Pollution evaluation and children's multimedia exposure of atmospheric arsenic deposition in the Pearl River Delta, China

Preparation of imidazolium ionic liquid functionalized paper membrane for selective extraction of caffeic acid and its structural and functional analogues from Taraxaci Herba

In the search for pharmaceutically active compounds from natural products, it is crucial and challenging to develop separation or purification methods that target not only structurally similar compounds but also those with specific pharmaceutical functions. The adsorption-based method is widely employed in this field and holds potential for this application, given the diverse range of functional monomers that can be chosen based on structural or functional selectivity. In this work, an imidazolium ionic liquid (IL) modified paper membrane was synthesized via microwave reaction. Caffeic acid (CA), with potential interactions with imidazolium IL and a representative component of phenolic acids in Taraxaci Herba, was chosen as a target compound. After optimization of synthesis and extraction parameters, the resulting extraction membrane could be used to quantitatively analyze CA at ng/ml level, and to extract CA's analogues from the sample matrix. Cheminformatics confirmed the presence of structural and functional similarity among these extracted compounds. This study offers a novel approach to preparing a readily synthesized extraction membrane capable of isolating compounds with structural and functional analogies, as well as developing a membrane solid-phase extraction-based analytical method for natural products.

Preparation of imidazole-modified paper membrane for selective extraction of gallic acid and its structural and functional analogues from Pomegranate Peel

In the search for pharmaceutically active compounds from natural products, it is crucial and challenging to develop separation methods that target not only structurally similar compounds but also a class of compounds with desired pharmaceutical functions. To achieve both structure-oriented and function-oriented selectivity, the choice of functional monomers with broad interactions or even biomimetic roles towards targeted compounds is essential. In this work, an imidazole (IM)-functionalized paper membrane was synthesized to realize selectivity. The IM was selected based on its capability to provide multiple interactions, participation in several bioprocesses, and experimental verification of adsorption performance. Using gallic acid as a representative component of Pomegranate Peel, the preparation conditions and extraction parameters were systematically investigated. The optimal membrane solid-phase extraction (MSPE) method allowed for enrichment of gallic acid from the complex matrix of Pomegranate Peel, enabling facile quantitative analysis with a limit of detection (LOD) of 0.1 ng mL-1. Furthermore, with the aid of cheminformatics, the extracted compounds were found to be similar in both their structures and pharmaceutical functions. This work offers a novel approach to preparing a readily synthesized extraction membrane capable of isolating compounds with similar structures and pharmaceutical effects, and provides an MSPE-based analytical method for natural products.

Response of trace elements in urban deposition to emissions in a northwestern river valley type city: 2010-2021

Anthropogenic activities release significant quantities of trace elements into the atmosphere, which can infiltrate ecosystems through both wet and dry deposition, resulting in ecological harm. Although the current study focuses on the emission inventory and deposition of trace elements, their complex interactions remain insufficiently explored. In this study, we employ emission inventories and deposition data for eight TEs (Cr, Mn, Ni, Cu, Zn, As, Cd, Pb) in Lanzhou City to unveil the relationship between these two aspects. Emissions in Lanzhou can be roughly divided into two periods centered around 2017. Preceding 2017, industrial production constituted the primary source of TEs emissions except for As; coal combustion was the primary contributor to Cr, Mn, and As emissions; waste incineration played a significant role in As, Zn, and Cd emissions; biomass combustion influenced Cr and Cd emissions; and transportation sources were the predominant contributors to Pb and Cu emissions. With the establishment of waste-to-energy plants and the implementation of ultra-low emission retrofits, emissions from these sources decreased substantially after 2017. Consequently, emissions from industrial production emerged as the main source of TEs. The deposition concentrations of Cr, Mn, Ni, Cu, and Pb followed a similar trend to the emissions. However, Cd and As exhibited lower emissions and a less pronounced response relationship. Moreover, Zn concentrations fluctuated within a narrow range and showed a weaker response to emissions. The consistent changes in emissions and TEs deposition concentrations signify a shift in deposition pollution in Lanzhou city from Coal-fired pollution to that driven by transportation and industrial activities. Within this transition, the industrial production process offers significant potential for emission reduction. This insight provides a crucial foundation for managing TEs pollution and implementing strategies to prevent ecological risks.

