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Due to their significant environmental impact, there has been a gradual restriction of the production and utilization of legacy per- and polyfluoroalkyl substances (PFAS), leading to continuous development and adoption of novel alternatives. To effectively identify the potential environmental risks from crop consumption, the levels of 25 PFAS, including fourteen perfluoroalkyl acids (PFAAs), two precursor substances and nine novel alternatives, in agricultural soils and edible parts of various crops around a fluoride industrial park (FIP) in Changshu city, China, were measured. The concentration of ΣPFAS in the edible parts of all crops ranged from 11.64 to 299.5 ng/g, with perfluorobutanoic acid (PFBA) being the dominant compound, accounting for an average of 71% of ΣPFAS. The precursor substance, N-methylperfluoro-octanesulfonamidoacetic acid (N-MeFOSAA), was detected in all crop samples. Different types of crops showed distinguishing accumulation profiles for the PFAS. Solanaceae and leafy vegetables showed higher levels of PFAS contamination, with the highest ΣPFAS concentrations reaching 190.91 and 175.29 ng/g, respectively. The highest ΣAlternative was detected in leafy vegetables at 15.21 ng/g. The levels of human exposure to PFAS through crop consumption for various aged groups were also evaluated. The maximum exposure to PFOA for urban toddlers reached 109.8% of the standard value set by the European Food Safety Authority (EFSA). In addition, short-chained PFAAs and novel alternatives may pose potential risks to human health via crop consumption. [ABSTRACT FROM AUTHOR]

Approximately half of the global annual production of wastewater is released untreated into aquatic environments, which results in worldwide organic matter pollution in urban rivers, especially in highly populated developing countries. Nonetheless, information on microbial community assembly and assembly‐driving processes in organic matter–polluted urban rivers remains elusive. In this study, a field study based on water and sediment samples collected from 200 organic matter–polluted urban rivers of 82 cities in China and Indonesia is combined with laboratory water‐sediment column experiments. Our findings demonstrate a unique microbiome in these urban rivers. Among the community assembly‐regulating factors, both organic matter and geographic conditions play major roles in determining prokaryotic and eukaryotic community assemblies, especially regarding the critical role of organic matter in regulating taxonomic composition. Using a dissimilarity‐overlap approach, we found universality in the dynamics of water and sediment community assembly in organic matter–polluted urban rivers, which is distinctively different from patterns in eutrophic and oligotrophic waters. The prokaryotic and eukaryotic communities are dominated by deterministic and stochastic processes, respectively. Interestingly, water prokaryotic communities showed a three‐phase cyclic succession of the community assembly process before, during, and after organic matter pollution. Our study provides the first large‐scale and comprehensive insight into the prokaryotic and eukaryotic community assembly in organic matter–polluted urban rivers and supports their future sustainable management. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) pollutes 7.0 % of China's land area. This study examined the potential of Houttuynia cordata for Cd phytoremediation because of its ability to accumulate Cd in its growth matrix. H. cordata were planted in plastic pots filled with paddy field soils having low (LCd), medium (MCd), and high (HCd) Cd levels of 0.19, 0.69, and 2.91 mg/kg, respectively. After six months of growth, harvested plant parts were evaluated for Cd uptake and tolerance mechanisms. Metabolomics and metagenomics approaches were employed to investigate the soil rhizosphere mechanism. Results showed that the average plant biomass increased as soil Cd increased. The biomass Cd contents surpassed the allowable Cd limits for food (≤ 0.2 mg/kg) and medicinal uses (≤ 0.3 mg/kg). Cd contents were higher in H. cordata roots (30.59–86.27 mg/kg) than in other plant parts (0.63–2.90 mg/kg), with significantly increasing values as Cd soil level increased. Phenolic acids, lipids, amino acids and derivatives, organic acids, and alkaloids comprised the majority (69 in MCd vs HCd and 73 % in LCd vs HCd) of the shared upregulated metabolites. In addition, 13 metabolites specific to H. cordata root exudates were significantly increased. The top two principal metabolic pathways were arginine and proline metabolism, and beta-alanine metabolism. H. cordata increased the abundance of Firmicutes and Glomeromycota across all three Cd levels, and also stimulated the growth of Patescibacteria , Rozellomycota , and Claroideoglomus in HCd. Accordingly, H. cordata demonstrated potential for remediation of Cd-contaminated soils, and safety measures for its production and food use must be highly considered. [Display omitted] • High Cd soil enhanced H. cordata growth and increased Cd uptake. • H. cordata roots in high Cd soil exuded amino, phenolic, and organic acids. • Root secretion of acids elevated the dissolution and mobility of soil elements. • Rhizosphere microbes contributed to Cd uptake and passivation by H. cordata roots. • Arbuscular mycorrhizal fungi provided nutrients for H. cordata growth. [ABSTRACT FROM AUTHOR]

Summary: Acid mine drainage (AMD) generated by rare earth elements (REEs) deposits exploration contains high concentrations of REEs, ammonium and sulfates, which is quite different from typical metallic AMD. Currently, microbial responses and ecological functions in REEs‐AMD impacted rivers are unknown. Here, 16S rRNA analysis and genome‐resolved metagenomics were performed on microbial community collected from a REEs‐AMD contaminated river. The results showed that REEs‐AMD significantly changed river microbial diversity and shaped unique indicator species (e.g. Thaumarchaeota, Methylophilales, Rhodospirillales and Burkholderiales). The main environmental factors regulating community were pH, ammonium and REEs, among which high concentration of REEs increased REEs‐dependent enzyme‐encoding genes (XoxF and ExaF/PedH). Additionally, we reconstructed 566 metagenome‐assembled genomes covering 70.4% of identifying indicators. Genome‐centric analysis revealed that the abundant archaea Thaumarchaeota and Xanthomonadaceae were often involved in nitrification and denitrification, while family Burkholderiaceae were capable of sulfide oxidation coupled with dissimilatory nitrate reduction to ammonium. These indicators play crucial roles in nitrogen and sulfur cycling as well as REEs immobilization in REEs‐AMD contaminated rivers. This study confirmed the potential dual effect of REEs on microbial community at the functional gene level. Our investigation on the ecological roles of indicators further provided new insights for the development of REEs‐AMD bioremediation. [ABSTRACT FROM AUTHOR]

