Search

Abstract: A semi-static solution culture method was used to study the effects of Ca2+ supply and interaction of Cd–Pb on the subcellular distribution of Cd and Pb in earthworm Eisenia fetida. The subcellular distribution of Cd and Pb was shown to be metal specific. About 80% of the Cd was distributed in the cytosol (fraction G), and only about 20% of total Cd was found in the tissue and cell membrane (fraction E) and the microsomes (fraction F). Nearly 50% of the Pb was rich in the tissue and cell membrane (fraction E). The supply of Ca2+ ions significantly decreased Cd concentration in the cytosol (fraction G) and the whole tissue of the E. fetida. At the subcellular level, the addition of Pb2+ ions significantly decreased the Cd percentage associated with fraction G from 83.7% to 58.4% and increased fraction E from 10.7% to 34.0%, respectively. [Copyright &y& Elsevier]

Behaviors of soil heavy metals are often affected by coexisting herbicides due to their physical and chemical interaction. Effect of glyphosate, an herbicide containing -PO_3^{2-} and -COOH groups, on cadmium adsorption in montmorillonite was studied in detail. The results showed that cadmium adsorption quantity in montmorillonite increased with increasing soil solution pH and cadmium concentration as usual, but decreased with glyphosate, which is due to the formation of a low affinity complex of Cd and glyphosate and decreasing solution pH induced by glyphosate addition. When the equilibrium solution pH was below 6.7, glyphosate has little effect on cadmium adsorption, but when the equilibrium solution pH was above 6.7, glyphosate significantly decreased cadmium adsorption quantity in montmorillonite. In addition, the adding order of Cd and glyphosate also influenced Cd adsorption quantity in montmorillonite. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM2.5) is a typical air pollutant and has adverse health effects across the world, especially in the rapidly developing China due to significant air pollution. The PM2.5 pollution varies with time and space, and is dominated by the locations owing to the differences in geographical conditions including topography and meteorology, the land use and the characteristics of urbanization and industrialization, all of which control the pollution formation by influencing the various sources and transport of PM2.5. To characterize these parameters and mechanisms, the 5-year PM2.5 pollution patterns of Jiangsu province in eastern China with high-resolution was investigated. The Kriging interpolation method of geostatistical analysis (GIS) and the HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model were conducted to study the spatial and temporal distribution of air pollution at 110 sites from national air quality monitoring network covering 13 cities. The PM2.5 pollution of the studied region was obvious, although the annual average concentration decreased from previous 72 to recent 50 μg m−3. Evident temporal variations showed high PM2.5 level in winter and low in summer. Spatially, PM2.5 level was higher in northern (inland, heavy industry) than that in eastern (costal, plain) regions. Industrial sources contributed highest to the air pollution. Backward trajectory clustering and potential source contribution factor (PSCF) analysis indicated that the typical monsoon climate played an important role in the aerosol transport. In summer, the air mass in Jiangsu was mainly affected by the updraft from near region, which accounted for about 60% of the total number of trajectories, while in winter, the long-distance transport from the northwest had a significant impact on air pollution. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM 2.5 ) is detrimental to the human respiratory system. However, the toxicity of PM 2.5 and its associated potentially harmful species, notably novel pollutants like environmentally persistent free radicals (EPFRs), remains unclear. Therefore, one-year site monitoring and ambient air PM 2.5 sampling in the Nanjing urban area was designed to investigate the relationships between chemical compositions (carbon fractions, metallic elements, and water-soluble ions) and EPFRs, and change in cytotoxicity with varying PM 2.5 components. Oxidative stress (reactive oxygen species, ROS), inflammatory injury (IL-6 and TNF-α), and membrane injury (LDH) of human lung epithelial cells (A549) induced by PM 2.5 were analyzed using in vitro cytotoxicity test. Both the composition and toxicity of PM 2.5 from different seasons were compared. The average daily exposure of urban PM 2.5 associated EPFRs load in Nanjing were 2.29 × 10 11 spin m -3 . Their exposure concentration and cytotoxic damage ability were stronger in the cold season than warm. The particle compositions of metals and carbon fractions were significantly positively correlated with EPFRs. The airborne EPFRs, organic carbon (OC), and heavy metal Cu, As, and Pb may pose principal cell damage ability, which is worthy of further study interlinking aerosol pollution and health risks., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Atmospheric haze pollution is a popular environmental issue in recent years. The aerosols reduce solar radiation reaching land surface, with consequences on the growth of crops. In order to examine the effects of low solar radiation intensity on the physiological characteristics and mineral nutrition of grain crops, the random designed field experiment of rice cultivar 'Nanjing 5055' planted under different shading degrees (CK, natural sunlight control; Y 1 and Y 2 were treatments with shading rates of 19% and 45%, respectively) were conducted. The response of chlorophyll content (SPAD), leaf area index (LAI), net photosynthetic rate of leaves, grain yields and secondary/micro element contents (Ca, Mg, Fe, Zn, Mn, Cu) in rice were measured during key growth stages (jointing, heading, and grain filling stages). Results showed that, shading treatments inhibited the synthesis of photosynthetic products and reduced the LAI during the whole growing period, but at the early stage it did not affect the chlorophyll content, which was significantly increased at the late growth stage. Compared with CK, the 1000-grain weight of rice was decreased by 14.4% and 18.4%, and seed setting rate was decreased by 4.3% and 12.9%, which resulted in rice yield reduction. With the increases of shading rates, rice yield was decreased by 58.5% and 66.4%, respectively. The nutrient concentrations, especially for the micro-elements, in brown rice and glume were increased. Shading had a negative effect on rice growth, which would eventually reduce the crop production. The higher contents of heavy metals such as Cu and Mn would be a pollution risk for human health. Therefore, the impacts of weakened solar radiation on quantity and quality of crops need comprehensive evaluation.

