[Input Characteristics of Dry Deposition of Atmospheric Particulates and Metals in Farmland in the Suburb of Nanjing].

The dry deposition of heavy metals in atmospheric particulates is one of the important sources of heavy metals in agricultural areas, but there are few observational studies on the atmospheric deposition of heavy metals in agricultural areas. In this study, the concentrations of atmospheric particulates with different particle sizes and ten kinds of metal elements in them were analyzed by sampling a typical rice-wheat rotation area in the suburb of Nanjing for one year, and the dry deposition fluxes were estimated using the big leaf model, so as to understand the input characteristics of particulates and heavy metals. The results showed that the particulate concentrations and dry deposition fluxes were high in winter and spring but low in summer and autumn. In winter and spring, coarse particulates (2.1-9.0 µm) and fine particulates (<2.1 µm) had dual effects on particulate pollution, whereas in summer and autumn, particulate pollution was mainly attributed to the fine particulates. The concentrations of metal elements were the lowest in giant particulates (>9.0 µm) and were similar in coarse particulates and fine particulates, whereas Pb, Mn, As, and Cd elements were relatively high in fine particulates. The average annual dry deposition fluxes[g·(m2·a)-1] of particulates was giant particulates (8.31)>coarse particulates (5.99)>fine particulates (0.629). The order of average annual dry deposition fluxes[mg·(m2·a)-1] of the 10 metals was Ca(2096.4)>Al(1710.4)>Zn(855.0)>Fe(256.1)>Pb(40.35)>Cu(31.93)>V(26.21)>Mn(9.10)>As(2.48)>Cd(0.28). The average annual dry deposition fluxes of the 10 metal elements in fine particulates, coarse particulates, and giant particulates were 179.03, 2124.97, and 2724.18 mg·(m2·a)-1, respectively. These results will provide a reference for a more comprehensive understanding of the impact of human activities on the quality and safety of agricultural products and soil ecological environment.

Deposition of trace metals associated with atmospheric particulate matter: Environmental fate and health risk assessment.

Anthropogenic and natural sources influence trace metals (TMs) bound to different sized particulate matter (PM) in dry and wet atmospheric deposition, which can create ecosystem and human health issues in the long run. Limited reviews are available summarizing worldwide concentrations in TMs in atmospheric PMs, their sources and pathways. Simultaneously, quantitative assessment of the potential human and ecosystem health risks imposed by the atmospheric particulate matter has not been adequately reviewed. Addressing this gap, here we review, the concentration of TMs in dry deposition mainly varies with the responsible sources, whereas, in wet deposition, it depends on the solubility of TMs. Other than deposition on impervious surfaces, the TMs incorporated PM can be deposited on biological agents. Health risk assessments show that ingestion and dermal contact pathways are more likely to cause health issues, however, the probability of occurring ingestion and dermal contact pathways is limited. Attention must be paid to the contribution from non-exhaust and exhaust vehicular emissions for TMs in atmospheric deposition, understanding their impact on stormwater management and urban agriculture. Behaviors of TMs in the atmosphere depends on many complex factors including origin, wind patterns, and weather conditions. Therefore, future research needs to be carried to model and predict the fate and transfer of TMs once they are generated through natural and anthropogenic sources. We believe that such research would allow establishing pollution control policies and measures in urban environments which will be critical to reduce the levels of TMs associated with atmospheric deposition in the environment.

Phytic acid functionalized magnetic adsorbents for facile enrichment of trace rare earth elements in environmental water, digested atmospheric particulates and the extracts followed by inductively coupled plasma mass spectrometry detection.

Phytic acid (PA) functionalized magnetic adsorbents was synthesized through simple process. The functionalized sorbents are featured with core-shell structure, good magnetism, chemical stability, selectivity, and fast adsorption/desorption dynamics for the preconcentration of trace rare earth elements (REEs). With the aid of inductively coupled plasma mass spectrometry detection, the prepared Fe3O4@SiO2@PA sorbents were employed for the separation and enrichment of 15 REEs from environmental water and atmospheric particulates with different sizes. Under the optimal conditions, the method presented an enrichment factor of 300-fold and low detection limits (0.002-1.1 ng/L) for 15 REEs, with the relative standard deviations of 1.4-4.4%. Environmental water samples were analyzed by the proposed method, and 15 REEs of 0.08-5.80 ng/L were found in local rainwater and river water. The REEs concentration in locally collected fine particulate matter was 0.01-0.93 ng/m3, 0.03-1.70 ng/m3 and 0.03-2.47 ng/m3 of REEs were found in inhalable particulate matter and total suspended particulate samples, respectively. The bioaccessibility of REEs in PM2.5 was evaluated by using Gamble's solution extraction, which was calculated to be 0.73-5.46%.