The tailings soil originating from an abandoned sulfur-iron mine in Sichuan Province, China, exhibits elevated concentrations of heavy metals (HMs) and possesses limited soil conservation capacity. Variability soil particle size fractions (PSFs) contributes to an increased risk of HMs ion migration. Existing research on HMs behavior has focused on the bulk soil scale, resulting in a dearth of comprehensive information concerning different particle sizes and colloid scales. We collected soil samples from upstream source (XWA), migration path (XWB), and downstream farmland (XWC) of an abandoned tailing and categorized into sand, silt, clay, colloid and dissolved, respectively. The investigation primarily aimed to elucidate the solid-liquid distribution trade-off strategies of soil HMs along migration pathway. Results show that PSFs composition predominantly influences HMs solid-liquid distribution. In the mining area, large particles serve as the principal component for HMs enrichment. However, along the migration pathway, the proportion of highly mobile fine particles increases, shifting HMs from solid to liquid phase. Furthermore, inorganic elements such as Mg, Al, and Fe influence on HMs distribution within PSFs through various reactions, whereas organic matter and glomalin-related soil protein (GRSP) also exert regulatory roles. Increasing the proportion of large particles can reduce the risk of HMs migration. [Display omitted] • The soils are mainly coarse particles, and the fine particles are accumulated downstream. • Heavy metals are mainly bound to coarse particles in mineral form. • Heavy metals in soil gradually shift from solid phase to liquid phase with the migration path. • Soil particle size fractions composition is the dominant factor of heavy metals trade-off strategy. • Inorganic matter is the main factor affecting the heavy metals selective distribution. [ABSTRACT FROM AUTHOR]

Intercropping technology and stabilizing materials are common remediation techniques for soils contaminated with heavy metals. This study investigated the feasibility of the Gynostemma pentaphyllum (G. pentaphy llum)/ Helianthus annuus L. (H. annuus) intercropping system on arsenic (As) contaminated farmland through field and pot experiments and the regulation of plant As absorption by the application of mixed stabilizing materials in this intercropping system. Field experiments demonstrated that intercropping with H. annuus increased the As concentration in G. pentaphyllum leaves to 1.79 mg kg−1 but still met the requirements of the national food standard of China (2 mg kg−1) (GB2762-2017). Meanwhile, G. pentaphyllum yield in the intercropping system decreased by 15.09%, but the difference was insignificant (P > 0.05). Additionally, the As bioconcentration (BCA) per H. annuus plant in the intercropping system was significantly higher than that in the monoculture system, increasing by 76.37% (P < 0.05). The pot experiment demonstrated that when granite powder, iron sulfate mineral, and "Weidikang" soil conditioner were applied to the soil collectively, G. pentaphyllum leaf As concentration in the intercropping system could be significantly reduced by 42.17%. Rhizosphere pH is the most crucial factor affecting As absorption by G. pentaphyllum in intercropping systems. When these three stabilizing materials were applied simultaneously, the As bioaccumulation (BCA) per H. annuus plant was significantly higher than that of normal intercropping treatment, which increased by 71.12% (P < 0.05), indicating that the application of these stabilizing materials significantly improved the As removal efficiency of the intercropping system. Dissolved organic carbon (DOC) concentration in the rhizosphere soil is the most pivotal factor affecting As absorption by H. annuus. In summary, the G. pentaphyllum - H. annuus intercropping model is worthy of being promoted in moderately As polluted farmland. The application of granite powder, iron sulfate mineral, and "Weidikang" soil conditioner collectively to the soil can effectively enhance the potential of this intercropping model to achieve "production while repairing" in the As polluted farmland. [Display omitted] • The As bioconcentration of H. annuus in intercropping system was significantly higher than that in monoculture system. • Application of mixed stabilizing materials significantly reduced the leaf As concentration of G. pentaphyllum. • Application of mixed stabilizing materials significantly increased the As bioconcentration of H. annuus. • pH and DOC content are the key factors that effecting the As uptake of G. pentaphyllum and H. annuus , respectively. [ABSTRACT FROM AUTHOR]

In the Pearl River Delta of China, many sites are likely contaminated with aniline in the soil and arsenic (As) in the groundwater because of a high As background level and the prevailing printing and dyeing industry. This study is to explore the remediation performance of thermally activated persulfate oxidation for the sites with these two contaminants, aniline and As. The As influence on the aniline degradation and vice versa are also systematically investigated. When the molar ratio of aniline to persulfate is 1: 4.65, over 85% of aniline can be degraded at 40 °C in 24 h, and 100 μg L−1 As(III) in solution can be completely adsorbed by the soil. A higher pH favored the aniline degradation but disfavored the As(III) oxidation. Due to the strong buffer capacity of the soil, aniline in the soil could be more quickly degraded than those in the solution. The As(III), however, seem more easily oxidized in the absence of soil. The coexisting Fe2+ can substantially improve As(III) oxidation and immobilization, although the dilute Fe2+ solution may suppress the aniline degradation. The presence of aniline severely inhibited the As(III) oxidation and adsorption, likely due to the competition for the generated free radicals and the adsorption sites on the soils. In contrast, the existing As(III) has a slight effect on aniline degradation. These findings are believed to provide the theoretical basis for the remediation of aniline-arsenic contaminated sites. [Display omitted] • A high pH favors aniline degradation by persulfate but disfavors As(III) oxidation. • Aniline in the soil can be faster degraded than in a solution without a buffer. • Fe2+ can improve As(III) oxidation by persulfate and immobilization. • Aniline severely inhibits As(III) oxidation and delays As(V) adsorption. [ABSTRACT FROM AUTHOR]

