (MAOC) rose (from 47.90 % to 33.17 %), whereas the proportion of particulate organic carbon (POC) significantly declined following PRO treatment (from 52.10 % to 66.83 %). Moreover, Proteobacteria and Nitrospirae experienced significant promotion in the high-concentration samples while Bacteroidetes and Verrucomicrobia were inhibited. The metabolomic analysis demonstrated that glycine, serine, and threonine metabolism was the principal differential metabolic pathway in varying concentrations of PRO exposure. Additionally, across varying PRO concentrations, plant influence emerged as the predominant factor affecting POC alterations, whereas MAOC changes resulted from the synergistic interaction of plants and associated bacteria. The outcomes of this study mark a critical advancement towards a thorough assessment of PRO's impact on the rhizosphere of wetland plants, bearing significant ramifications for evaluating PRO's environmental effects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Soil Phosphorus (P) fixation and Arsenic (As) contamination pose significant challenges to agriculture and environmental health. Biochar has emerged as a promising soil amendment capable of enhancing P availability while immobilizing As. This review explored the mechanisms by which biochar influences P dynamics and As sequestration. Biochar enhances P availability by reducing fixation, stimulating P-solubilizing microorganisms, and gradually releasing the adsorbed P. Specific biochars, such as Mg-modified and La-modified types, demonstrate high P adsorption capacities, reaching up to 263 mg/g, while cerium and iron-modified biochars show As adsorption efficiencies up to 99 % under certain conditions. Biochar's surface functional groups are essential for P and As adsorption through mechanisms such as surface adsorption, ligand exchange, and inner-sphere complexation. The competitive adsorption between P and As is influenced by pH, biochar modification, and co-existing anions. Under acidic conditions, As shows a higher affinity for biochar, forming stable complexes with metal oxides like iron and aluminum. Biochars modified with calcium, magnesium, lanthanum, zinc, cerium, and iron demonstrate enhanced adsorption capacities. In neutral to alkaline conditions, calcium- and magnesium-modified biochars benefit P retention, while iron-modified biochar is preferable for As adsorption. Additionally, biochar promotes microbial activity and enzymatic processes that facilitate As transformation and P mineralization, enhancing overall soil health. These findings underscore biochar's dual role in increasing nutrient availability and reducing contaminant risks, making it a valuable tool for sustainable agriculture. Field-scale applications should be prioritized in future research to optimize biochar's impact on soil fertility and environmental remediation., Competing Interests: Declaration of competing interest The authors declare that they have no affiliations with or involvement in any organization or entity with any financial interest in the subject matter or materials discussed in this manuscript., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In recent decades, the menace of heavy metals to food security and human health has become a serious concern. Given its status as the primary provider of food globally, significant research has been done to ensure the safe cultivation of rice, particularly concerning the mitigation of heavy metal contamination. Therefore, this article focuses on the effects and poisoning mechanism of heavy metals, primarily cadmium, on rice. Here, we have discussed the absorption, translocation, and toxicity mechanism of cadmium in rice and the external factors, such as soil pH, organic matter, microorganisms, and climate change, associated with this pollution. It also discusses in detail the sources of heavy metal pollution and the countermeasures against their effects on rice, such as the use of nanoparticles, biochar, plant growth regulators, nutrient management, molecular approaches, tolerant genotypes, and associated genes/proteins. Lastly, a number of significant research prospects concerning heavy metals in rice fields were suggested for future investigation. This review serves as a crucial reference for addressing the issue of heavy metal contamination in paddy fields, ensuring the safe cultivation of rice, promoting environmentally friendly fish farming practices, and safeguarding future food security and human health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The use of plastics inevitably leads to (micro-)plastics entering and accumulating in the natural environment, affecting biodiversity, food security and human health. Currently, a comprehensive and universally applicable methodology to quantify microplastic accumulation in the natural environment is lacking. This study proposes an integrated biodegradation model that provides the possibility to examine and compare the microplastic formation and accumulation of different polymer types in diverse natural