Pollution Characteristics Research Articles

Causal analysis of PM2.5 propagation characteristics during the winters of 2015 to 2023 in Hubei Province, China

To discuss the causes and characteristics of occasional severe winter pollution in Wuhan, Hubei Province, China amidst the continuous improvement of the atmospheric environment, this research utilizes air quality monitoring data from various cities in Hubei Province during the winters of 2015–2023, analyzing changes in air quality in Hubei Province using PM2.5 concentration values as an indicator. We employ the Convergent Cross Mapping (CCM) method, using Wuhan and other cities in Hubei Province as examples, to reveal the causal impact of other cities within Hubei Province on winter PM2.5 pollution in Wuhan from a causality perspective. The results indicate an improvement in air quality during the winters of 2015–2023 in Hubei Province. The PM2.5 concentration in Wuhan during winter is influenced by four other cities within Hubei Province, indicating a clear causal relationship between the PM2.5 concentrations in these two regions. The Convergent Cross Mapping (CCM) method accurately identifies both the strength and direction of the causal relationship between two variables, providing invaluable guidance for subsequent research in atmospheric environmental governance.

Adsorption Characteristics of Organic Pollutants on Montmorillonites Modified by Quaternary Ammonium Surfactants with Organic Counterions

Adsorption Characteristics of Organic Pollutants on Montmorillonites Modified by Quaternary Ammonium Surfactants with Organic Counterions

Research on Centroid Tracking Algorithm for Oil Stain Defects on the Surface of Silk Cake

As the basic material for the production of specific fabrics, the yarn quality of chemical fiber cake directly affects the fabric quality. The problem of oil on the surface of silk cake will lead to uneven yarn coloring, which will affect the quality of fabric. In order to solve this problem, a method of detecting oil stain defect of textile silk cake based on graph centroid tracking algorithm is proposed in this paper. In this method, the silk cake image is obtained, downsampled and gray-scale processed, and then Gaussian filtering and binarization are applied to enhance the image clarity. Next, the edge outline and its minimum external rectangle are drawn, and a mask image is constructed to highlight the oil area. By setting the oil pollution pixel range and processing the image after mask, log operator and expansion processing are used to enhance the oil pollution characteristics. Finally, the contours are extracted and the centroid coordinates are calculated. By comparing with the vertex coordinates of the minimum external rectangle, the oil pollution is automatically located. The method has high detection accuracy and short time, and can effectively solve the problem of oil stain defect detection of textile silk cake.

Current Used Pesticides in Air and Soil in Eastern China: Occurrence, Spatial-Seasonal Distribution, and Air-Soil Exchange.

Current used pesticides (CUPs) are extensively used as alternatives for traditional pesticides in the world. In order to investigate the pollution characteristics of CUPs in a large-scale multimedium environment, a comprehensive and comparative study was conducted on occurrence, spatial-seasonal distribution, and air-soil exchange of CUPs across 30° latitude in Eastern China. A total of 72 target CUPs were detected, and 43 CUPs had a detection frequency over 30% in both air and soil samples. Herbicides, fungicides, and organophosphorus insecticides predominantly exhibited volatilization from soil to air, while pyrethroids exhibited deposition from air to soil. In the high-latitude Northeastern China, the air-soil exchange net flux of CUPs was the lowest due to the lower temperature, especially in winter. Along with decreasing latitude and increasing temperature, the air-soil exchange flux increased, which was significantly influenced by cultivation practices and the usage frequency of CUPs. Therefore, the grasshopper effect driven by temperature difference caused further migration and deposition of CUPs toward higher latitude regions. Moreover, the emission fluxes of CUPs to soil exhibited significant variations closely linked to local climatic conditions and types of crops. In summary, this study obtained valuable baseline information for the pollution characteristics and air-soil exchange of CUPs on a large scale, which also provided a better understanding of the environmental fate of CUPs from the migration perspective.

Pollution characteristics and potential sources of Peroxyacetyl Nitrate in a petrochemical industrialized City, Northwest China.

Pollution characteristics and potential sources of Peroxyacetyl Nitrate in a petrochemical industrialized City, Northwest China.

