Environmental Geochemistry and Health最新文献

The aggregation of Cadmium (Cd) in rice grains is a significant threat to human healthy. The complexity of the soil-rice system, with its numerous influencing parameters, highlights the need to identify the crucial factors responsible for Cd aggregation. This study uses machine learning (ML) modeling to predict Cd aggregation in rice grains and identify the influencing factors. Data from 474 data points from 77 published works were analyzed, and eight ML models were established using different algorithms. The input variables were total soil Cd concentration (TS Cd) and extractable Cd concentration (Ex-Cd), while rice Cd concentration (Cd_rice) was the output variable. Among the models, the Extremely Randomized Trees (ERT) model performed the best (TS Cd: R² = 0.825; Ex-Cd: R² = 0.792), followed by Random Forest (TS Cd: R² = 0.721; Ex-Cd: R² = 0.719). The ERT feature importance ranking analysis revealed that the essential factors responsible for Cd aggregation are cation exchange capacity (CEC), TS Cd, Water Management Model (WMM), and pH for total soil Cd as input variables. For extractable Cd as an input variable, the vital factors are CEC, Ex-Cd, pH, and WMM. The study highlights the importance of the Water Management Model and its impact on Cd concentration in rice grains, which has been overlooked in previous research.Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary.The authors and their respective affiliations are correct.Author details: Kindly check and confirm whether the corresponding author is correctly identified.It is correct.

Endogenous phosphorus release from sediments is a major cause of eutrophication in water bodies. To investigate the endogenous phosphorus morphological features and migration patterns in lakes under the influence of agricultural irrigation areas, we analyzed the changes of polymorphic phosphorus content in lake sediments under irrigation withdrawal conditions based on field sampling tests and sediment phosphorus release dynamics simulation experiments and used the diffusive flux method to determine the flux of phosphorus release from the sediment-water interface (SWI). The results showed that: (1) Data from encrypted sampling during the receding period revealed total phosphorus (TP) of lake water decreased from 0.11 mg/L to 0.05 mg/L, and TP of sediment increased from 723.53 mg/kg to 955.89 mg/kg. (2) The order of polymorphic phosphorus content of sediments at the lake inlet before the irrigation period was Fe-Al bound phosphorus (NaOH-nrP) > insoluble phosphorus > Fe-Al oxide bound phosphorus (NaOH-rP) > Calcium bound phosphorus (Ca-P) > Fe-Mn chelated phosphorus (BD-P) > active phosphorus. Interconversion between sedimentary polymorphic phosphorus is more drastic after the irrigation period. (3) The phosphorus forms extracted from sediments were ranked as insoluble phosphorus > NaOH-nrP > NaOH-rP > active phosphorus > Ca-P > BD-P. Insoluble phosphorus is the predominant form of phosphorus in sediments. (4) The TP exchange fluxes between the SWI by the diffusive flux method were 0.30 mg/(m2·h) and -0.33 mg/(m2·h) respectively. Receding water conditions promote sediment adsorption of TP from overlying water. The research findings establish a theoretical foundation for endogenous phosphorus from lake sediments in agricultural irrigation areas.

A pot experiment was conducted to investigate the differences in heavy metal accumulation in different varieties of leafy vegetables (five leafy vegetables four or five varieties of each) and their potential risk. The results revealed that the concentrations of Cd in all the vegetables exceeded the limit for China (0.2 mg/kg) and that the As and Pb concentrations were within the limit. The bioaccumulation of Pb, Cd, and As in spinach (0.01, 1.08, and 0.02) and rape seedlings (0.004, 0.43, and 0.03) were the highest and lowest, respectively. Health risk assessments indicate that the hazard index (HI) ranged from 0.66 to 3.37 and 2.86 to 14.64 for adults and children, respectively, and the total carcinogenic risk (TCR) ranged from 2.13E-03 to 1.86E-02 and 9.27E-03 to 8.07E-02. Probabilistic health risk assessment revealed that the HI was 3.06 and 4.75, and the TCR was 2.5E-03 and 8.88E-04 for adults and children, respectively. More importantly, heavy metal accumulation significantly differed among varieties of leafy vegetables, especially spinach. The BF of Pb, Cd, and As in spinach ranged from 0.003 to 0.01, 0.77 to 1.39, and 0.01 to 0.02, respectively. Geodetector analysis revealed that oxalic acid, available As, and organic matter are the key factors that affect Pb, Cd, and As accumulation, respectively, in these vegetables. These results suggest that the planting of suitable types and varieties of vegetables can reduce the potential health risk to a certain extent and that more effective measures should be implemented to ensure the safety of local residents in areas contaminated with heavy metals.