environments. The proposed model derives carbon mass flow streams from experimental mineralisation curves (CO 2 evolution) of polymers and predicts the concentrations and residence times of the different plastic states during their biodegradation processes. The model allows for the description of the accumulation potential of polymers, as the time-integrated concentration of microplastics present in the natural environment during a timeframe of 100 years after a polymer enters the natural environment. The model is applied to estimate the accumulation potential of three polymers with different biodegradation profiles in soil: polybutylene succinate (PBS), polylactic acid (PLA) and polyethylene (PE). It is demonstrated that the dimensionless accumulation potential of PBS in soil is near zero (between 3.0·10 -4 and 0.002) which corresponds to a potentially very low level of accumulation. On the other hand PE shows a near maximum value of 1 which corresponds to the almost completely non-biodegradable character of this polymer in soil. PLA exhibits a wide range of values in between that of PBS and PE which reflects its reported relatively slow biodegradation in soil. The proposed model can be used to guide material selection in product design by quantifying the microplastic accumulation of these different polymer types. To demonstrate its use, plastic candy wrappers and agricultural mulch films were selected as case studies. Both case studies show that high biodegradation rates can limit or prevent microplastic accumulation in soil., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Changes in the soil environment due to urbanization pose a challenge to predict the health risks from soil PAHs on a regional scale. The sources and distributions of PAHs in the soil of the Changsha-Zhuzhou-Xiangtan Urban Agglomeration in China were analyzed using positive matrix factorization (PMF), GIS mapping, and the Random Forest (RF) model to estimate the spatiotemporal variations in health risks. The measured concentration of PAHs in the soil ranged from 20.1 to 15,233.1 μg/kg with a mean of 493.2 μg/kg. PMF and diagnostic ratios identified the primary sources of soil PAHs as transportation and coal combustion (59.1 %), soil-air exchange processes (20.5 %), and petroleum products (20.4 %). Transportation and industrial coal combustion contributed to 81.9 % and 81.7 % of the total health risks to children and adults, respectively. Locations of major point sources were identified by PMF and GIS mapping and were distributed at the congestive overpasses in urban areas and industrial enterprises carrying out large-scale coal combustion. The RF model suggested an increase, by 33.2 %, of areas with ILCRs exceeding the risk threshold if the population increases by 50.0 % in 2035. Areas with a PD > 500 p/km 2 , RD > 2 km/km 2 , and DNS < 15 km pose a high probability of health risks on local residents. The integrated approach enhanced the reliability of apportioning sources and risk assessment, serving as a reference for early warnings and a basis for soil surveys in urban areas., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Zinc oxide nanoparticles (ZnONPs) are widely applied across multiple industries and ultimately accumulate in water and soil environments, raising significant concern about their toxicity to organisms in various ecosystems. While the effects of ZnONPs on microflora have been reported, their ecotoxicity to specific biogeochemical process and microbial activities and metabolic functions remains relatively unclear. In this study, a 56-day microcosmic experiment was conducted to explore the toxicity mechanism of ZnONPs (1000 mg kg -1 soil) on straw decomposition, soil organic carbon (SOC) mineralization, and changes in microbial activities and functions in agricultural soil with general wheat straw incorporation using the 13 C isotope tracer technique. The results demonstrated that straw incorporation increased the rate of CO 2 emission and promoted the straw decomposition. However, the presence of ZnONPs reduced the CO 2 release rates during incubation period although the rates were still higher than those under the control due to straw incorporation. CO 2 emissions from straw decomposition were dominant before the 7th day of incubation. After day 7, CO 2 emissions from the mineralization of original SOC became dominant with their contribution increasing from 17.52 % on day 7 to 60.20 % on day 56 under straw incorporation. ZnONPs affected soil carbon composition and straw decomposition by inhibiting enzyme activity and reducing the abundance of functional genes, indirectly impacting CO 2 release. Community Level Physiological Profiles (CLPP) showed ZnONPs reduced functional richness indices, including Shannon-Weiner index (H) and McIntosh index (U), and altered C substrate utilization patterns. This may be due to the direct toxicity of zinc ion (Zn 2+ ) released by ZnONPs to the soil bacterial community. The findings provide insights into the toxicity effects of emerging