Exploring indoor PM2.5 pollution characteristics in Xi'an city and its health implications using interpretable machine learning

Exploring indoor PM2.5 pollution characteristics in Xi'an city and its health implications using interpretable machine learning

Pollution characteristics, spatial variation, and ecological risks of phthalate esters in seawater and sediment from nine estuaries and their adjacent areas of Hainan Island, China.

Pollution characteristics, spatial variation, and ecological risks of phthalate esters in seawater and sediment from nine estuaries and their adjacent areas of Hainan Island, China.

Behavior of carbon source type on the construction of aerobic granular sludge system and its removal of quinoline: A tortoise and hare race between starch and phenol.

Behavior of carbon source type on the construction of aerobic granular sludge system and its removal of quinoline: A tortoise and hare race between starch and phenol.

Microplastics in China's surface water systems: Distribution, driving forces and ecological risk.

Microplastics in China's surface water systems: Distribution, driving forces and ecological risk.

Ensemble learning-assisted quantitative identifying influencing factors of cadmium and arsenic concentration in rice grain based multiplexed data.

Ensemble learning-assisted quantitative identifying influencing factors of cadmium and arsenic concentration in rice grain based multiplexed data.

Composting treatment increases the risk of microplastics pollution in process and compost products.

Composting treatment increases the risk of microplastics pollution in process and compost products.

Emission Characteristics of Hydrogen-Enriched Gasoline Under Dynamic Driving Conditions

This paper investigates the emission characteristics of hydrogen-enriched gasoline (95G5H2) under dynamic driving situations in order to fulfill the growing need for cleaner and more efficient automobile fuels. This study aimed to investigate the impact of hydrogen addition on pollutant-specific emissions, including CO, CO2, HC, and NOx, using a Nissan Qashqai that ran on both pure gasoline (100G) and 95G5H2. Emission statistics were obtained by computer simulations of the Worldwide Harmonized Light Vehicles Test Cycle (WLTC) applied using AVL CRUISE software. The paper presents a method of comparing the characteristics of pollutants emitted by the combustion engine and comparing the pollutants emitted when powered by regular fuel and fuel with hydrogen. The tests were performed in real conditions, and the presented method shows the amount of pollutants emitted when the vehicle is directly in motion, which allows for effective comparison of the amount of pollutants emitted for different fuels. 95G5H2 sharply reduces CO-, CO2-, and HC-specific emissions by 22.19%, 14.55%, and 35.46%, respectively, when compared to 100G. However, NOx-specific emissions increased by 20.17%, suggesting a compromise between higher combustion efficiency and higher burning temperatures. The study shows that 95G5H2 fuel performs better in urban driving cycles, including plenty of acceleration and deceleration, which usually results in incomplete combustion. Although additional refinement is needed to cut NOx-specific emissions, the results demonstrate that hydrogen-enriched fuels have considerable potential to lower vehicle-specific emissions. The significant conclusions of the study on the advantages of hydrogen-enriched fuels, both practically and environmentally, will help in the future development of environmentally friendly transportation solutions.

Content, Distribution, and Risk Assessment of Heavy Metals in Sandy Soils of the Ancient Yellow River Course

ABSTRACT Heavy metal pollution characteristics in soils of the ancient Yellow River course are related to the ecological security of the whole Yellow River basin. In this study, the soils were collected from two functional areas (artificial forest and farmland) of the ancient Yellow River course in Yuanyang, Henan. The sand percentage was greater than 58%, and the soil was weakly alkaline with low organic matter content in the study area. The heavy metal contents in the soils were in the following order: Cr > Zn > Cu > Pb > Cd, and heavy metals might mainly originate from geological activities and pesticide residues. The metals were at a warning pollution level, and the monomial potential ecological risk factor and the risk quotient showed an ecological risk for Cd and Cr. The non-carcinogenic risk and carcinogenic risk of soil heavy metals were within the safety limits, and the non-carcinogenic risk for children was greater than that for adults. The carcinogenic risk in children and adults was within the acceptable range, but the risk was non-negligible. Taken together, these results can benefit the ecological protection and high-quality development of the Yellow River Basin and facilitate the adoption of safe regional agricultural production practices.