Effects of water-soluble components of atmospheric particulates from rare earth mining areas in China on lung cancer cell cycle.

BACKGROUND: This study aims to investigate the effects of water soluble particulate matter (WSPM) on the viability and protein expression profile of human lung adenocarcinoma cell A549 in the Bayou Obo rare earth mining area, and explore the influence of WSPM on the A549 cell cycle. RESULTS: It was found that WSPM can inhibit the viability of A549 cells and induce cell arrest in the G2/M phase. Compared with controls, exposure to WSPM10 and WSPM2.5 induced 134 and 116 proteins to be differentially expressed in A549 cells, respectively. In addition, 33 and 31 differentially expressed proteins were further confirmed, and was consistent with the proteomic analysis. The most prominent enrichment in ribosome-associated proteins were presented. When RPL6, RPL13, or RPL18A gene expression was inhibited, A549 cells were arrested in the G1 phase, affecting the expression of Cyclin D1, p21, RB1, Cyclin A2, Cyclin B1, CDC25A, CDK2, CHEK2 and E2F1. Furthermore, the La3+, Ce3+, Nd3+ and F- in WSPM also inhibited the viability of A549 cells. After 24 h of exposure to 2 mM of NaF, A549 cells were also arrested in the G2/M phase, while the other three compounds did not have this effect. These four compounds affected the cell cycle regulatory factors in A549 cells, mainly focusing on effecting the expression of CDK2, CDK4, RB1, ATM, TP53 and MDM2 genes. These results are consistent with the those from WSPM exposure. CONCLUSIONS: These results revealed that WSPM from rare earth mines decreased the viability of A549 cells, and induced cell cycle G2/M phase arrest, and even apoptosis, which may be independent of the NF-κB/MYD88 pathway, and be perceived by the TLR4 receptor. The dysfunction of the cell cycle is correlated to the down-expression of ribosomal proteins (RPs). However, it is not the direct reason for the A549 cell arrest in the G2/M phase. La3+, Ce3+, and F- are probably the main toxic substances in WSPM, and may be regulate the A549 cell cycle by affecting the expression of genes, such as MDM2, RB1, ATM, TP53, E2F1, CDK2 and CDK4. These results indicate the importance for further research into the relationship between APM and lung cancer.

A new type of electron microscope rapid collection device for atmospheric particles and its application cases.

A device for collecting atmospheric particulates matter for on-line electron microscopy was designed and manufactured by using 3D modeling and printing technology. The device was used to collect atmospheric particulates matter in Xining city of Qinghai province for seven consecutive days and used to collect atmospheric particulates matter in Jinan city of Shandong province for 30 consecutive days. And the samples were analyzed by electron microscopy. Through it can obtain ultra structure and size distribution information of atmospheric particulates matter. The experimental results reflected the distribution of atmospheric particulate matter in real time. The on-line acquisition device for electron microscopy is practical, fast, and convenient, which greatly shortens the sampling period and can be carried to any place outdoors for real-time sampling. The morphological structure and particle size distribution of atmospheric particles in sampling area was observed by electron microscope. The device has reference value to the study of PM2.5 and PM10 in atmosphere and air pollution. This acquisition device is convenient for the detection of sample by electron microscopy. It can further expand and simplify the sampling technology of large-scale instruments and equipment. This new method of real-time monitoring of air pollution is worth popularizing and applying.

Distribution characteristics of microbial community structure in atmospheric particulates of the typical industrial city in Jiangsu province, China.

In this study, Xuzhou, a typical industrial city in the north of Jiangsu Province, was chosen to investigate the pollution level of atmospheric particulates. The proportion of fine particles (PM2.5) in PM10 is larger than that of coarse particles (about 58%). The physicochemical properties of PM2.5 were analyzed by SEM and EDS. DGGE was used to study the distribution characteristics of bacterial community structure on atmospheric particulates (TSP, PM2.5 and PM10) in different functional areas of Xuzhou city during the winter haze. It was found that the microbial populations of atmospheric particles were mainly divided into three groups: Proteobacteria, Bacteroidetes, and Pachytenella. The community structure of bacteria in fine particle size was more abundant than that in coarse particle size. When haze occurs, the concentration of all kinds of pathogens in fine particle size will increase. Therefore, it is necessary to focus on the monitoring and management of fine particles.