Environmental air pollutants pose significant threats to public health, especially the toxicity and diseases caused by the atmospheric fine particulate matters (PM 2.5 ). Since the health risks vary with both the concentrations and compositions of PM 2.5 which are determined by aerosol sources, how are their toxic effects relevant to the pollution level becomes an important issue, such as the haze episodes covering clean and polluted days. With the transition from non-pollution to pollution stage, daily PM 2.5 samples were collected from both the urban and industrial areas of Nanjing city, eastern China, covering a typical haze event in autumn-winter. Their unpropitious effects on human lung epithelial cells (A549) were compared by in vitro toxicity assays and chemical component analysis. Both air levels and cytotoxic effects of PM 2.5 varied with the transition of haze event. Although the concentration of PM 2.5 in air is of course the highest in pollution stage driven by local stable meteorological condition, unit mass of them posed higher toxicity (lower cell viability and higher IL-6) but induced lower cell oxidative (evidences of ROS and NQO1 mRNA expression) and inflammatory cytokine TNF-α responses than those particles during non-pollution stage. These patterns were explained by the metals and water-soluble components decreased with the haze development. Non-soluble particulate carbonaceous aerosol compositions might play a significant role in inducing cytotoxicity. Moreover, the regional pattern of episode pollution weakened the spatial variation within a city scale. Since the haze development intensified both the quantity and toxicity of PM 2.5 in air, the health risks of overall aerosol exposure were synthetically amplified during haze weather, so the increased air particles with higher toxic components from fuel combustion sources should be key targets of pollution control., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Atmospheric fine particulate matter (PM 2.5 ) can harm human health, but the chemical composition and toxicity of PM 2.5 pollution might vary with weather conditions. In order to investigate the impacts of snowfall weather on aerosol characteristics and toxicity by changing particle sources and components, the daily PM 2.5 samples were collected before, during, and after a snowfall event in urban, industrial, suburban, and rural areas of Nanjing city in eastern China, for both chemical composition analysis and cytotoxicity tests. After 24 h exposure to these PM 2.5 , the cell activity, oxidative stress indicators and inflammatory factor expression levels of human lung epithelial cells A549 were measured by ELISA, and DNA damage was determined by comet assay. Although the concentrations of PM 2.5 in the air were reduced during snowfall, they posed stronger cytotoxicity, genetic toxicity and inflammatory responses to A549 cells. Related to the elevated mass concentrations of some components accumulated in PM 2.5 during snowfall, As, Co, Cr, Sr, V, water-soluble Na + and Ca 2+ showed positive correlations with toxicity indicators. Therefore, snowfall will clean air by deposition, but also make the PM 2.5 components remaining in air mostly anthropogenic by covering ground soil/dust, thus increase the particle's mass-based cytotoxicity and their health risks still cannot be ignored, such as the heavy metals and water-soluble ions from automobile exhaust and coal combustion., 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 © 2020 Elsevier B.V. All rights reserved.)

