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assessment of heavy metal pollution characteristics and human health risk of exposure to ambient PM_(2.5) in Tianjin,China

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Particuology 2015年第3期13卷 104-109页

作者： Peifei Chen Xiaohui Bi Jiaqi Zhang Jianhui Wu Yinchang Feng College of environmental Science and Safety Engineering Tianjin University of Technology College of environmental Science and Engineering Nankai University

To examine the features of heavy metal pollution of PM2.5 （particulate matter less than 2.5 μm） in Tianjin, China, as well as the exposure risk of PM2.5 to human health, we analyzed ambient PM2.5samples collected from a campus of Nankai University in June, August, and October 2012. The concentrations of PM2.5 and heavy metals （Ni, Cu, Pb, Zn, Cr, Cd, Hg, As and Mn） in PM2.5 were analyzed by gravimetric analysis and inductively coupled plasma-mass spectrometry, respectively. The results show that the heavy metals contained in PM2.5 were, in descending order, Cu, Zn, Pb, Mn, Cr, Ni, Cd, As, and Hg. The proportion of Cd exceeded the secondary level of National Ambient Air Quality Standard of China （GB 3095-2012） by 1.3 times, while others were within the limit. Enrichment factor analysis indicated that Cu, Zn, Cd, Pb, and Hg are mainly from anthropogenic sources. Principal component analysis indicated that the main sources of the heavy metals are vehicle exhaust, chemical waste, and coal-burning activities. The nine heavy metals which may cause health issues by exposure through the human respiratory system and should be further examined are Cr, Cd, As, Ni, Cu, Pb, Mn, Zn, and Hg, in the order of decreasing risk levels. With reference to the U.S. EPA standard the risk levels of all nine metals were below the acceptable level （10 6/year）.

关键词： PM2.5 Heavy metalEnrichment factorPrincipal component analysisHealth risk assessment

Source apportionment of PM_(2.5)using PMF combined online bulk and single-particle measurements:Contribution of fireworks and biomass burning

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Journal of environmental Sciences 2024年第2期136卷 325-336页

作者： Yanjing Zhang Wenshuai Li Lei Li Mei Li Zhen Zhou Jianzhen Yu Yang Zhou Frontier Science Center for Deep Ocean Multispheres and Earth System(FDOMES)and Physical Oceanography Laboratory Ocean University of ChinaQingdaoShandong 266100China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdaoShandong 266100China institute of Atmospheric Environment Safety and Pollution Control Jinan UniversityGuangdong 510632China institute of Environment Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Department of Chemistry Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Division of Environment The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina

Fireworks(FW)could significantly worsen air quality in short term during *** to similar tracers with biomass burning(BB),the fast and precise qualification of FW and BB is still *** this study,online bulk and single-particle measurements were combined to investigate the contributions of FW and BB to the overall mass concentrations of PM_(2.5)and specific chemical species by positive matrix factorization(PMF)during the Chinese New Year in Hong Kong in February *** combined information,fresh/aged FW(abundant ^(140)K_(2)NO_(3)^(+)and ^(213)K_(3)SO_(4)^(+)formed from ^(113)K_(2)Cl^(+)discharged by fresh FW)can be extracted from the fresh/aged BB sources,in addition to the Second Aerosol,Vehicles+Road Dust,and Sea Salt *** contributions of FW and BB were investigated during three high particle matter episodes influenced by the pollution transported from the Pearl River Delta *** fresh BB/FW contributed 39.2%and 19.6%to PM_(2.5)during the Lunar Chinese New Year ***,the contributions of aged FW/BB enhanced in the last two episodes due to the aging process,evidenced by high contributions from secondary ***,the fresh BB/FW showed more significant contributions to nitrate(35.1%and15.0%,respectively)compared with sulfate(25.1%and 5.9%,respectively)and OC(14.8%and11.1%,respectively)on *** comparison,the aged FW contributed more to sulfate(13.4%).Overall,combining online bulk and single-particle measurement data can combine both instruments’advantages and provide a new perspective for applying source apportionment of aerosols using PMF.