Rare earth elements sources in China have been overexploited and have caused serious soil pollution. The hyperaccumulator Dicranopteris dichotoma was discovered to have the ability to remove rare earth elements from contaminated soil and was widely planted as part of the remediation process for rare earth elements contaminated soil. Therefore, abundant hazardous Dicranopteris dichotoma biomass containing a high concentration of rare earth elements was generated. However, treatment methods for Dicranopteris dichotoma have not been previously investigated. In this paper, the eco-friendly technology of vacuum-pyrolysis-condensation was proposed for disposing the biomass of this fern, it was employed to change biomass accumulated with rare earth elements in to chemical resource. Ethylene oxide was the main component of the chemical resources, constituting 49.4 wt%. However, no ethylene oxide was detected in the pyrolytic products from non-accumulated biomass. The residual ash contained 6160 mg kg−1 of rare earth elements and was suggested as a rich 'bio-ore' of rare earth elements. No hazardous wastes were produced in the reclamation of these hyperaccumulators. We concluded that rare earth elements strongly influenced the pyrolysis process of dicranopteris dichotoma biomass and caused the generation of ethylene oxide. This paper takes the vacuum-pyrolysis-condensation of rare earth elements accumulated Dicranopteris dichotoma as the guidance, in order to attract more attention and develop more eco-friendly disposal technologies for hyperaccumulator biomass from the remediation process of contaminated soil, recovering the biomass resources and realized its high value. Image 1 • Rare earth elements (REEs) has caused serious soil pollution in China. • Quantities of REEs were accumulated in D. dichotoma in the remediation process. • A new technology to recover REEs from hyperaccumulator biomass was developed. • Higher yield of ethylene oxide was produced from contaminated D. dichotoma. [ABSTRACT FROM AUTHOR]

The application of neonicotinoid insecticides (NEOs) has increased dramatically in the world since being introduced in 1990s, yet the extent of human exposure and potential health risk is not fully unraveled. In this study, the residues were analyzed of 16 NEOs and their metabolites in 205 commercial cow milk samples circulating in Chinese market. All the milk samples contained at least one quantified NEO, and over 90% of samples contained a cocktail of NEOs. Acetamiprid, N -desmethyl acetamiprid, thiamethoxam, clothianidin and imidaclothiz were the most commonly detected analytes with detection frequencies of 50–88% and medians of 0.011–0.038 ng/mL in milk. Geographical origin was an important factor to influence abundances and levels of NEOs contamination in milk. Chinese local milk bore a significant higher risk from NEOs contamination than the imported milk. In China, the northwest presented the greatest concentrations of the insecticides relative to the north or south. Organic farming, ultra heat treatment and skimming could significantly reduce levels of NEOs contamination in milk. A relative potency factor method was used to evaluate estimated daily intake of NEO insecticides, and found the children had 3.5–5 times higher exposed risk via milk ingestion than the adults. The high frequency of NEOs detection in milk offers us a snapshot of the ubiquity of NEOs in milk, with possible health implications especially for children. [Display omitted] • Over 90% of the cow milk samples contained more than one NEO insecticides. • Compounds of ACE, N-dm-ACE, THX, CLO and IMZ were found at DFs of 50–88%. • The northwest China bore a higher risk from the milk NEOs contamination. • Organic farming, ultra heat treatment and skimming can reduce milk NEO residues. • Children had 3.5–5 times greater exposed risk via milk ingestion than adults. [ABSTRACT FROM AUTHOR]

Mining activities in metal mine areas cause serious environmental pollution, thereby imposing stresses to soil ecosystems. Investigating the ecological pattern underlying contaminated soil microbial diversity is essential to understand ecosystem responses to environment changes. Here we collected 624 soil samples from 49 representative metal mines across eastern China and analyzed their soil microbial diversity and biogeographic patterns by using 16 S rRNA gene amplicons. The results showed that deterministic factors dominated in regulating the microbial community in non-contaminated and contaminated soils. Soil pH played a key role in climatic influences on the heavy metal-contaminated soil microbial community. A core microbiome consisting of 25 taxa, which could be employed for the restoration of contaminated soils, was identified. Unlike the non-contaminated soil, stochastic processes were important in shaping the heavy metal-contaminated soil microbial community. The largest source of variations in the soil microbial community was land use type. This result suggests that varied specific ecological remediation strategy ought to be developed for differed land use types. These findings will enhance our understanding of the microbial responses to anthropogenically induced environmental changes and will further help to improve the practices of soil heavy metal contamination remediation. [Display omitted] • Deterministic and stochastic assembly were vital in shaping the polluted community. • Soil pH played a key role in climatic influences on the soil microbial community. • High variation of available heavy metal would lead to stochastic assembly. • Different land use type of soils would generate disparate co-occurrence patterns. [ABSTRACT FROM AUTHOR]

