Search

The Hg released from coal mining activities can endanger soil ecosystems and pose a risk to human health. Understanding the accumulation characteristics of mercury (Hg) in coal mining soil is important for effectively controlling Hg emissions and developing measures for the prevention and control of Hg contamination. To identify the potential sources of Hg in soils, the Hg concentration and isotopic composition characteristics of raw coal and different topsoil types from the areas surrounding a coal mine were determined in this study. The results showed that Hg in coal mainly exists mainly in the form of inorganic Hg, and Hg has experienced Hg2+ photoreduction prior to incorporating into coal. In addition, the composition of Hg isotopes differed significantly among different topsoil types, and the δ202Hg value of the farmland soil exhibited large negative excursions compared to the coal mining soil. The ternary mixed model further revealed the presence of substantial differences in potential Hg sources among the two regions, with the coal mining soil being greatly disturbed by anthropogenic activity, and the relative contributions of Hg from raw coal, coal gangue, and background soil to coal mining soil being 33.42%, 34.4%, and 32.19%, respectively. However, Hg from raw coal, coal gangue and background soil contributed 17.04%, 21.46%, and 61.51% of the Hg in the farmland soil, indicating that the accumulation of Hg in farmland soil was derived primarily from the background soil. Our study demonstrated that secondary pollution in soil caused by immense accumulation of solid waste (gangue) by mining activities offers a significant challenge to ecological security. These findings provide new insights into controlling soil Hg in mining areas and further highlight the urgency of strict protective measures for contaminated sites. [Display omitted] • Mercury release caused by coal mining activities endangers soil ecosystems • Differences in Hg isotopes in distinct types of soil • The accumulation of Hg in coal mining soil is mainly affected by anthropogenic perturbations • The contribution of coal gangue to soil Hg cannot be ignored [ABSTRACT FROM AUTHOR]

The increasing salinization of groundwater renders it challenging to maintain the water quality. Moreover, knowledge regarding the characteristics and mechanism of groundwater salinization in mining areas remains limited. This study represents the first attempt of combining the hydrochemical, isotope (δD, δ18O, δ37Cl, and 87Sr/86Sr) and multivariate statistical analysis methods to explore the origin, control, and influence of fluoride enrichment in mining cities. The TDS content of groundwater ranged from 275.9 mg/L to 2452.0 mg/L, and 54% of the groundwater samples were classified as class IV water according to China's groundwater quality standards (GB/T 14848–2017), indicating a decline in the water quality of the study area. The results of the groundwater ion ratio and isotope discrimination analysis showed that dissolution and evaporation involving water-rock interactions and halite were the main driving processes for groundwater salinization in the study area. In addition to the hydrogeological and climatic conditions, mine drainage inputs exacerbated the increasing salinity of the groundwater in local areas. The mineral dissolution, cation exchange, and evaporation promoted the F− enrichment, while excessive evaporation and salinity inhibited the F− enrichment. Gangue accumulation and infiltration likely led to considerable F− enrichment in individual groundwater regions. Extensive changes in the groundwater salinity indicated differences in the geochemical processes that controlled the groundwater salinization. Given the particularity of the study area, the enrichment of salinization and fluoride triggered by mining activities cannot be ignored. [Display omitted] • Use isotope and ionic contents to identify the salinity of groundwater. • Various geochemical processes control groundwater salinization. • The input of mine drainage intensifies the salinization of groundwater. • Intense evaporation and salinity could restrict the enrichment of fluoride. • The salinization of groundwater in mining area needs to be optimized. [ABSTRACT FROM AUTHOR]