Effects of atmospheric particulates exposure on Nrf2 signaling pathway and inflammatory factors in myocardium of rats fed with high-fat and high-glucose diet / 上海预防医学

Objective To study the effect of atmospheric particulate exposure on the expression of key molecules of Nrf2 signaling pathway involved in oxidative stress and inflammatory response factors in myocardium of rats fed with high-fat and high-glucose diet. Methods A total of 48 SD male rats were randomly divided into control group (CC group), high-fat and high-glucose diet group (HC group), atmospheric particulates group (CP group) and atmospheric particulates plus high-fat and high-glucose diet group (HP group), with 12 rats in each group.Rats were fed in individual ventilated cages (IVC).The CC and HC groups were placed in IVCs equipped with the atmospheric particulate filter, however, the CP and HP groups without the atmospheric particulate filter to make the air composition similar to the outdoor.A total of 24 rats were sacrificed for acquiring myocardial tissue after 3 and 6 months of exposure.The mRNA expression of Nrf2, HO-1, NQO1, VCAM-1 and MCP-1 were measured using RT-qPCR and the protein expression of VCAM-1, MCP-1 detected using western blot. Results The mRNA expression levels of Nrf2, HO-1, NQO1, VCAM-1 and MCP-1 and the protein expression levels of VCAM-1 and MCP-1 in HC, CP and HP groups were higher than CC group (P < 0.05).The mRNA expression levels of Nrf2, HO-1, NQO1, VCAM-1, MCP-1 and the protein expression levels of VCAM-1, MCP-1 in the HP group were higher than HC and CP groups (P < 0.05).The mRNA expression levels of Nrf2 in CP and HP groups after 6 months of exposure were lower than that at 3 months (P < 0.05). Conclusion The exposure of atmospheric particles, high-fat and high-glucose and their combination diets could cause myocardial tissue inflammatory responses, and activate Nrf2 signaling pathways to protect against myocardial damage.

Winter chemical partitioning of metals bound to atmospheric fine particles in Dongguan, China, and its health risk assessment.

To analyze the relationship between nanoparticles and the chemical forms in an urban atmospheric environment, metallic particles with different diameters were collected using a nanoparticle sampling system and analyzed for chemical and morphological characteristics, bioactivity, and the risk of carcinogenic and non-carcinogenic effects. The source of the atmospheric particles was analyzed based on the enrichment factor method, and the carcinogenicity of the atmospheric particles was analyzed using the health risk model. The partition contents of metals extractable by a weak acid, including As, Ca, Cd, Cs, Pb, Sr, and Zn, were in a range of 32.17-71.4%, with an average value of 47.07%. The content of oxides and reducible metals of all of the elements was generally low. Potassium was distributed mainly in the residual and weak-acid-extractable fractions. Barium had a high proportion of the oxidation state. Each fraction of Zn was basically the same, while the content of the weak-acid-extractable fraction was slightly higher. We found bio-access potential to be positively correlated with a high proportion of the weak acid extracts such as Mg, Sr, and Zn. We also found there to be a large weak-acid-extractable fraction (F1) and residual fraction (F4) and relatively enriched elements and strongly enriched elements, which means F1 and F4 may be the cause of enrichment. The hazard index (HI) and the total cancer risk (TCR) were far beyond the safety threshold when the diameter of the particle was in the range of 0.1-0.5 µm, indicating that the residents in Dongguan city were experiencing obvious non-carcinogenic and carcinogenic risks.

[Particle Size Distribution and Human Health Risk Assessment of Heavy Metals in Atmospheric Particles from Beijing and Xinxiang During Summer].

Under a condition of good air quality (AQI:55-90, PM10:37-97 µg·m-3, PM2.5:17-76 µg·m-3), six groups of 54 samples were collected using an Andersen cascade impactor from both the indoor and outdoor stations in Beijing and Xinxiang from June to August in 2016. The samples were digested by microwave digestion, and nine heavy metal elements (Pb, Cr, Ni, Cu, Zn, As, Cd, Mn, and Co) in the atmospheric particles were determined with an inductively coupled plasma source mass spectrometer (ICP-MS). The results showed that the enrichment index (0-3) of most elements were low in both cities except for Cd[15.0 (Beijing) and 8.47 (Xinxiang)]. Cr, Co, Cu, and Mn in the atmospheric particles from Beijing park, Cd, Pb, and Mn in the atmospheric particles from the Beijing office, Cr, Co, Ni, and As in the atmospheric particles from Xinxiang park, and all nine heavy metal elements in the atmospheric particles from roads in both cities were found to be more concentrated in the coarse fractions; however, Pb, Zn, Cd, Ni, and As in the atmospheric particles from Beijing park, Co, Zn, Ni, Cr, As, and Cu in the atmospheric particles from the Beijing office, Pb, Zn, Cd, Cu, and Mn in the atmospheric particles from Xinxiang park, and all nine metal elements in the atmospheric particles from the Beijing office showed the opposite pattern. The result of a human health risk assessment indicated that the carcinogenic risk of the five carcinogenic elements were all less than 10-4, but a lower potential cancer risk would also occur under long term exposure. For the four non-carcinogenic elements (Pb, Zn, Mn, and Cu), the non-carcinogenic health risk values of Pb, Zn, Mn, and Cu in the atmospheric particulates in Beijing were all far less than 1, which means the corresponding non-carcinogenic risk was negligible; and, except for Mn, there was no obvious non-carcinogenic risk from Pb, Zn, and Cu in the atmospheric particles of Xinxiang.