[Display omitted] Bisphenol S (BPS) and its 11 emerging analogues were investigated in 325 urine samples from five occupational populations in South China. Besides BPS, ten emerging BPS analogues were newly identified and detected in the urine. It should be noted that urinary concentrations of dominant BPS analogues of 2,4′-bis(hydroxyphenyl)sulfone (2,4-BPS), bis(3-allyl-4-hydroxyphenyl)sulfone (TGSA) and diphenylsulfone (DPS) were 1.1–2.3 times higher than that of BPS, with overall detection frequencies at 74–91 %. The median sum concentrations of the target 12 bisphenols (ng/mL) were found highest in urine from cashiers (1.12), followed by water plant staffs (0.994), teachers (0.552), doctors (0.408) and power plant staffs (0.333). The composition profile of the urinary dominant bisphenols was occupational-dependent, with 2,4-BPS accounting for 45–73 % in cashiers and power plant staffs, and with DPS and TGSA for 74–82 % among doctors, teachers and water plant staffs. Significant correlations were found among the most frequently detected bisphenols in cashiers, indicating their common application and emission pathways. The median exposures based on estimated daily intakes (EDIs, ng/kg bw/day) for the 12 bisphenols in cashiers and water plant staffs (31.6–35.6) were 1.8–3.4 times higher than those of teachers, doctors and power plant staffs (10.6–17.5). This is the first study to identify multiple emerging BPS analogues in urine from occupational populations, especially cashiers and water plant staffs. [ABSTRACT FROM AUTHOR]

Water resource shortage and arsenic (As) water pollution are threatening human food security. Using As micro-polluted water for agricultural production may alleviate the water resource shortage situation after solving the As problem. In situ formed hydrous titanium oxide possesses much higher As immobilization potential than purchased TiO 2 because of its higher specific surface area and more abundant active hydroxyl group, which is proposed to reduce the As uptake of aquatic vegetables planted in As micro-polluted water. Herein, TiOSO 4 solution, which can hydrolyze into hydrous titanium oxide during dilution in water, was used as a new water amendment to realize in situ As immobilization in lake water (100 μg-As/L) during cultivation of water spinach. We found that TiOSO 4 could immobilize trace level As with its dosage as the main factor influencing the efficiency through response surface analysis. A low dosage TiOSO 4 treatment of 0.5 mg/L could reduce the As content in the edible part from 0.64 to 0.40 mg/kg, which satisfied the vegetable As standard of China (0.5 mg/kg). The shoot As content was negatively related to the used TiOSO 4 dosage and could be further reduced to 0.16 mg-As/kg at a dosage of 4 mg/L TiOSO 4 , while the health risk index of eating water spinach could be reduced by 75% (from 1.6 to 0.4). Therefore, TiOSO 4 is a useful in situ As immobilization reagent during cultivation of water spinach and may possibly be used in the production of other aquatic vegetables. In situ TiOSO 4 treatment may be an effective and facile strategy for the agricultural utilization of As micro-polluted surface water, which can alleviate the shortage on safe agricultural water resource in the context of widespread water micro-pollution. [Display omitted] • TiOSO 4 removed trace arsenic efficiently from lake water via coagulation. • TiOSO 4 -treated lake water was used for water spinach cultivation. • TiOSO 4 treatment did not affect the yield of water spinach. • 4 mg/L TiOSO 4 decreased As concentration in water spinach edible part by 75%. • In situ TiOSO 4 treatment is a facile strategy to utilize As micro-polluted water. [ABSTRACT FROM AUTHOR]

• Prokaryotes and fungi responded differently to mining pollution and seasonal changes. • Fungal community network was more stable than prokaryotic community. • Stochastic processes are more important for fungal community than prokaryotic community. • Stochastic processes of microbiota are promoted when the pollution was alleviated. Ion-adsorption rare earth element (REE) deposits are the main reservoirs of REEs worldwide, and are widely exploited in South China. Microbial diversity is essential for maintaining the performance and function of mining ecosystems. Investigating the ecological patterns underlying the REE mine microbiome is essential to understand ecosystem responses to environmental changes and to improve the bioremediation of mining areas. We applied 16S rRNA and ITS gene sequence analyses to investigate the composition characteristics of prokaryotic (bacteria, archaea) and fungal communities in a river impacted by REE acid mine drainage (REE-AMD). The river formed a unique micro-ecosystem, including the main prokaryotic taxa of Proteobacteria, Acidobacteria, Crenarchaeota , and Euryarchaeota , as well as the main fungal taxa of Ascomycota, Basidiomycota , and Chytridiomycota. Analysis of microbial diversity showed that, unlike prokaryotic communities that responded drastically to pollution disturbances, fungal communities were less affected by REE-AMD, but fluctuated significantly in different seasons. Ecological network analysis revealed that fungal communities have lower connectivity and centrality, and higher modularity than prokaryotic networks, indicating that fungal communities have more stable network structures. The introduction of REE-AMD mainly reduced the complexity of the community network and the number of keystone species, while the proportion of negative prokaryotic–fungal associations in the network increased. Ecological process analysis revealed that, compared to the importance of environmental selection for prokaryotes, stochastic processes might have contributed primarily to fungal communities in REE mining areas. These findings confirm that the different assembly mechanisms of prokaryotic and fungal communities are key to the differences in their responses to environmental perturbations. The findings also provide the first insights into microbiota assembly patterns in REE-AMD and important ecological knowledge for the formation and development of microbial communities in REE mining areas. [Display omitted] [ABSTRACT FROM AUTHOR]