contaminants on carbon transformation from straw and SOC. Further investigations involving metabolomics are required to reveal the essential effects of ZnONPs on biogeochemical cycle of elements in agricultural soil., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Composting is a sustainable method for managing livestock manure, but the residual heavy metals and antibiotics in the compost pose can pose environmental risks when applied to land. Although many studies focus on occurrence and risk mitigation of heavy metals and antibiotics in manure compost land application, there is a lack of systematic analysis covering the entire chain from source to process and final disposal. Given this, this article provides a comprehensive review of the sources, migration, fate, risk assessment, and risk reduction of heavy metals and antibiotics contamination in land application of livestock manure compost for the first time. The main pollutants of concern are heavy metals, particularly Cu and Zn, and antibiotics such as quinolones, tetracyclines, and sulfonamides. The coexistence of these contaminants can easily trigger co-contamination, threatening soil ecosystems and human health. Risk reduction strategies, emphasizing the use of additives during composting and phytoremediation after land application, are discussed. Challenges remain in understanding the interactions between heavy metals and antibiotics and developing effective strategies for mitigating co-contamination. Furthermore, the paper proposes the future prospects on the interactions study and the simultaneous control strategy of heavy metals and antibiotics contamination. It is expected to promote the whole process management of livestock manure and the control of heavy metal-antibiotic co-contamination in the future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Combined effects of water management and agricultural organic waste return on selenium (Se) bioavailability and mechanisms in Se-enriched paddy soils remain unclear. We investigated the effects of continuous flooding (CF) and alternating wet and dry (AWD), two types (cotton straw biochar [BC] and sheep manure [SM]) and concentrations (10 and 50 g·kg -1 ) of organic amendments on soil Se bioavailability, bacterial community structure in naturally Se-enriched soils (1.69 mg·kg -1 ). Results showed that 10 g·kg -1 SM treatment was the most effective in increasing Se bioavailability, especially under AWD treatment, whereas BC treatment reduced it. Compared with CF treatment, AWD treatment increased the Se content of root surface iron plaque and rhizosphere affinity for Se, and promoted the conversion of soil weakly organic matter bound Se to soluble-Se and exchangeable-Se. BC and SM addition significantly altered soil solution Fe(II), dissolved organic carbon, and soil bacterial community structure and function, including sulfur-oxidizing bacteria (Thiobacillus) and Se-reducing bacteria (Pseudarthrobacter), under different water management regimes. Notably, these bacteria showed a significant correlation with bioavailable Se. The present study provides theoretical guidance for agronomic practices in Se-enriched paddy soils., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Selenium (Se) in soil is the primary source of human Se intake, and its content and bioavailability are influenced by soil physicochemical properties. However, the influence of soil physicochemical properties on Se enrichment and bioavailability in soil remains uncertain. Therefore, this study investigated 536 soil samples and their corresponding wheat grain samples collected from the oasis zone of Aksu Prefecture, located in northwest China. The Se content, spatial distribution, and bioaccumulation factor (BCF) in soil and wheat grains as well as soil Se fractions were examined, and the effects of soil physicochemical properties on Se enrichment and bioavailability were assessed. The results indicated that the mean Se content of soil (0.32 mg/kg) surpassed the national Se background level for Chinese soil by a factor of 1.10. The average Se content (0.13 mg/kg) in wheat grains met the national standard for Se-rich cereal products. The prediction model established using multiple linear regression showed that soil calcium carbonate (CaCO 3 ), organic matter (OM), cation exchange capacity (CEC), and electrical conductivity (EC) were the main physicochemical factors influencing Se enrichment in soil, accounting for 29 % of the variation. The main physicochemical factors affecting Se bioavailability were CaCO 3 , OM, and iron, and the main Se fractions were the exchangeable and humic acid-bound Se fractions, which together explain 12 % of the variance. Additionally, a structural equation model was employed to analyze the pathways and interactions of soil factors on soil Se enrichment and bioavailability. The results indicated that soil CaCO 3 and OM were the most critical factors affecting Se enrichment and bioavailability in soil. These findings can provide technical guidance for the cultivation and