A Specific Turn-On Fluorescent Sensing for Ultrasensitive and Selective Detection of Phosphate in Environmental Samples Based on Antenna Effect-Improved FRET by Surfactant.

Phosphate is not only an important indicator for aquatic ecosystems, but also plays vital roles in biosystems. A new strategy for ultrasensitive and selective detection of phosphate is fabricated based on a new insight found in this paper, in which a lower concentration of surfactant sodium dodecylbenzenesulfonate (SDBS) can greatly induce fluorescence resonance energy transfer (FRET) from ciprofloxacin (CIP) to Eu3+ in the CIP-Eu3+ complex. Surfactant SDBS does not act as a sensitizer for enhancing the fluorescence intensity of the system, but acts as a sensitizer of FRET and makes the native fluorescence of CIP quenched completely (switch off). Eu3+ ions can coordinate with the oxygen-donor atoms of phosphate, which weakens FRET from CIP to Eu3+ and results in the fluorescence recovery of CIP (turn on). The multicomplex of the CIP-Eu3+-phosphate has more sensitive fluorescent response than that of the reported coordination nanoparticle-based fluorescent probes. The LOD (S/N = 3) of this sensing system can attain 4.3 nM. The possible interferential substances existing in environmental samples, such as 17 common metal ions, 11 anions, and fulvic acid investigated, do not interfere with the phosphate detection. This sensing system has been successfully applied for phosphate detection in environmental samples such as wastewater, surface water, and atmospheric particulates. This work not only develops a fluorescent probe for the phosphate detection, but also provides a new strategy for designing fluorescent probes based on FRET or coordination nanoparticles.

Provenance and environmental risk of windblown materials from mine tailing ponds, Murcia, Spain.

Atmospheric particulates play a vital role in the transport of potentially toxic metals, being an important exposure pathways of people to toxic elements, which is faster and can occur in a much larger scale than water, soil and biota transport. Windblown materials in abandoned tailing ponds have not been well examined. The objectives of this investigation were: to study the major physical and geochemical properties of the materials eroded by wind inside the tailing ponds, and to understand the relative contribution of different sources to its heavy metals concentration. Study area is located in Cartagena-La Union mining district (SE Spain), where metallic mining of Fe, Pb and Zn has been developed for more than 2500 years. Wind-eroded particulates were monthly collected at 3 different heights (20, 50, and 80 cm) from the ground for a period of a full year using 4 dust collectors. Four tailing samples and 4 surface soil samples from the surrounding hills were also taken. Dust, soil, and tailing samples were examined for pH, particle size distribution, electrical conductivity, calcium carbonate content, Pb, Cu, Zn, Cd, Mn, Co, Ni, Ti and Zr concentrations. The results indicated that very coarse textured, slightly saline, and almost neutral wind-eroded deposits were generated with a very high temporal variability throughout the year. They also showed that the concentration of Cd, Mn, Pb and Zn, in the dust samples is extraordinarily high (18, 1254, 1831, and 5747 mg kg-1 respectively), whereas Co, Ni, and Cu had concentrations into the range of background concentrations found in the Earth's crust (3.8, 12, and 60 mg kg-1 respectively). Besides, the concentration of both categories of heavy metals in the dust samples was higher than that in tailing and less than that of the soils. The barren surfaces of tailing ponds and also the surface soils of the surrounding area seem to be the major contributors to the dust collected. Therefore, abandoned mines as well as their tailing ponds should be rehabilitated by proper technologies and then well stabilized and/or covered by appropriate plant vegetation to control the transfer, particularly by air, of environmentally hazardous materials to other areas.

Capacity of six shrub species to retain atmospheric particulates with different diameters.