• Four distinct archaea were enriched in rare earth element (REE) mine drainage. • Archaea represented a considerable fraction (up to 40%) of prokaryote community. • Archaea significantly contributed to N and S cycling in REE mine drainage. • Metabolic network and genetic interactions might be crucial in niche adaptation of archaea. Microbial communities play crucial roles in mine drainage generation and remediation. Despite the wide distribution of archaea in the mine ecosystem, their diversity and ecological roles remain less understood than bacteria. Here, we retrieved 56 archaeal metagenome-assembled genomes from a river impacted by rare earth element (REE) mining activities in South China. Genomic analysis showed that archaea represented four distinct lineages, including phyla of Thaumarchaeota, Micrarchaeota, Nanoarchaeota and Thermoplasmata. These archaea represented a considerable fraction (up to 40%) of the total prokaryote community, which might contribute to nitrogen and sulfur cycling in the REE mine drainage. Reconstructed metabolic potential among diverse archaea taxa revealed that archaea were involved in the network of ammonia oxidation, denitrification, sulfate redox reaction, and required substrates supplied by other community members. As the dominant driver of ammonia oxidation, Thaumarchaeota might provide substrates to support the survival of two nano-sized archaea belonging to Micrarchaeota and Nanoarchaeota. Despite the absence of biosynthesis pathways for amino acids and nucleotides, the potential capacity for nitrite reduction (nirD) was observed in Micrarchaeota , indicating that these nano-sized archaea encompassed diverse metabolisms. Moreover, Thermoplasmata , as keystone taxa in community, might be the main genetic donor for the other three archaeal phyla, transferring many environmental resistance related genes (e.g., V/A-type ATPase and Vitamin B12-transporting ATPase). The genetic interactions within archaeal community through horizontal gene transfer might be the key to the formation of archaeal resistance and functional partitioning. This study provides putative metabolic and genetic insights into the diverse archaea taxa from community-level perspectives, and highlights the ecological roles of archaea in REE contaminated aquatic environment. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A recovery process of REEs in the ash of hyperaccumulator D. linearis was designed. • The ashes contained 3 wt% REEs (mainly La, Ce, Nd and Pr) and 6.5 wt% Al. • The bio-ore was enriched to 14 wt% REEs by an alkaline leaching step. • Mild acidic leaching (pH 4.8, 25 °C) was proven feasible to recover REEs in solution. Hyperaccumulator plants are new alternative sources for elements of interest e.g. , nickel, rare-earth elements (REEs), as concentrations in their aerial parts are higher than in common low-grade ores. The fern Dicranopteris linearis naturally grows on former mine tailings in Southern China and is classified as a REE hyperaccumulator. The efficient recovery of REEs is fundamental to ensure economic viability and to limit the environmental impact of the process. This study presents a novel approach for the treatment of the Dicranopteris biomass after incineration to ash to drastically improve the "bio-ore" grade and to generate heat. Ash structure and composition is described, and challenges for efficient recovery of REEs are discussed. A pre-processing step, aiming at rendering the REEs available for extraction, was designed to dissolve aluminum (Al) using concentrated sodium hydroxide (6 M) at an average temperature (80 °C). The operating parameters were investigated through experiment methodology design and parametric studies to build an empirical model. Additional experiments revealed that the formation of insoluble aluminosilicate compounds limited the removal of aluminium. Rinsing the REE-rich residue proved to be effective to increase the REE concentration and was carefully designed. Subsequently, the REEs were extracted under mildly acidic conditions using nitric acid (25 °C, pH 4.8), producing a valuable solution devoid of aluminium and containing 74% of the REEs. [ABSTRACT FROM AUTHOR]

• Heavy metal risks addressed by total burdens differed from their availabilities. • Cd and As were identified as major pollutants though pollution degree varied. • Soil properties, predominantly pH, significantly affected metal availability. • Climate would impact soil pH and further affect metal availability on large scale. China exemplifies the serious and widespread soil heavy metal pollution generated by mining activities. A total of 420 soil samples from 58 metal mines was collected across Eastern China. Total and available heavy metal concentrations, soil physico-chemical properties and geological indices were determined and collected. Risk assessments were applied, and a successive multivariate statistical analysis was carried out to provide insights into the heavy metal contamination characteristics and environmental drivers of heavy metal availability. The results suggested that although the degrees of pollution varied between different mine types, in general they had similar contamination characteristics in different regions. The major pollutants for total concentrations were found to be Cd and As in south and northeast China. The availability of Zn and Cd is relatively higher in south China. Soil physico-chemical properties had major effect on metal availability where soil pH was the most important factor. On a continental scale, soil pH and EC were influenced by the local climate patterns which could further impact on heavy metal availability. Enlightened by this study, future remediation strategies should be focused on steadily increasing soil pH, and building adaptable and sustainable ecological system to maintain low metal availabilities in mine site soils. [ABSTRACT FROM AUTHOR]

• Quantities of resin particles generated from waste printed circuit boards were dumped on soil at Qingyuan city of China. • There is little information about soil pollution caused by the dumped resin particles. • This paper presented the ecological destroy of soil when the resin particles were deposited on soil surface. About 0.8 million tons of resin particles, which were generated from the recovery of waste printed circuit boards, were dumped on soil at Qingyuan city of China. Resin particles not only belong to micro plastic but also contain brominated flame retardants and heavy metals. There is little information about soil pollution caused by the dumped resin particles. This study found resin particles would transfer from soil surface into soil at least 10 mm downward for six months. Average content of bromine in soil within 10 cm exceeded 2500 mg/kg. The highest content of Pb, Zn, and Cu was 3450, 1143 and 1450 mg/kg, which were approximately 6.9, 2.3 and 3.6 times as much as Grade Ⅲ soil standard of China. Micro plastic, brominated flame retardants, and heavy metals made significant effects on soil bacterial community. Bacterial diversity was destroyed and the number of resistant bacteria increased obviously such as Acinetobacter , Pseudomonas and Paracoccus. This paper presented the ecological destroy of soil when the resin particles were deposited on soil surface. It also suggested the government to urgently manage the resin particles produced in the recovery of waste printed circuit boards. [ABSTRACT FROM AUTHOR]