The external nitrogen load input caused by human activities exacerbates the eutrophication process of aquatic ecosystems in mining areas, causing water quality problems. However, knowledge of the sources and environmental behavior of nitrate in the surface water of mining areas is still very limited. This study investigated the nitrate content and spatiotemporal variation characteristics of surface water in the Linhuan mining area, identified the sources and transformation processes of nitrate using isotopes and hydrochemistry, and evaluated the contribution rates of different potential nitrate sources based on a Bayesian mixing model. The nitrogen pollution in the surface water in the mining area seriously exceeded class Ⅴ of the Environmental Quality Standard of Surface Water of China (GB3838-2002). The NO 3 − content ranged from 0.87 to 3.41 mg/L, showing obvious seasonal and spatial differences. Isotope and NO 3 −/Cl− analysis indicated that nitrate in the subsidence area water (SAW) was mainly derived from chemical fertilizer (NF) and soil organic nitrogen (NS), while nitrate in the mainstream of the Huihe River water (HRW) was mainly derived from manure/sewage (MS). The nitrate in the tributary of the Baohe River water (BRW) was mainly derived from soil NS, and nitrification was a nitrogen conversion pathway in the soil. The results of the Bayesian mixing model showed that the main sources of nitrate in the BRW, HRW and SAW were NF (34.5%), MS (68.8%) and NF (40.8%) in the wet season, and NS (33.4%), MS (70.9%) and NF (58.1%) in the dry season, respectively. The results of this study provide a new integrated method for the identification of nitrate pollution sources in mining areas, and this method can be used to improve the biogeochemical information of nitrogen in the aquatic ecosystems of mining areas and help formulate relevant measures to reduce water nitrogen pollution. Image 1 • The isotope and Bayesian mixing model technology was first used in mining area. • Use δ15N and δ18O to identify the spatio-temporal changes of nitrate sources. • Manure/sewage were the main nitrate sources of river. • Soil organic N and chemical fertilizer were the main nitrate sources of subsidence area. • Mine drainage is another additional important source of nitrate. [ABSTRACT FROM AUTHOR]

• Low and medium deacetylation degree have little effect on the fermentability of KGM. • High deacetylation degree showed lower fermentability than that of KGM. • The lower fermentability be related to the change of physicochemical properties. • The deacetylation degree should be considered in the production of konjac foods. Deacetylation was a phenomenon widely existed during konjac glucomannan (KGM) processing, which highly effected its functional properties. Herein, influence of deacetylation degree (DD) of KGM on microbial metabolites and gut microbiota was studied in vitro. The fermentability of KGM was relatively stable under the low (Da1) and medium (Da2) DD. But high DD (Da3) shown lower fermentability than that in KGM, which was characterized with the decreasing reducing sugar content, endo -β-mannanase activity and total short-chain fatty acids (SCFAs). Meanwhile, compared with KGM, Da3 shown lower relative abundance of Actinobacteria and Bacteroide, and higher amounts of Fusobacteria and Proteobacteria to some extent. The negative effect on fermentability caused by deacetylation might be related to the reduction of solubility and viscosity, and increase the degree of molecular ordering. Our findings suggested that control of DD should be taken into consideration in the process of making konjac gel products. [ABSTRACT FROM AUTHOR]

Context Sulfur mustard (SM), a bifunctional alkylating agent, can react with a variety of biochemical molecules (DNA, RNA, proteins and other cell components) to cause a series of serious health issues or even death. Although a plethora of research has been done, the pathogenesis of SM poisoning has yet to be fully understood due to its high complexity. As a consequence, a specific antidote has not yet been developed and the treatment of SM poisoning remains a medical challenge. In recent years, various biological products and cell transplantation in the treatment of SM poisoning offered a significant clinical treatment progress. By highlighting these and other research studies, we hereby summarize the progress in this field in an effort to provide useful information on the clinical treatment of SM poisoning. Objective This review summarizes the major advances of SM poisoning therapy by means of biological products (peptide and protein drugs, polysaccharides drugs, nucleic acid drugs, etc.), and cell transplantation (e.g., bone marrow, limbal stem cells, mesenchymal stem cells), as well as other relevant biotherapeutic approaches. Method We searched the database PubMed for published domestic and international articles using web based resources for information on histological, immunochemical, ultrastructural, and treatment features of SM-induced manifestations in both animal models and human tissues. To this end, we applied keywords containing mustard gas, chemical warfare, SM, eye, lung and skin. Results and conclusion Our review provides a comprehensive understanding of the advances of available biotherapies in SM poisoning, and its potential for the treatment of SM-induced injuries. Potentially, our review will provide new insights for future research studies in this field. [ABSTRACT FROM AUTHOR]