关键词： Source apportionment PMF Online bulk measurements Single particle analysis Fireworks Biomass burning

Comparative Study of the Structure and Properties of Ti—O-based Nanowire Films Prepared by Anodization and Chemical Oxidation Methods

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Journal of Materials Science & Technology 2014年第9期30卷 878-883页

作者： Xinwen Huang Zongjian Liu Resource & Environment Catalysis institute College of Chemical Engineering and Materials ScienceZhejiang University of Technology College of Biological and environmental Engineering Zhejiang University of Technology

Net-like titanium oxide or H-titanate nanowire films were grown on Ti substrates in 2 mol/L NaOH solutions at 80 ℃ via anodization method or chemical oxidation followed by proton-exchange. The microstructure, thermal stability and photoelectrochemical property of two types of films were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and photocurrent measurement. It is found that the anodic film mainly consists of a 500-nm-thick nenowire layer whereas the film formed by chemical oxidization is made up of two layers： a nanowire layer （nearly 1 tim in thickness） and an underlying non- nanowire layer （at least 1 μm in thickness）. In both two cases, the as-formed nanowires are partly crystallized. Thermal stability investigation reveals that the net-like structure of the anodic nanowire film almost keeps unchanged at a temperature less than 400℃ but is totally destroyed when being calcinated at 600 ℃. In contrast, the nanowire layer formed by chemical method is stable even after being calcinated at 600 ℃. Our results also show that the uncalcinated or calcinated anodic films are much more photoactive than the corresponding films prepared by chemical oxidization. The difference in photoelectrochemical property of two types of films is discussed based on their microstructures.

关键词： Anodization Nanowires Thin films Titanium dioxide Titanate

Photosynthetic Characterization of the Plant Dicranopteris dichotoma Bernh. in a Rare Earth Elements Mine

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Journal of Integrative Plant Biology 2005年第9期47卷 1092-1100页

作者： Li-Feng WANG Hong-Bing JI Ke-Zhi BAI Liang-Bi LI Ting-Yun KUANG Key Laboratory of Photosynthesis and environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China The Subcenter of the environmental Processes National Engineering Center for Urban environmental Pollution Control the Capital Normal University Beijing 100037 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

In order to investigate the distribution of rare earth elements （REEs） in the natural hyperaccumulator fern Dicranopteris dichotoma Bernh. and to characterize this plant photosynthetically, concentrations of REEs in D. dichotoma from mines mining heavy and light REEs （HREEs and LREEs, respectively）, as well as in D. dichotoma from an area in which no mining occurred, in southern Jiangxi Province were determined using inductively coupled plasma-mass spectrometry. The REE concentrations in the lamina of D. dichotoma were in the order LREEs mine 〉 HREEs mine 〉 non-mining area. The maximum REE content in the lamina of D. dichotoma from the LREE mine was approximately 2 648 mg/kg dry weight. The photosynthetic activity of D. dichotoma from areas of HREE and LREE mines was improved by the presence of high concentrations of REEs in the lamina compared with D. dichotoma from the non-mining area. However, this enhancement varied according to the concentrations of the REEs, as well as their type. In addition, 77K fluorescence, electron transport rate, and chlorophyll-protein complex studies showed that the enhancement of the photosynthetic activity of D. dichotoma from HREE mines was mainly due to an increase in the chlorophyll-protein complex of the reaction center of photosystem （PS） Ⅰ, whereas the enhancement observed in D. dichotoma from LREE mines was due to an increase in the internal antennae chlorophyll-protein complex of PS Ⅱ and greater light energy distribution to the light-harvesting chlorophyll-protein complex of PS Ⅱ.

关键词： chlorophyll-protein complex Dicranopteris dichotoma electron transport rate rare earth elements (REEs).

Risk assessment of Secondary Geological Disasters Induced by the Yushu Earthquake

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Journal of Mountain Science 2012年第2期9卷 232-242页

作者： NIU Quanfu CHENG Weiming LIU Yong XIE Yaowen LAN Hengxing CAO Yanrong College of Earth and environmental Science Lanzhou UniversityLanzhou 730000China State Key Laboratory of Resources and environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Gansu Provincial Electric Power Design institute Lanzhou 730000China

The Yushu Ms 7.1 earthquake occurred on April 14,2010 in Qinghai Province,*** induced a mass of secondary geological disasters,such as collapses,landslides,and debris *** assessment maps are important for geological disaster prevention and mitigation,and also can serve as a guide for post-earthquake ***,a hazard assessment index system of secondary geological disasters in the earthquake region was built in this paper,which was based on detailed analysis of environmental and triggering factors closely related to geological disasters in the study *** technology was utilized to extract and analyze the assessment *** assessment maps of secondary geological disasters were obtained by spatial modeling and overlaying ***,an analysis of the vulnerability of hazard bearing bodies in the area was conducted,important information,such as, population density,percentage of arable land, industrial and agricultural outputs per unit area were regarded as assessment indices to evaluate socioeconomic ***,the risk level of secondary geological disasters of the area was obtained by the formula:Risk=Hazard×Vulnerability. Risk assessment maps were categorized into four levels,including"low","moderate","high"and"very high".These results show that some urban areas are at very high risk,including Jiegu,Chengwen,Xiaxiula and Sahuteng *** research can provide some references and suggestions to improve decisionmaking support for emergency relief and post- earthquake reconstruction in the study area.