Mercury (Hg) mining activities are an important anthropogenic source of atmospheric Hg. The Xunyang Hg mine located in Shaanxi Province is the largest active Hg producing centre in China. To understand the biogeochemical processes of atmospheric Hg through Hg mining activities, six groups of experimental pots were carefully designed to investigate the effect of Hg mining activities on Hg contamination from atmospheric deposition in the local surface soils. Based on the variations of Hg in the soil from the experimental pots, the deposition flux and loading of Hg in the Xunyang Hg mining district were investigated. The results showed that the average concentration of total gaseous mercury (TGM) as high as 193 ± 122 ng m−3 was observed in the ambient air, which was orders of magnitude higher than that in remote areas. The average deposition flux and annual loading of atmospheric Hg were 72 mg m−2 y−1 and 10 t y−1, respectively. The dominant atmospheric Hg deposition is within a distance range of 6.0–12 km from the Hg retorting facility, accounting for approximately 85% of the total Hg loading. After 14 months of exposure, total mercury (THg) concentrations in the soil from the experimental pots increased 0.35–9.5 times, and the highest concentrations of methylmercury (MeHg) (3.7 ± 2.9 μg kg−1) in soil were observed in February. Concentrations as high as 643 μg kg−1 THg and 13 μg kg−1 MeHg in rice were observed in the second experimental year. Elevated concentrations of both THg and MeHg in rice indicated that the newly deposited atmospheric Hg was bioavailable, readily methylated, and taken up by rice, suggesting that the ongoing Hg mining activities cause serious Hg contamination in the soil-rice ecosystem and posed a threat to local residents in the Xunyang Hg mining area. Image 1 • Cinnabar retorting causes significant Hg emissions into the surrounding environment. • Approximately 85% of the TGM emitted from the Hg smelter is deposited within a distance of 6.0–12 km. • The newly deposited TGM is bioavailable, readily methylated, and easily taken up by rice. [ABSTRACT FROM AUTHOR]

Miscanthus is a common pioneer plant with abundant genetic variation in abandoned mines in southern China. However, the extent to which genetic differentiation among species modulates rhizosphere bacterial communities remains unclear. Miscanthus samples were collected from 26 typical abandoned heavy-metal mines with different soil types in southern China, tested using 14 pairs of simple sequence repeats (SSR) primers, and classified into two genotypes based on Nei's genetic distance. The structure and diversity of rhizosphere bacterial communities were examined using 16 S rRNA sequencing. The results showed that among the factors affecting the rhizosphere bacterial community structure of Miscanthus samples, the role of genotype was not significant, and geographical conditions were the most important factors, followed by pH and total organic carbon (TOC). The process of rhizospheric community assembly varied among different genotypes; however, the recruited species and their abundances were similar. Collectively, we provided an approach based on genetic differentiation to quantify the relative contribution of genotypes to the rhizosphere bacterial community, demonstrating that genotypes contribute less than soil conditions. Our findings provide new insights into the role of host genetics in the ecological processes of plant rhizosphere bacterial communities in abandoned mines and provide theoretical support for microbe-assisted phytoremediation., 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.)

Endocrine-disrupting chemicals (EDCs) are pervasive in the environment, prompting significant public concern regarding human exposure to these pollutants. In this study, we analyzed the levels of various endocrine-disrupting compounds, including parabens (PBs), benzophenones (BzPs), triclocarban (TCC) and triclosan (TCS), across 565 urine samples collected from residents of South China. All 11 target chemicals were detected at relatively high frequencies (41-100%), with the most prevalent ones being 3,4-dihydroxybenzoic acid (5.39 ng/mL), methyl-paraben (5.12 ng/mL), ethyl-paraben (3.11 ng/mL) and triclosan (0.978 ng/mL). PBs emerged as the most predominant group with a median concentration of 32.2 ng/mL, followed by TCs (sum of TCC and TCS, 0.998 ng/mL) and BzPs (0.211 ng/mL). Notably, urinary concentrations of PBs in adults were significantly higher (p < 0.01) compared to children, while BzPs and TCs were elevated in children (p < 0.001). The increased presence of BzPs and TCs in children is a cause for concern, given their heightened sensitivity and vulnerability to chemicals. Significant correlations were found between urinary target compounds and demographic factors, including gender, age and body mass index. Specifically, females, younger adults (18 ≤ age ≤ 35) and individuals with under/normal weight (16 ≤ BMI ≤ 23.9) were found to have higher exposure levels to EDCs, as indicated by the median values of their estimated daily intakes. Despite these higher levels still being lower than the acceptable daily intake thresholds, the health risks stemming from simultaneous exposure to these EDCs must not be overlooked., 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 Ltd. All rights reserved.)