Study on the Pollution Characteristics of Characteristic Elements in Atmospheric PM2.5 in a Special Region and Their Deposition Patterns in the Upper Respiratory System

The impact of PM2.5 on the environment and human health has garnered significant attention. While research on PM2.5 composition is increasing, fewer studies have focused on how dusty conditions in a special region affect the PM2.5 composition. This region’s unique environmental conditions, characterized by frequent dust events, complicate air quality management. The study investigates the seasonal distribution of inorganic elements in the PM2.5 under both dusty and non-dusty conditions through systematic sampling. Selective screening methods identified key pollutant elements, and a respiratory system model was developed to examine their diffusion and deposition patterns in the upper respiratory tract. Key findings reveal that inorganic element concentrations in the PM2.5 follow consistent seasonal trends, with significantly higher levels during dust events compared to non-dusty periods. Crustal elements are dominated in the PM2.5, but non-metallic elements (Cl, S) and metallic/quasi-metallic elements (Mn, Cd, Cr, As, Hg) are also prevalent, likely influenced by anthropogenic activities and industrial emissions. By PCA with human health assessments, six characteristic pollutants were identified: As, Co, Cd, Cr, V, and Mn. Simulations using COMSOL Multiphysics 6.2 software demonstrated distinct behaviors: As tends to concentrate in the posterior regions of the respiratory tract, while Co and Cd exhibit relatively uniform distributions, primarily affecting areas where airflow slows upstream. Cr, V, and Mn show dispersed and uniform patterns. Notably, even during dusty conditions, the concentration of the six pollutants remains relatively low in the different parts of the upper respiratory tract, suggesting minimal immediate health impacts. Our study provides valuable insights into the behavior of inorganic elements in the PM2.5 and their potential health implications, highlighting the need for further research on the effects of dusty conditions on air quality and public health.

Source-oriented health risk of heavy metals in sediments: A case study of an industrial city in China.

Source-oriented health risk of heavy metals in sediments: A case study of an industrial city in China.

Insights Into Air Pollution Dynamics and Quality: A Comprehensive Analysis Of Scholarly Research In Türkiye

Air pollution affects human health, the environment, and the economy worldwide. This comprehensive analysis elucidates the intricate characteristics of air pollution and its quality by amalgamating the latest study outcomes derived from papers published on the DergiPark platform in Türkiye throughout the period spanning from 2022 to 2023. The papers in our study are classified according to their research themes. The main findings suggest that weather, urbanization, industry, and wildfires affect air pollution and quality. Additionally, the COVID-19 pandemic has affected air quality dynamics, requiring further study. Scientists have used various methods to forecast, evaluate, and simulate, but challenges remain that require new approaches. Investigating the causal pathways linking air pollution to climate change, urban development, and transportation will help us better understand the problem. Empirical study into the effects of air pollution and quality on human health is essential for making informed policy decisions, especially for vulnerable groups. Evaluating the efficacy of current regulations and establishing new approaches can help guide effective air quality. This paper is a comprehensive synthesis of scholarly studies pertaining to air quality and pollution, providing a comprehensive overview of the extensive ramifications associated with this subject matter.

Characteristics of dust pollution and its influencing factors during cold period of open-pit coal mines in northern China

Characteristics of dust pollution and its influencing factors during cold period of open-pit coal mines in northern China

A Nationwide Investigation of Substituted p-Phenylenediamines (PPDs) and PPD-Quinones in the Riverine Waters of China.

N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-Q) has been identified as the cause of the "urban runoff mortality syndrome." Thus, the ecological risks of substituted p-phenylenediamines (PPDs) and their quinone derivatives (PPD-Qs) in water have gained global attention. However, large-scale observation of their pollution characteristics in surface water is still lacking. Herein, a nationwide investigation revealed the pervasive occurrence of PPDs and PPD-Qs in riverine waters across China, with the mean concentration of ∑5PPD-Qs being 4.9 times higher than their parent ∑5PPDs. Notably, the 6PPD-Q concentrations at eight sampling sites exceeded the median lethal concentration for coho salmon. National annual riverine fluxes were estimated at 113.1 and 276.2 tonnes/year for PPDs and PPD-Qs, respectively, with the Yangtze River contributing more than one-third of the total fluxes. The transformation of PPDs to PPD-Qs was dependent on atmospheric hydroxylation rates and the half-lives of PPDs. A combined multimedia exposure assessment revealed that water exposure accounted for 82.5% of human exposure to PPDs and PPD-Qs, surpassing the contributions from dust and air exposure. This study provides a comprehensive spatial picture of PPDs and PPD-Qs in China. The national atlas highlights their potential ecological risks and implies that targeted actions should be taken to mitigate potential exposure to PPDs and PPD-Qs.