The increase in the surface ozone (O 3 ) concentration causes air pollution, which has become a significant environmental issue that is of increasing concern. Ozone pollution not only directly harms human health, but also influences the agricultural ecosystem by impacting crop growth, which may then indirectly affect human health through food quality and the safety of agricultural products. The effects of O 3 pollution on rice growth, yields, and mineral metal contents in grains were investigated through field experiments with increased O 3 concentration treatment (remaining at 100 nL·L -1 ) in open top chambers (OTC). The crop growth and metal contents of two rice varieties were analyzed and compared. The results showed that the higher O 3 concentration inhibited the photosynthesis of Nanjing 5055 and Yangdao 6 rice leaves, reduced the chlorophyll content and leaf area index, and subsequently led to a decline in the rice yield of 45.5% and 28.6%, respectively. However, compared with the natural control, the contents of most mineral metallic elements in the brown rice and glume of the harvested grains increased by 3.6%-19.8% and 3.9%-36.0%, respectively, thus resulting in a lack of essential trace elements or pollution of heavy metals; hence, the impact of O 3 on rice food quality and safety requires a comprehensive evaluation.

The atmospheric fine particulate matters (PM 2.5 ) induce significant negative effects on human health, such as in the form of oxidative stress and pro-inflammatory response. Organic pollutants are important harmful and toxic compositions in PM 2.5 , risks of which usually show temporal and spatial variations. To investigate the toxic effects of airborne organic pollutants on human lung epithelial cells A549, the PM 2.5 samples were collected monthly from both urban and industrial areas during a whole year in Nanjing, eastern China. After exposure to organic components extracted from these PM 2.5 , the cell viability, lactate dehydrogenase content, oxidative stress index level and inflammatory factor expression level were measured. Supported by the concentrations of polycyclic aromatic hydrocarbons (PAHs) and n-alkanes, results showed that, organic components of PM 2.5 from cold season (winter and spring) typically influenced cell membrane, cell oxidation and inflammatory damage, while the urban samples of warm season (summer and autumn) impacted cell viability more prominently. Spatially, the toxicity of samples from industrial sources was generally stronger than that from urban source, but urban samples induced much stronger damage to cell membranes than industrial one. The correlations between the PAHs, n-alkanes contents and toxicity parameters indicated that, the airborne organic components derived from motor vehicle exhaust and coal combustion were possibly the key toxic sources., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Atmospheric fine particulate matters (PM 2.5 ) induce adverse human health effects through inhalation, and the harmful effects of PM 2.5 are determined not only by its air concentrations, but also by the particle components varied temporally. To investigate seasonal differences of the aerosol toxicity effects including cell viability and membrane damage, cell oxidative stress and responses of inflammatory cytokines, the human lung epithelial cells (A549) were exposed to PM 2.5 samples collected in both summer and winter by the in vitro toxicity bioassays. Toxicological results showed that, the PM 2.5 led to the cell viability decrease, cell membrane injury, oxidative stress level increase and inflammatory responses in a dose-dependent manner. Temporally, the cytotoxicity of winter PM 2.5 was higher than summer of this studied industrial area of Nanjing, China. According to the different contents of heavy metals accumulated in PM 2.5 , the transition metals such as Cu might be an important contributor to the aerosol cell toxicity., (Copyright © 2018 Elsevier Inc. All rights reserved.)