layout of Se-rich wheat in local and other similar regions around the world., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Bio-based fertilizers (BBFs) produced from organic waste contribute to closed-loop nutrient cycles and circular agriculture. However, persistent organic contaminants, such as per- and poly-fluoroalkyl substances (PFAS), polychlorobiphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), as well as polyaromatic hydrocarbons (PAHs) can be present in organic waste or be formed during valorization processes. Consequently, these hazardous substances may be introduced into agricultural soils and the food chain via BBFs. This study assessed the exposure of 84 target substances and extractable organic fluorine (EOF) in 19 BBFs produced from different types of waste, including agricultural and food industrial waste, sewage sludge, and biowaste, and through various types of valorization methods, including hygienization at low temperatures (<150 °C) as well as pyrolysis and incineration at elevated temperatures (150-900 °C). The concentrations in BBFs (ΣPFOS & PFOA: <30 μg kg -1 , Σ6PCBs: <15 μg kg -1 , Σ11PAHs: <3 mg kg -1 , Σ17PCDD/Fs: <4 ng TEQ kg -1 ) were found to be below the strictest thresholds used in individual EU countries, with only one exception (pyrolyzed sewage sludge, Σ11PAHs: 5.9 mg kg -1 ). Five BBFs produced from sewage sludge or chicken manure contained high concentrations of EOF (>140 μg kg -1 ), so monitoring of more PFAS is recommended. The calculated expected concentrations in soils after one BBF application (e.g. PFOS: <0.05 μg kg -1 ) fell below background contamination levels (PFOS: 2.7 μg kg -1 ) elsewhere in the literature. This was confirmed by the analysis of BBF-amended soils from field experiments (Finland and Austria). Studies on target legacy contaminants in sewage sludge were reviewed, indicating a general decreasing trend in concentration with an apparent half-life ranging from 4 (PFOS) to 9 (PCDD/Fs) years. Modelled cumulative concentrations of the target contaminants in agricultural soils indicated low long-term risks. Concentrations estimated and analyzed in cereal grains were low, indicating that exposure by cereal consumption is well below tolerable daily intakes., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Nicolas Estoppey reports financial support was provided by EU Horizon 2020 research and innovation program under grant agreement 818,309 (LEX4BIO). Emma R. Knight reports financial support was provided by EU Horizon 2020 research and innovation program, through the project ZeroPM (101036756). Ian Allan reports financial support was provided by EU Horizon 2020 research and innovation program, through the project ZeroPM (101036756). Goril Aasen Slinde reports financial support was provided by EU Horizon 2020 research and innovation program under grant agreement 818,309 (LEX4BIO). Kari Ylivainio reports financial support was provided by EU Horizon 2020 research and innovation program under grant agreement 818,309 (LEX4BIO). Alicia Hernandez-Mora reports financial support was provided by EU Horizon 2020 research and innovation program under grant agreement 818,309 (LEX4BIO). Hans Peter H. Arp reports financial support was provided by EU Horizon 2020 research and innovation program, through the project ZeroPM (101036756). Hans Peter H. Arp reports financial support was provided by Research Council of Norway, through the Miljøforsk project SLUDGEFFECT (NFR 302371). Gerard Cornelissen reports financial support was provided by EU Horizon 2020 research and innovation program under grant agreement 818,309 (LEX4BIO). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Atmospheric deposition plays a significant role in the introduction of trace metals into agricultural ecosystems; however, accurately determining its impact on the accumulation of metals in crops remains a challenge. Here, the contribution, absorption mode, and model prediction of atmospheric deposition to trace metal accumulation in soybean were investigated by a three-year full factorial atmospheric and soil exposure experiment near a large copper (Cu) smelter. The results showed that newly deposited (one-year atmospheric deposition) metals only accounted for 0.2 %-14 % of total soil pools, while they contributed 8 %-77 % of Cu and 14 %-84 % of lead (Pb) in soybean plants. Meanwhile, the extension of soil exposure time to atmospheric deposition (two- and three-year atmospheric deposition) did not lead to significant increase in the bioavailable fraction of Cu and Pb in soil plough horizon and the bioaccumulation in soybean tissues. This suggested that the newly atmospheric deposition during the growth period was the key source of Cu and Pb in soybean plants. Furthermore, foliar absorption was an important pathway for metal accumulation in aboveground tissues as evidenced by its relative high contributions in metal bioaccumulation, i.e., 17 %-62 %, 26 %-70 %, 19 %-75 %, and 20 %-46 % of Cu and Pb in stem, leaf, hull, and seed, respectively. Besides, two