关键词： Yushu Earthquake Secondary geological disasters (SGD) Hazard assessment Socio-economic vulnerability Risk assessment

Effects of mesenchymal stem cell on dopaminergic neurons,motor and memory functions in animal models of Parkinson's disease:a systematic review and meta-analysis

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Neural Regeneration Research 2024年第7期19卷 1584-1592页

作者： Jong Mi Park Masoud Rahmati Sang Chul Lee Jae Il Shin Yong Wook Kim Department and Research institute of Rehabilitation Medicine Yonsei University College of MedicineSeoulSouth Korea Department of Physical Education and Sport Sciences Faculty of Literature and Human SciencesLorestan UniversityKhoramabadIran Department of Pediatrics Yonsei University College of MedicineSeoulSouth Korea

Parkinson’s disease is chara cterized by the loss of dopaminergic neurons in the substantia nigra pars com pacta,and although restoring striatal dopamine levels may improve symptoms,no treatment can cure or reve rse the disease *** cell therapy has a regenerative effect and is being actively studied as a candidate for the treatment of Parkinson’s *** stem cells are considered a promising option due to fewer ethical concerns,a lower risk of immune rejection,and a lower risk of *** performed a meta-analysis to evaluate the therapeutic effects of mesenchymal stem cells and their derivatives on motor function,memory,and preservation of dopamine rgic neurons in a Parkinson’s disease animal *** searched bibliographic databases(PubMed/MEDLINE,Embase,CENTRAL,Scopus,and Web of Science)to identify articles and included only pee r-reviewed in vivo interve ntional animal studies published in any language through J une 28,*** study utilized the random-effect model to estimate the 95%confidence intervals(CI)of the standard mean differences(SMD)between the treatment and control *** use the systematic review center for laboratory animal expe rimentation’s risk of bias tool and the collaborative approach to meta-analysis and review of animal studies checklist for study quality assessment.A total of 33studies with data from 840 Parkinson’s disease model animals were included in the *** with mesenchymal stem cells significantly improved motor function as assessed by the amphetamine-induced rotational *** the stem cell types,the bone marrow MSCs with neurotrophic factor group showed la rgest effect size(SMD[95%CI]=-6.21[-9.50 to-2.93],P=0.0001,I^(2)=0.0%).The stem cell treatment group had significantly more tyrosine hydroxylase positive dopamine rgic neurons in the striatum([95%CI]=1.04[0.59 to 1.49],P=0.0001,I^(2)=65.1%)and substantia nigra(SMD[95%CI]=1.38[0.89 to 1.87],P=0.0001,I^(2)=75.3%),indicating a

关键词： animal animal experimentation mesenchymal stem cells models Parkinson’s disease stem cell transplantation

Heavy metals in maternal and cord blood in Beijing and their efficiency of placental transfer

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Journal of environmental Sciences 2019年第6期31卷 99-106页

作者： Aijing Li Taifeng Zhuang Jianbo Shi Yong Liang Maoyong Song institute of Environment and Health Jianghan University Key Laboratory of environmental Nanotechnology and Health Effects Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Department of Pediatrics Beijing Obstetrics and Gynecology Hospital Capital Medical University University of Chinese Academy of Sciences

This study aimed to determine the effect of exposure to heavy metals in pregnant women in Beijing, China. We also evaluated the association of these heavy metals with birth weight and length of newborns. We measured the levels of 10 heavy metals,including lead(Pb), titanium(Ti), manganese(Mn), nickel(Ni), cadmium(Cd), chromium(Cr), antimony(Sb), stannum(Sn), vanadium(V), and arsenic(As), in 156 maternal and cord blood pairs. An inductively coupled plasma mass spectrometry method was used for measurement. Pb, As, Ti, Mn, and Sb showed high detection rates(> 50%) in both maternal and cord blood. Fourteen(9%) mothers had blood Pb levels greater than the United States Center for Disease Control allowable threshold limit for children(50 μg/L).In prenatal exposure to these heavy metals, there was no significant association between any heavy metal and birth weight/length. Moreover, we estimated the placental transfer efficiency of each heavy metal, and the median placental transfer efficiency ranged from 49.6%(Ni) to 194%(Mn)(except for Cd and Sn). The level and detection rate of Cd in maternal blood were much higher than that in cord blood, which suggested that Cd had difficulty in passing the placental barrier. Prospective research should focus on the source and risk of heavy metals in non-occupationally exposed pregnant women in Beijing.