In North China, iodine-rich groundwater has been extensively studied, but few in South China. This study aimed to investigate the characteristics of iodine-rich groundwater in South China and identify potential contamination sources. The results revealed that the average concentration of iodine in groundwater was 890 µg/L, with a maximum concentration of 6350 µg/L, exceeding the permitted levels recommended by the World Health Organization (5-300 µg/L). Notably, the enrichment of iodide occurred in acidic conditions (pH = 6.6) and a relatively low Eh environment (Eh = 198.4 mV). Pearson correlation and cluster analyses suggested that the enrichment of iodide could be attributed to the intensified redox process involving Mn(II), iodine (I 2 ), or iodate (IO 3 - ) in the soil. The strong affinity between Mn(II) and I 2 /IO 3 - facilitated their interaction, resulting in the formation and mobilization of I - from the soil to the groundwater. Leaching experiments further confirmed that reducing substances (such as sodium sulfides, ascorbic acids, and fulvic acids) in the soil with low dissolved oxygen (DO) levels (< 1.0 mg/L) enhanced the dissolution of iodine species. Conversely, higher DO content (> 3.8 mg/L) promoted the oxidation of I - into I 2 enrichment in groundwater in South China, and emphasizes the significance of the redox reactions involving Mn(II) and I 3 - , leading to its stabilization. This research provides new insights into the characteristics and mechanisms of I - enrichment in groundwater in South China, and emphasizes the significance of the redox reactions involving Mn(II) and I 2 /IO 3 - , as well as the influence of soil properties in regulating the occurrence and transportation of iodine species within groundwater systems., 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 © 2023. Published by Elsevier B.V.)

Urban blue-green infrastructure (BGI) offers a multitude of ecological advantages to residents, thereby playing a pivotal role in fortifying urban resilience and fostering the development of climate-resilient cities. Nonetheless, current research falls short of a comprehensive analysis of BGI's overall potential for carbon reduction and its indirect carbon reduction impact. To fill this research gap, we utilized the integrated valuation of ecosystem services and trade-offs model and remote sensing estimation algorithm to quantify the direct carbon sequestration and resultant indirect carbon reduction facilitated by the BGI within the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) (China). To identify the regions that made noteworthy contributions to carbon offsets and outliers, spatial autocorrelation analysis was also employed. The findings of this study reveal that in 2019, the BGI within the study area contributed an overall carbon offset of 1.5 × 10 8 t·C/yr, of which 3.5 × 10 7 and 11.0 × 10 7 t·C/yr were the result of direct carbon sequestration and indirect carbon reduction, respectively. The GBA's total CO 2 emissions were 1.1 × 10 8 t in 2019. While the direct carbon sequestration offset 32.0% of carbon emissions, the indirect carbon reduction mitigated 49.9% of potential carbon emissions. These results highlight the critical importance of evaluating BGI's indirect contribution to carbon reduction. The findings of this study provide a valuable reference for shaping management policies that prioritize the protection and restoration of specific areas, thereby facilitating the harmonized development of carbon offset capabilities within urban agglomerations.

A bacterium, designated strain T21 T , that is non-motile, rod-shaped, and formed pale white colonies, was isolated from the sludge of a wastewater treatment plant's secondary sedimentation tank in China. Strain T21 T could grow at 20-40 °C (optimum growth at 30 °C), pH 3.0-10.0 (optimum growth at pH 5.0) and in the presence of 0-8.0% (w/v) NaCl (optimum growth at 2.0%). Based on phylogenetic analysis of 16S rRNA gene sequences and genome sequences, the isolate belongs to the genus Tessaracoccus in the phylum Actinomycetota. It exhibited a close relationship with Tessaracoccus palaemonis J1M15 T , Tessaracoccus defluvii LNB-140 T , Tessaracoccus flavescens SST-39 T , and Tessaracoccus coleopterorum HDW20 T . The 16S rRNA gene sequence similarities are 99.8%, 97.9%, 97.9%, and 97.8%, respectively. The major cellular fatty acids were anteiso-C 15:0 and C 16:0 . The main respiratory quinone was MK-9(H 4 ). The polar lipids included phosphatidylglycerol, diphosphatidylglycerol, glycolipid, and phospholipid. Genome annotation of strain T21 T predicted the presence of 2829 genes, of which 2754 are coding proteins and 59 are RNA genes. The genomic DNA G+C content was 69.2%. Based on the results of phylogenetic, phenotypic, chemotaxonomic, and genotypic analyses, we propose the name Tessaracoccus lacteus sp. nov. for this novel species within the genus Tessaracoccus. The type strain is T21 T (=CCTCC AB 2023031 T  = KCTC 49936 T )., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