Elevated serum lead and cadmium levels associated with increased risk of dyslipidemia in children aged 6 to 9 years in Shenzhen, China

Exposure to heavy metals can influence on metabolism, but studies have not fully evaluated young children. We investigated the association between levels of serum lead (Pb), cadmium (Cd), chromium (Cr), and arsenic (As) and risk of dyslipidemia in children. A total of 4513 children aged 6 to 9 years at 19 primary schools in Shenzhen were enrolled. Overall, 663 children with dyslipidemia were matched 1:1 with control by sex and age, and levels of serum Pb, Cd, Cr, and As were detected by inductively coupled plasma-mass spectrometry. Demographic characteristics and lifestyle were covariates in the logistic regression to determine the association of heavy metal levels with risk of dyslipidemia. Serum Pb and Cd levels were significantly higher in children with dyslipidemia than controls (133.08 vs. 84.19 μg/L; 0.45 vs. 0.29 μg/L; all P < 0.05), but this association was not found in Cr and As. We found significant upward trends for the odds ratios (ORs) of dyslipidemia associated with increasing quartiles of Pb and Cd levels (highest quartile of serum Pb OR 1.86, 95% confidence interval (CI) 1.46-2.38; Cd OR 2.51, 95% CI 1.94-3.24). Elevated serum Pb and Cd levels were associated with increased risk of dyslipidemia among children.

An interpolation method incorporating the pollution diffusion characteristics for soil heavy metals - taking a coke plant as an example

The existing spatial interpolation methods in the prediction of soil heavy metal distribution are generally based on spatial auto correlation theory, rarely considering the pollution patterns. By contrast, in polluted sites, heavy metals have a strong heterogeneity even within a very small area, which is not exactly in line with auto correlation theory. This contradiction may lead to inaccuracy in spatial prediction. Atmospheric diffusion and deposition are one of the main sources of soil heavy metal pollution caused by coal-related production activities. To improve the prediction accuracy, the diffusion patterns of pollutants were considered in this paper by integrating Geodetector, Co-Kriging (COK), and partition interpolation. Geodetector was used to identify the main driving factors of soil pollution, based on which, the main driving factors were used as covariates introduced into the interpolation method (COK). Specifically, the amount of particulate matter deposition obtained by a pollutant diffusion model (AERMOD) was used as a covariate. For comparison, the distances to quenching, coke oven, and ammonium sulfate section were also used as covariates. Compared with the Ordinary Kriging method, the method COK-AERMOD established here decreased the root mean square error values of As (2.05 reduced to 1.89), Cd (0.18 reduced to 0.16), Cr (19.07 reduced to 12.97), Cu (6.92 reduced to 4.72), Hg (0.32 reduced to 0.28), Ni (16.92 reduced to 16.10), Pb (18.29 reduced to 16.62), and Zn (159.68 reduced to 153.66). This method in this paper is informative for the interpolation of soil elements in contaminated areas with known pollution source and diffusion patterns.

Heavy metals in daily meals and food ingredients in the Yangtze River Delta and their probabilistic health risk assessment

Heavy metal exposure via food consumption is inadequately investigated and deserves considerable attention. We collected hundreds of food ingredients and daily meals and assessed their probabilistic health risk using a Monte Carlo simulation based on an ingestion rate investigation. The detected concentrations of four heavy metals (Cr, Cd, Pb, and Hg) in all daily meal samples were within the limits stipulated in the National Food Safety Standard (GB 2762-2017), while that for As level was excessive in 0.3 % of daily meal samples. The same results were also observed in most food ingredient samples, and a standard-exceeding ratio of 23 % of As was observed in aquatic food or products, especially seafood, which was with the highest concentration reaching 1.24 mg/kg. Combining the detected heavy metal amounts with the ingestion rate investigation, the hazard quotients (HQs) of As, Cr, Cd, Pb, and Hg in daily meals and food ingredients were all calculated as lower than 1 (no obvious harm), while the incremental lifetime cancer risk (ILCR) of As and Cr (>1 × 10-4), indicating that the residual As posed potential health effects to human health. It was noteworthy that the proportion of aquatic foods only accounted for 6.3 % of daily meals, but they occupied 41.1 % of the heavy metal exposure, which could be attributed to the high amounts of heavy metals in aquatic foods. This study not only provided basic data of heavy metal exposure and potential health risks through daily oral dietary intake, but also illuminated the contribution of different kinds of food ingredients. Specifically, the study highlighted the contamination of aquatic foods with As, especially seafood such as shellfish and bivalves.

The research trend on arsenic pollution in freshwater: a bibliometric review

We conducted a quantitative and qualitative bibliometric analysis based on 8740 research articles from the Web of Science Core Collection published in the last 20 years (2000-2020) for a better understanding of the research progress and development trend of arsenic pollution in freshwater (FAP). The results showed a significant increase in the number of publications from 2007 to 2020, especially after 2015. Four of the top 10 productive authors are from China. Two of the top three research institutions are from China, and the publications of Chinese Academy of Sciences accounted for 5.40% of the total. China is also the center of the national cooperation network, indicating a greater influence of China in this scientific research field. The top three journals included Science of the Total Environmental, Environmental Science Technology, and Journal of Hazardous Materials. Besides arsenic, the high-frequency keywords in this field included adsorption, contamination, groundwater, removal, detection, and geochemistry. The researchers mainly focused on the groundwater environment, as well as the pollution hazards of arsenic in water bodies, remediation techniques, detection, migration, and transformation. Studies should pay more attention to the application and development of phytoremediation technology in the field of FAP in the future.