Pollution characteristics, source analysis, and health risk assessment of polycyclic aromatic hydrocarbons in atmospheric PM2.5: a case study in Xi’an, China

ABSTRACT Air samples were collected at the Lianhu (urban) and Yanta (semi-urban) regions between January 2020 and December 2023 to determine the concentrations of polycyclic aromatic hydrocarbons (PAHs) in Xi’an, which is an important tourist city in China. The concentration of PAHs was ascertained using liquid chromatography. The concentration of Σ16PAHs in Xi’an was 0.13–105.02 ng/m3, while the concentration of Σ16PAHs for the sampling regions at Lianhu and Yanta were 0.13–105.02 ng/m3 and 0.34–82.64 ng/m3, respectively. PAHs with 4–5 rings were the predominant PAHs pollutants in Xi’an, mainly from coal combustion and automobile exhaust. Risks through inhalation to three groups, adult males, adult females, and children, were estimated. The incremental lifetime cancer risk (ILCR) value for local adults and children were less than 10−6, considered to be at a safe level. However, the ILCR is relatively close to the minimum risk threshold (10−6), and it still needs to be highly valued.

Characteristics of Water-soluble Ions in Atmospheric Particulates in Farmland in the Suburb of Nanjing

Water-soluble ions are an important component of atmospheric particles. However, there has been limited research on water-soluble inorganic ions in atmospheric particulates in agricultural areas until now. In this study, the characteristics of eight water-soluble inorganic ions （Na+, NH4+, K+, Mg2+, Ca2+, NO3-, SO42-, and Cl-） in different sizes of atmospheric particulates （>9.0, 5.8-9.0, 4.7-5.8, 3.3-4.7, 2.1-3.3, 1.1-2.1, 0.65-1.1, 0.43-0.65, and <0.43 μm） were analyzed by sampling farmland in the suburb of Nanjing from December 2020 to November 2021. The results showed that the annual mass concentrations of total suspended particulate matter （TSP）, < 9.0 μm and < 2.1 μm particulates were 54.73, 49.04, and 27.35 μg·m-3, respectively, all of which reached the national secondary standards. The mass concentration of < 2.1 μm particulates accounted for 50.0% of TSP, indicating that fine particles were the main components of atmospheric particulates in this area. The concentration of water-soluble inorganic ions in different sizes of particulates was highest in autumn, followed by those in spring/summer and winter. SO42- was the primary contributor among all seasons and particle sizes, accounting for 30.6%-66.5%. The ratio of SO42-/NO3- was much higher than 1, indicating that the contribution of fixed-source pollution played a dominant role in the study area. Moreover, SOR （SO2 gas-particle conversion rate） in different particle sizes was less than 0.1 only at individual times in winter, indicating that SO42- was mainly derived from the secondary oxidation of SO2 in the study area. Significant positive correlations （P < 0.05） between SOR and temperature were observed except for 4.7-5.8 μm particulates, indicating that the increase in temperature significantly promoted the photochemical formation process of SO42- in particles with different sizes. However, the relationship between SOR and relative humidity was significant only in fine particulates smaller than 2.1 μm （P < 0.05）, indicating that the liquid phase reaction was an important pathway for the formation of SO42- in fine particles. Principal component analysis was used to analyze the sources of water-soluble inorganic ions in particulates. Moreover, it showed that water-soluble inorganic ions in fine particulates mainly came from the secondary transformation of SO2, while those in the coarse particles mainly came from the soil dust during farmland tillage. The results of this study are of great significance for understanding the characteristics of water-soluble inorganic ion pollution in atmospheric particulate matter in agricultural areas. They provide a reference for understanding the source and formation mechanisms of atmospheric particulate matter pollution in agricultural areas near Nanjing.