To effectively prevent and control pollution from heavy metals (HMs) in urban soils, it is essential to thoroughly understand the contamination status of contaminated sites. In this study, the contamination status and sources of six HMs (As, Cu, Cr, Ni, Pb, Cd) in the soil of a decommissioned chemical plant in southern China were comprehensively analyzed. The results indicated that the average concentration of HMs followed the sequence: Cr > Pb > Cu > Ni > As > Cd. Heavy metal accumulation in the upper soil layer was predominantly observed in industrial zones and low-lying areas, with notable variations in concentration along the vertical profile. Certain sections of the site exhibited severe HM contamination, particularly with Cu levels exceeding the background value by 46.77 times. Cd presented significant ecological risks in specific areas, with an average Ecological Index of 96.09. Carcinogenic and non-carcinogenic risks were identified at three and six sampling points, respectively, with sampling point S103 demonstrating both types of risks. The causes of HM contamination were primarily attributed to anthropogenic activities. Horizontal dispersion was mainly influenced by production operations and topographical features, while vertical distribution was predominantly affected by the permeability characteristics of the strata. The causality analysis incorporating production activities and topographical factors provides novel perspectives for understanding sources of contamination at contaminated sites. The study outcomes can offer guidance for the assessment and surveying of urban industrial pollution sites.

Constructed wetlands are used to remove diclofenac and naproxen from wastewater. However, the role of plants and their root-associated bacteria in removing these pharmaceuticals is still unknown. In this work, bacteria were isolated from the roots of Typha latifolia cultivated in a constructed wetland to treat a diclofenac and naproxen mix. 16S rDNA sequencing indicated that bacterial isolates belong to the Pseudomonas, Serratia, and Rahnella genera. All bacterial isolates showed tolerance to high concentrations of diclofenac and naproxen and had differential laccase activity, phosphate-solubilizing activity, and indole acetic acid production.Bacteria were grouped into three consortia A (0-30 cm), B (50-80 cm), and C (100-130 cm), according to the site from which they were isolated in the wetland. Plant-bacteria interaction assays were conducted to determine the removal capacity of diclofenac and naproxen mix by the bacterial consortia or their interaction with T. latifolia. The results showed that all bacterial consortia removed over 50% of diclofenac and naproxen, while in their interaction with T. latifolia the removal capacity increased to over 70%. Consortium B was the most efficient in removing diclofenac and naproxen, with removal rates of 63.85 ± 0.45% and 74.93 ± 0.75%, respectively. Meanwhile, in the interaction of consortium B with T. latifolia, the removal of diclofenac and naproxen increased to 82.27 ± 0.30% and 88.12 ± 1.23%, respectively. Overall, the results indicated that T. latifolia and its root-associated bacteria removed the diclofenac and naproxen mix in the constructed wetland, contributing to understanding the role of the plant and bacteria in removing emerging contaminants. Therefore, the interaction of T. latifolia and its root-associated bacteria could potentially be used in strategies to remove emerging contaminants from wastewater.

Long-term coal mining activities have significantly disturbed the groundwater system, resulting in aquifer water characterized by high levels of Na⁺, SO₄^2-, and total dissolved solid (TDS), posing environmental health risks. To investigate the disturbance effects of coal mining activities on the groundwater system and ascertain the goaf water (OGW) environmental impacts, this study focuses on the surface water (SW), major aquifers, and OGW of Jiaozhuang Coal Mine. Through ion analysis and self-organizing map (SOM) clustering, the study analyzes the hydrochemical characteristics of the aquifer water, summarizes the accumulation patterns of OGW, and evaluates water quality of irrigation and drinking using sodium adsorption ratio (SAR), sodium percentage (SSP), and comprehensive pollution index (F). The results show that the hydrochemical characteristics of the groundwater system are influenced by a combination of cation exchange, dissolution, and mixing processes, with deep aquifers exhibiting high Na⁺ and SO₄^2- levels. The OGW mainly originates from the coal roof sandstone aquifers water (RSW) and 3rd limestone aquifer water (3LW). Additionally, the groundwater shows high alkalinity and salinity hazards, with irrigation water quality assessments falling into general and unsuitable water quality area. Moreover, the groundwater quality is below Class III standards, with the worst being Class V, rendering it unsuitable as a drinking water source. Untreated discharge of OGW to the surface can easily threaten human drinking water health. The study results are helpful in identifying and controlling groundwater pollution caused by coal mining, ensuring the safety and sustainable utilization of water resources in mining areas and surrounding regions.