Garden plants can absorb and retain atmospheric particles and are important for remediating environmental pollution. In this study, the dust retention characteristics of six typical shrub species were measured in the greenbelt of a road in the Chengyang District of Qingdao, China, and the maximum capacity for dust retention of each species was determined. The different diameters and areas occupied by particulate matter (PM) were analyzed on the leaf surfaces of the plants. Based on the results for the six shrub species, the rank order of average content of dust retention per unit leaf area was Euonymus japonicus > Pyracantha fortuneana > Ligustrum vicaryi > Amygdalus triloba > Ligustrum sinense > Forsythia suspensa, whereas the rank order of average content per unit volume was E. japonicus > A. triloba > P. fortuneana > L. vicaryi > L. sinense > F. suspensa. The maximum content of dust retention per unit leaf area was reached in approximately 24 days. Plants retained atmospheric PM primarily on the upper leaf surfaces. The primary portion of particles on the leaves was PM10 (over 80%), and PM2.5 was the principal component of PM10. Leaf surface structure significantly affected the abilities of plants to retain PM, and the plants with a thick wax layer or large and dense stomata adsorbed more PM, such as E. japonicus. This study provides a scientific basis for the capacity of landscape plants to retain different diameter particulates.

Determination of Amines in Particulate Matter by Gas Chromatography-Mass Spectrometry / 分析化学

A method was developed for determination of thirteen amines including seven aliphatic amines, two heterocyclic amines and four aromatic amines in atmospheric particulate matter (PM) by gas chromatography-mass spectrometry (GC-MS). Samples were ultrasonically extracted with ultra-pure water and derivatized with benzenesulfonyl chloride (BSC) under alkaline conditions. The derivatives were extracted with dichloromethane and then detected by GC-MS using DB-5MS chromatographic column. The method detection limit (S/N=3) and quantitation limit (S/N=10) were 0.00008-0.017 μg/mL and 0.00026-0.0565 μg/mL respectively, and the correlation coefficients were 0.9903-0.9996, which indicated that the standard curve had good linear correlation. In addition, the relative standard deviation was less than 30％ and the average recovery was 54.4％-159.7％ except for methylamine and benzylamine at spiked level of 1.0 μg/mL, showing high precision and accuracy. 9 kinds of amines were detected in the PM2.5 samples collected in Guangzhou city by this method, among which dimethylamine and butylamine accounted for 90％ of the total nine amines, which indicated that they were primary amines in PM2.5; while propylamine exhibited the lowest level in PM2.5 with the concentration less than 1.0 ng/m3.

[Characteristics of the Size Distribution of Water Soluble Inorganic Ions During a Typical Haze Pollution in the Autumn in Shijiazhuang].

To characterize the size distribution of water soluble inorganic ions (WSⅡ) in haze days, particle samples were collected by an Andersen cascade impactor in Shijiazhuang from October 15 to November 14 in 2013, and the concentrations of eight kinds of WSⅡ (Na+, NH4+, K+, Mg2+, Ca2+, Cl-, NO3-and SO42-) during a typical haze episode were analyzed by ion chromatography. Sources and formation mechanism of WSⅡ were analyzed based on their size distributions. The results showed that Shijiazhuang suffers serious air pollution during the autumn season. The daily average concentrations of PM10and PM2.5were (361.2±138.7) µg·m-3 and (175.6±87.2) µg·m-3 and the daily average concentration of PM2.5was 2.3 times as high as the national secondary standard. The total water soluble inorganic ion concentrations (TWSⅡ) in clean days, light haze days and heavy haze days were(64.4±4.6)µg·m-3, (109.9±22.0)µg·m-3 and (212.9±50.1) µg·m-3 respectively. In addition, the ratio of secondary inorganic ions (SNA:SO42-, NO3- and NH4+) in TWSⅡ increased from 44.9% to 77.6% as changed from clean days to the heavy haze days, suggesting the evolution of haze episodes mainly originated from the formation and accumulation of SNA. The size distributions of SO42-, NO3- and NH4+ were bimodal in clean days, peaking at 0.43 -0.65 µm and 4.7-5.8 µm, respectively, which changed to unimodal distribution in both the light and heavy haze days, peaking at 0.65-1.1 µm. Owing to high humidity during the heavy haze days, the aqueous phase reactions of SO42- and NO3- were likely promoted, which led to the transformation of condensation mode in clean days to the droplet mode in haze days. The size distributions of Na+, Mg2+ and Ca2+ were different with that of SNA, which showed a coarse mode peaking at 4.7-5.8 µm both in clean and haze days, whereas K+and Cl- showed a bimodal distribution both in clean and haze days, although the modal size was different in clean and haze days.