models were developed to predict the Cu and Pb concentrations in soybean seeds using multiple regression analysis with atmospherically deposited metals and soil metals as variables. Compared with models based on a single variable, these models significantly improved the prediction accuracy of Cu and Pb concentrations in soybean seeds (adjusted R 2  = 0.936 and 0.995). The model prediction results suggested that the threshold value of atmospherically deposited Pb to ensure the safe production of soybean was 17.7 mg/m 2 /year. This study offers new insights into the effective management of metal pollution in soybeans, focusing on atmospheric deposition and foliar absorption., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Research on the use of organic materials as soil amendments for the remediation of Cd-contaminated agricultural land exists. However, the mechanisms based on which organic materials affect the distribution and availability of Cd in soil aggregates remain unclear. Here, Cd-contaminated paddy soil and different bio-based materials were used for rice pot experiments. Rhizosphere soils were separated into six particle sizes. Cd fractions were analyzed with BCR sequential extraction and specific functional groups associated with Cd were characterized using XPS. We found that bio-based materials promoted the formation of large aggregates to different extents. Cd tended to be enriched in fine- and coarse-grained soil particles, which is mainly related to the soil organic matter. Bio-based materials reduced the relative content of the weak-acid extractable fraction and increased the relative content of the reducible fraction, resulting in soil Cd immobilization. Soil dissolved organic matter (DOM) was the key factor affecting the distribution and availability of Cd in soil aggregates and different organic matter and Cd-binding functional groups in aggregates altered the Cd availability in soil. The results provide insight and guidance for understanding the cadmium immobilization mechanism and screening appropriate materials in the remediation of agricultural land., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Wastewater treatment plants (WWTP) are recognized as major sources of microplastic (MP) particles in terrestrial environments, particularly in agricultural soils through biosolids application. While many reviews have focused on the distribution, detection, and mitigation of MPs in wastewater effluent to limit their discharge into oceans, our understanding of methods to mitigate biosolid contamination remains limited. This review focuses on methods for mitigating MPs contamination in biosolids at various intervention points, including sources, WWTP including the primary and secondary treatment stages where sludge is generated, and post-contamination. These methods are categorized as physical, physicochemical, and biological approaches, and their advantages and limitations are discussed. For instance, physicochemical methods, especially froth flotation, are cost-effective but are hindered by contaminants and reagents. Physical methods like microfibre filtration devices (MFD) are safe but their efficiency depends on the filter pore size and design. Biological methods, particularly microbial degradation, are limited by the varying efficiencies of microorganisms in breaking down MPs and the extended time required for their effective degradation. Other physical methods including dissolved air flotation, and ultrasonication already exist in WWTPs but may require retrofitting or optimization to enhance MP removal from biosolids. As each method inherently has limitations, the key to achieving MP-free biosolids, and thus preventing their release into agricultural soil, lies in integrating these methods through multi-coupling strategies., Competing Interests: Declaration of competing interest The authors declare no competing financial interests or personal relationships that could have influenced the work reported in this study., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Selenium (Se) volatilization represents a crucial component of the Se biogeochemical cycle in paddy systems. However, current existing methodologies for capturing volatile Se (VOSe) in high-humidity and low-volatility paddy systems are insufficient. This study developed an innovative approach to capture and quantify VOSe from soil and rice plants, such as DMSe (dimethylselenide) and DMDSe (dimethyldiselenide). Initially, the efficacy of preconcentration was enhanced by optimizing the sampling apparatus, which significantly reduced water vapour by 43.5 % and increased the Se concentration by 37.7 % within 6 h sampling. Subsequently, HPLC-ICPMS analysis refinements included the screening and optimizing chromatographic columns and mobile phases, achieving absolute detection limits of 1.2 pg and 1.4 pg for DMSe and DMDSe, respectively. For validation, VOSe were quantified in the paddy systems, with DMSe and DMDSe volatilized rates from soil measured at 16.55±9.94 ng·m -2 ·h -1 and 124.49±120.34 