Plastics have been pervasive in society for decades, causing extensive environmental contamination. The co-occurrence of microplastics (MPs) and phthalate esters (PAEs) in the environment has significant implications for the global population. This review focuses on the simultaneous presence of MPs and PAEs, exploring co-pollution, leaching, adsorption, correlation, and co-toxicity. Both MPs and PAEs are found in various environmental compartments, including water, sediments, aquatic organisms, pig feed, masks, gloves, and liquid waste from garbage infiltration. Factors such as time, temperature, UV light exposure, and the type of MPs can influence the leaching and adsorption of PAEs onto MPs. The correlation between MPs and PAEs allows for the use of PAEs as indicators for the presence of MPs. However, current constraints, like limited data availability and regional coverage, impede the feasibility of comprehensive tracking. Additionally, the combined effects of MPs and PAEs demonstrate synergistic toxicity, leading to adverse health effects such as reproductive toxicity, neurotoxicity, hepatotoxicity, nephrotoxicity, and other toxicities, primarily mediated by oxidative stress processes. Consequently, the findings provide valuable insights for future researchers and regulatory bodies, enabling the development of more effective strategies to address the simultaneous presence of microplastics and PAEs and mitigate their harmful impacts on human health.

Human survival hinges on access to water, which provides vital necessities. It is crucial to secure reliable, affordable, and uncontaminated water to maintain health and sustain life. For the potential impact of radioactive water pollution on human well-being, a scintillation-based smart RnDuo detector was employed in the Pattan region of North Kashmir Baramulla to quantify radon levels in diverse underground water. The dose contribution to various organs through inhalation and ingestion pathways has been analyzed. The study assesses the levels of radon in water, which varied from 19.88 to 74.37 Bq/L with an average of 37.65 Bq/L. All of the values were higher than the United States Environmental Protection Agency(USEPA) suggested guideline of 11 Bq/L but lower than the 100 Bq/L prescribed by the World Health Organization (WHO). The age group-wise inhalation and ingestion doses are higher than the 100 μSv/y recommended by WHO but within the prescribed range of 3-10 mSv/y as suggested by the International Commission on Radiological Protection (ICRP). Doses to various organs (lungs and stomach) are also calculated in the present study. The results of the present investigation will help to enhance the quality of the water and guide future epidemiological studies.

This research is on lactating mothers in the city of Chah Bahar in Iran. This descriptive-analytical and questionnaire study selected a random sample of 80 mothers to examine mercury levels in their hair, milk, and saliva. The average concentration of mercury in milk, hair and saliva of mothers was 1.23 ± 0.48 µg/l, 1.81 ± 0.55 µg/g and 1.10 ± 0.63 µg/l, respectively. There was a significant correlation between mercury levels in mothers saliva and hair. Still, only a weak correlation was found between mercury levels in milk and hair, and milk and saliva, possibly associated with the high lipid content in milk. The number of children and length of the mother's pregnancy were related to the amount of mercury in the mother's milk. The number of teeth filled with amalgam, consumption of fish and marine products, consumption of fruit, and infant's weight at birth were also associated with the amount of mercury in breast milk. Chewing gum, fish consumption, infant's birth weight, weight, and length of pregnancy were among the factors associated with the amount of mercury in mothers' saliva. The mercury concentration in milk exceeded the WHO (1.4-1.7 µg/g) normal level in 8.5% mothers, and hair mercury was found in 12.5% mothers. It should be kept in mind that any amount of mercury can be harmful.

Microplastics (MPs) and pesticides are two pollutants of concern in agricultural soils. 3,5-dichloroaniline (3,5-DCA), a highly toxic metabolite of dicarboximide fungicides, commonly co-exists with MPs and poses a risk to the environment and food safety. Batch adsorption and soil incubation experiments were employed to investigate the effects of polyethylene (PE) and polylactic acid (PLA) MPs on the environmental behavior of 3,5-DCA in soil. Chive (Allium ascalonicum) was used as the experimental plant, a pot experiment was conducted to examine the effects of individual or combined exposure to MPs and 3,5-DCA on plant 3,5-DCA bioaccumulation, growth characteristics, and phytotoxicity. The results showed that PE- and PLA-MPs increased the adsorption capacity of soil to 3,5-DCA and prolonged the degradation half-life of 3,5-DCA by 6.24 and 16.07 d, respectively. Two MPs partially alleviated the negative effects of 3,5-DCA on the root length and fresh weight of chives, while PE-MPs had a positive and dose-dependent impact on the contents of photosynthetic pigment in chive leaves. Co-exposure to 3,5-DCA and MPs increased residues of 3,5-DCA in soil and chive roots but had no significant effect on 3,5-DCA residues in chive stems or leaves. Moreover, 3,5-DCA residues in PLA-MP soil were consistently higher than those in PE-MP soil. Conclusively, MPs altered the 3,5-DCA adsorption and degradation behavior in soil, as well as its bioaccumulation in chives. Co-exposure to MPs and 3,5-DCA had dose-dependent and MP-specific effects on chive plant development and phytotoxicity.