A Gram-stain-negative, rod-shaped, non-motile, catalase-positive, denitrifying bacterium, designated strain Y-1 T , was isolated from an aeration tank of a sewage treatment plant in China and characterized using polyphasic taxonomic approaches. Strain Y-1 T could grow at 10-37 °C (optimum 25 °C), at pH 5.0-10.0 (optimum 7.0) and in the presence of 0-3.0% (w/v) NaCl (optimum 0.5%). The phylogenetic tree based on the 16S rRNA gene sequences revealed that strain Y-1 T was a member of genus Diaphorobacter, and showed the highest sequence similarities with Diaphorobacter oryzae RF3 T (97.50%), Diaphorobacter nitroreducens NA10B T (97.38%) and Diaphorobacter aerolatus 8604S-37 T (96.56%). In terms of carbon source utilization and enzyme activities, strain Y-1 T was significantly different from its similar strains. The major respiratory quinone was Q-8, and the main polar lipid was phosphatidylethanolamine. Comparative genomic analysis of strain Y-1 T and other Diaphorobacter species was conducted to explore the mechanisms underlying the differences among these strains. Strain Y-1 T encoded 3957 genes, consisting of 3813 protein-coding genes and 144 RNA coding genes, and encoded 652 enzymes with 31 unique enzymes compared with other related species. The DNA G + C content was 69.95 mol%. Strain Y-1 T exhibited 41.71% DNA-DNA relatedness and 95% ANIb with the most related type strains.On the basis of the evidence presented from polyphasic analysis, strain Y-1 T was suggested as a novel species within the genus Diaphorobacter, for which the name Diaphorobacter limosus sp. nov. is proposed, with the type strain Y-1 T (= KCTC 92852 T  = CCTCC AB 2023032 T )., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Emerging bisphenol S analogues (BPSs) have gained their application perspectives to replace bisphenol A (BPA) and BPA analogues (BPAs). However, the extent of human exposure and potential health risk from BPSs is rarely known yet. We hypothesized that children living in Shantou, China, a well-known e-waste recycling city, may expose to emerging BPSs together with BPA and BPAs. In this study, BPA, six commonly used BPAs and 11 emerging BPSs were determined simultaneously in 240 urine samples collected from children residing in Shantou. BPA, BPS, bisphenol F, bisphenol AF and three BPSs of 2,4'-bis(hydroxyphenyl)sulfone, 4-((4-(allyloxy)phenyl)sulfonyl)phenol and diphenylsulfone (DPS) were the urinary predominant bisphenols with detection frequencies of 67-100% in the children. BPA was found at the highest median concentration (3.36 µg/g creatinine) followed by BPS (0.313) and DPS (0.187). It is interesting to find that the girls and children in the younger group (2 ≤ age < 5) had consistently higher concentrations of the seven dominant bisphenols than the boys and these of the older group (5 ≤ age ≤ 10), respectively. The children with under/overweight suffered higher burdens of bisphenol exposure based on medians of estimated daily intakes. Association analysis results indicated that the Shantou children exposed themselves to multiple BPSs along with BPA and BPAs from assumed consumer products and/or contaminated environments., 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 © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Phytomining technology cultivates hyperaccumulator plants on heavy metal contaminated soils, followed by biomass harvesting and incineration to recover valuable metals, offering an opportunity for resource recycling and soil remediation. Large areas of ultramafic soils, naturally rich in nickel (Ni), are present in numerous places around the world. As an environmentally friendly and cost-effective soil remediation technology, phytomining has a broad application prospect in such areas and thus has attracted great attention from global researchers. The key processes of phytomining include: (1) high-selectivity response of hyperaccumulator plants to Ni the underlying mechanisms involved in the rhizosphere; (2) underlying mechanisms of high-efficiency uptake and translocation of Ni in hyperaccumulators; and (3) resource recycling of high-added value Ni products from the Ni-rich bio-ore of hyperaccumulators. In recent 30 years, phytomining practices have successfully carried out in United States, Albania and Malaysia. However, the research and application of this technology in China are still in the fledging stage. This paper reviews the key processes and research progress of phytomining, and points out the bottleneck, to provide theoretical basis and technical guidance for phytomining.

To explore the effect of different biochars on Cassia alata L. growth and heavy metal immobilization in multi-metal mine tailings, a 100-day pot experiment was conducted. Three biochars derived from Hibiscus cannabinus core (HB), sewage sludge (SB) and chicken manure (MB), were added to mine tailings at rates of 0.4%, 1% and 3% ( w / w ). The results showed that the root biomass, shoot biomass, plant height and root length were 1.2-2.8, 1.7-3.2, 1-1.5 and 1.6-3.3 times of those in the control group, respectively. Pb, Zn, Cu, Cd and As contents in the shoot decreased by 63.9-89.5%, 46.9-66.0%, 32.7-62.4%, 40.4-76.4% and 54.9-77.5%, respectively. The biochar significantly increased the pH and decreased the mild acid-soluble Pb and Cu concentrations in the mine tailings. Specifically, SB immobilized Pb and Cu better than MB and HB did, although it did not immobilize As, Zn or Cd. Meanwhile, more attention should be paid to the potential As release as the biochar application rate increases. In conclusion, Cassia alata L. coupled with 3% of SB could be an effective measure for restoring multi-metal mine tailings. This study herein provided a promising ecological restoration technique for future practice of heavy metal stabilization in mine tailings., Competing Interests: The authors declare no conflict of interest.

To assess the influence of soil washing with a chelator on the chemical immobilization of heavy metals, batch experiments were performed on the fine fraction of a contaminated soil under various operating conditions. Results show that pre-washing with EDTA facilitated the chemical immobilization of Cu and Cr, while an opposite effect for Pb and Zn was observed, in particular when Ca(OH)(2) was added as the immobilizing agent. Metal fraction analyses of the soils indicate that soil washing can reduce the metal mobility by removing the labile fractions, while it may also destabilize some strongly bound fractions, reversely increasing the mobility and thus compromising the subsequent immobilization performance to some extents. To secure an effective combination of soil washing and chemical immobilization for the remediation of heavy metal-contaminated sites, a comprehensive study on metal fraction distribution in the soil is needed., (Copyright 2010. Published by Elsevier B.V.)

The current acid deposition critical loads in Guangdong, China were calculated using the PROFILE model with a 3 km x 3 km resolution. Calculations were carried out for critical loads of potential acidity, actual acidity, sulfur and nitrogen, with values in extents of 0-3.5, 0-14.0, 0-26.0 and 0-3.5 kmol/(hm2 x year), respectively. These values were comparable to previously reported results and reflected the influences of vegetation and soil characteristics on the soil acid buffering capacity. Simulations of SO2 emission and sulfur deposition in this study showed that sulfur deposition core areas mirrored SO2 emission centers. The prediction of sulfur deposition after 20% and 40% reduction of SO2 emission suggested that the reduction of area sources contributed greatly to the decrease of sulfur deposition. Thus, abatement of area source emissions could be the primary way to mitigate sulfur deposition in Guangdong to meet both the provincial and national regulations of air pollution control.