ng·m -2 ·h -1 , and from rice plants at 38.38±29.85 ng·m -2 ·h -1 and 72.54±94.66 ng·m -2 ·h -1 , respectively. Additionally, volatile H 2 Se and potential plant-based volatile organic Se species were found. This represents the first accurate and sensitive method for the in-situ capture of trace VOSe in high-humidity, low-volatility paddy systems, providing invaluable insights into the biogeochemical processes of Se volatilization., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Coking releases large quantities of multiple polycyclic aromatic hydrocarbons (PAHs), yet previous research has often focused on only a limited subset. This may not fully represent the overall risk posed by aromatic compounds. Here, a novel non-target analysis method was developed to identify more emerging PAHs and benzofuran derivatives. Beyond the 16 US Environmental Protection Agency priority PAHs (EPA PAHs), 56 emerging PAHs, 64 alkylated PAHs, and 32 furans were identified, with 69 compounds identified for the first time. The Σ 16 EPA PAHs, Σ 56 emerging PAHs, Σ 64 alkylated PAHs, and Σ 32 furans concentration ranges were 0.30-6910, 0.01-2187, 0.52-1649, and 0.06-588 μg/g, respectively. Emerging PAHs and furans had higher contributions in the plant area than the control area. Some PAHs and furans' concentrations were not significantly associated with the EPA PAHs; therefore, the EPA PAHs are insufficient to represent the totals PAHs concentration or risk. In the top 20 % of toxicological priority compounds, the emerging PAHs concentrations were 50 % of those of the EPA PAHs but posed 3.4 times the carcinogenic risk. Four of these compounds had higher carcinogenic risks than the EPA PAHs, while another nine had comparable risks. Thus, the risks of emerging PAHs cannot be ignored. Future monitoring and control of PAHs and furan emissions by the coking industry are highly recommended., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Understanding the modulation of paddy field irrigation to the migration of per- and polyfluoroalkyl substances (PFAS) at the water-soil interface is pivotal for the management of PFAS pollution in paddy soil and surrounding surface water environments. In flooded soils, soil organic matter was transformed into aromatic protein-like dissolved organic matter (DOM). Meanwhile, Na + , K + , and Mg 2+ were translocated into extracellular polymeric substances (EPS) under the catalysis of cation channel enzymes (p < 0.05), provided ion bridging for the binding of DOM and PFAS, and accelerated the accumulation of C4-C9 PFAS in overlying water (41.79-99.14 %). Short-chain PFAS's accumulation in soil solution of drought soils was stimulated by microorganisms secreting soluble microbial by-product-like DOM (53.15-97.96 %). Furthermore, PFAS's distribution in flood soils was dominated by bacterial denitrification and iron-reduction, whereas iron-oxidation and ammoxidation controlled that in drought soils. The transformation of organic carbon including CO and COC caused by irrigation-induced redox modulated PFAS cross-media translocation. Iron‑nitrogen redox in flooded paddy soils immobilized the PFAS's migration into overlying water (p < 0.05). Our findings have profound implications for PFAS's pollution control, surface water environmental protection, and rice production security in paddy fields., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Remediation of heavy metal (HM)-contaminated farmland has attracted much attention. Intercropping shows great potential in the remediation of HM-contaminated farmland and has been extensively studied. However, it remains uncertain how intercropping influences phytoremediation. In this study, a meta-analysis was performed to evaluate the effects of intercropping on plant growth, plant Cd uptake, residual soil Cd concentration, and the related impact factors. The results showed that compared with monocropping, intercropping decreased plant biomass (-13.0 %) and Cd uptake (-26.9 %), whereas it increased Cd translocation factor (5.23 %) and soil pH (2.74 %). However, intercropping decreased residual soil Cd concentration by -2.08 % under the conditions of low plant biomass and less Cd uptake. These indicate that phytoextraction may contribute little to soil Cd removal in intercropping, and the indirect effects of intercropping are more important than its direct effects. Intercropping effects were affected by experimental and environmental factors. In terms of decreasing residual soil Cd concentration, intercropping produced large effect under at least one of the following conditions: monocots-dicots combination, intercropping with hyperaccumulator, in the soil contaminated by industrial pollution-derived Cd, at soil Cd level of ≤10.0 mg/kg, in acid soil (pH ≤ 6.50), and at the medium experimental duration of 61-120 d. This study confirms that intercropping can accelerate the phytoremediation of Cd-contaminated soil, and indirect effects of intercropping may play important roles., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)