关键词： Heavy metal Maternal blood Cord blood Newborn Placental transfer efficiency

Cultivars and oil extraction techniques affect Cd/Pb contents and health risks in oil of rapeseed grown on Cd/Pb-contaminated farmland

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Frontiers of environmental Science & Engineering 2023年第7期17卷 119-131页

作者： Junmei Guo Yuexing Wei Junxing Yang Tongbin Chen Guodi Zheng Tianwei Qian Xiaona Liu Xiaofei Meng Mengke He College of environmental Science and Engineering Taiyuan University of TechnologyJinzhong 030600China Center for environmental Remediation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Substitute planting with rapeseed offers promise for safely using large areas of Cd/Pb-contaminated ***/Pb distributions during rapeseed oil production were investigated and health risks posed by the oil were *** were performed using three cultivars(Brassica rapa SYH and ZS100 and Brassica napus QY-1)and four oil extraction techniques(mechanical and low-temperature pressing and n-hexane and subcritical low-temperature butane extraction).The amounts of Cd and Pb in oil were 0.73%-8.44%and 3.14%-11.76%,respectively,of the amounts in rapeseed and were strongly affected by the cultivar and oil extraction *** heavy metal(HM)concentrations were lower in solvent-extracted oil(particularly subcritical low-temperature butane extracted oil,in which HMs were not detected)than mechanically pressed *** Cd and Pb transfer indices were lower(meaning larger proportions of HMs were retained by the rapeseed meal)for *** than *** was attributed to a high HM binding protein content of *** *** risks to humans were assessed using a probabilistic risk assessment *** carcinogenic risk was mainly(97.1%-99.9%)caused by Cd and poses more concern than non-carcinogenic *** health risks are posed by mechanically pressed than solvent-extracted oil,and higher carcinogenic risks are posed to people living in rural areas than urban *** planting with *** and extracting oil with organic solvent(preferably subcritical low-temperature butane)are optimal for safely utilizing Cd/Pb-contaminated *** should be paid to the health risks posed by Cd in oil to rural populations.

关键词： Rapeseed oil Oil extraction technologies Human health risk assessment Cd/Pb-contaminated farmland Substitute planting

The performance of the Noblesse multi-collector noble gas mass spectrometer for ^(40)Ar/^(39)Ar geochronology

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Acta Geochimica 2018年第5期37卷 734-745页

作者： Defeng He Finlay M.Stuart Dan N.Barfod Fang Xiao Hong Zhong State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Isotope Geoscience Unit Scottish Universities Environmental Research Centre NERC Argon Isotope Facility Scottish Universities Environmental Research Centre

Noblesse multi-collector noble gas mass spec- trometer is specially designed for multi-collection of Ar isotopes with different beam sizes, especially for small ion beams, precisely, and hence is perfectly suitable for ^40Ar/^39Ar geochronology. We have analyzed widely used sanidine, muscovite, and biotite standards with recom- mended ages of - 1.2-133 Ma, with the aim to assess the reliability of Noblesse for ^40Ar/^39Ar dating. An ESI MIR10 30W CO2 laser was used for total fusion or incremental heating samples. Extracted gases were routinely purified by four SAES NP10 getters （one at - 400 ℃ and others at room temperature）. A GP50 getter and a metal cold finger cooled by liquid N （- 196 ℃） were also attached for additional purification if necessary. The Ar isotopes were then measured by Noblesse using Faraday or multiplier according to the signal intensities. Over a period of 1.5 months 337 air calibrations produced a weighted mean ^40Ar/^36Ar of 296.50 ± 0.08 （2σ, MSWD = 4.77）. Fish Canyon sanidine is used to calculate J-values, which show good linear relationship with position in irradiation. The age of four mineral standards （Alder Creek sanidine, Brione muscovite, Yabachi sanidine, and Fangshan biotite） are within error of the accepted ages. Five Alder Creek sanidine aliquots yielded an age range of 1.174-1.181 ± 0.013 Ma （2σ） which broadly overlaps the established age of the standard and the uncertainty approaches those of the foremost Ar/Ar laboratories in the world. The weighted mean ages of four Brione muscovite aliquots （18.75 i 0.16 Ma, 2σ）, five Yabachi sanidine aliquots （29.50 ± 0.19 Ma, 2σ）, and three Fangshan bio- tite aliquots （133.0 ± 0.76 Ma, 2σ） are consistent with the recommended values of these standards, and the uncer- tainties are typical of modem Ar/Ar laboratories world- wide.

关键词： Ar/Ar geochronology Multi-collector Highprecision Noblesse Age standard