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Exposure of children to heavy metals from artisanal gold mining in Nigeria:evidences from bio-monitoring of hairs and nails

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Acta Geochimica 2020年第4期39卷 451-470页

作者： Adeniyi JohnPaul Adewumi Temitope Ayodeji Laniyan Tangfu Xiao yizhang liu Zengping Ning Department of Geological Sciences Achievers UniversityOwo.Ondo StateNigeria Department of Environmental Health Sciences College of MedicineUniversity of IbadanIbadanOyo StateNigeria Key Laboratory for Water Quality and Conservation of the Pearl River Delta Ministry of EducationGuangzhou UniversityGuangzhou 510006China School of Environmental Science and Engineering.Guangzhou University Guangzhou 510006China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

In recent times,there had been reported cases of Pb poisoning in Anka gold mining area,Northwest ***,this study was carried out to determine the extent of bioaccumulation of heavy metals in the hairs and nails of children in the *** samples(twenty nails and twenty hairs)samples were collected from ten boys and ten girls of ages 5–9 residing in the *** ascertain the sources of heavy metals in children,15 soils samples,15 groundwater samples,5 samples of mine tailings,and 5 plants samples were *** and nails of the subjects were collected using internationally acceptable *** samples were kept in uncontaminated ziplock bags prior to laboratory preparation and *** samples were cleaned using nonionic detergent(triton X-100)and deionized *** hairs and nails were digested with 10 mL of 6:1 mixture of nitric acid and perchloric *** soils,mine tailings,and plants were air-dried at room temperature,sieved,and chemically digested using the aqua regia *** concentrations of metals in all the samples were determined using highperformance liquid chromatography–inductively coupled plasma–mass *** analysis was employed to unravel potential sources of metals in the *** showed that heavy metals in children of the area are above results from similar studies and pathological ranges for heavy metals in hairs and ***,heavy metals in environmental media are above the recommended *** analysis showed that the metals are mainly from mining and other anthropogenic *** of correlation between heavy metals in hairs and nails with those in geological samples revealed that heavy metal that bioaccumulates in the children of this area are mostly from contaminated environmental *** is recommended that complete remediation and effective health education be carried out in the area.

关键词： Anka Bioaccumulation Children Heavy-metals Hairs Nails

Geochemical distribution, fractionation, and sources of heavy metals in dammed-river sediments: the Longjiang River, Southern China

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Acta Geochimica 2019年第2期38卷 190-201页

作者： Xiaolong Lan Zengping Ning yizhang liu Qingxiang Xiao Haiyan Chen Enzong Xiao Tangfu Xiao State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory for Water Quality and Conservation of the Pearl River Delta Ministry of Education School of Environmental Science and Engineering Guangzhou University

In the present study, six sediment cores were collected from six river-dammed reservoirs to reveal the geochemical distribution of heavy metals(As, Cd, Pb, Sb,and Zn) in the Longjiang River, South China, which is highly impacted by nonferrous metal mining and smelting activities. The sediments were geochemically characterized, combining geochemical analysis, sequential extractions, and210 Pb chronology. The results indicated that the river sediments were severely polluted by heavy metals in the order of Cd [ Zn & Pb & Sb [ As. These heavy metals generally exhibited relatively low enrichment in the upstream sediments because of the limited anthropogenic impact, but their abundances drastically increased in the midstream sediments due to local smelting activities. In downstream sediments, the heavy metal concentrations(except for Cd) decreased, owing to the effect of dam interception and detrital inputs. Cadmium levels tended to increase in downstream sediments, which were attributed to the intensive discharge of Cd during the pollution event in 2012. The sedimentary records were traced back to1985, and a significant decrease of heavy metal enrichments could be found after the year 2000, suggesting the enhancement of environmental management in this *** statistical results indicated that local metal smelting and mining activities were the main anthropogenic contributors for the enrichment of heavy metals in the dammed-river sediments. High enrichment factor and nonresidual fractions of heavy metals in local sediments may pose a direct threat to aquatic organisms. Cd presents significant danger because of its extreme enrichment and high labile fractions.

关键词： Heavy metals Fractionation 210pb dating Smelting and mining activities Sediment cores The Longjiang River

Cadmium isotope compositions of Fe-Mn nodules and surrounding soils: Implications for tracing Cd sources

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Fundamental Research 2021年第3期1卷 269-276页

作者： Ting Gao Yuhui liu Yafei Xia Jian-Ming Zhu Zhengrong Wang Meng Qi yizhang liu Zengping Ning Qiqi Wu Wenpo Xu Chengshuai liu State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China Department of Earth&Atmospheric Sciences City College of New YorkCUNYNew York 10031United States National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and ManagementInstitute of Eco-environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China CAS Center for Excellence in Quaternary Science and Global Change Xi'an 710061China

Cadmium (Cd) pollution in agricultural soils has become a severe threat to food security and human health in recent years. Stable Cd isotopes are a potentially powerful tool for identifying the sources of Cd in soils. However, many Earth surface processes, including adsorption, leaching, and biogeochemical cycles in plants, may generate Cd isotope fractionation, which can complicate the potential application of Cd isotopes in tracing the sources of Cd pollution in soils. In this work, the Cd isotope compositions of typical Fe-Mn nodules (FMNs) and surrounding soils in two different soil profiles are investigated. Our results show that the FMNs in lower layers (i.e., C and W horizons) are isotopically lighter than the surrounding soils by –0.114‰ to –0.156‰ (Δ114/110CdFMN-soil). We interpret this fractionation as the result of preferential adsorption of isotopically light Cd onto the surface of goethite. In the upper layers (i.e., P and A horizons), the Δ114/110CdFMN-soil values are more negative in the P horizon (–0.213‰ to –0.388‰) but more positive in the A horizon (0.061‰ to 0.204‰). We interpret these fractionations as the result of natural biogeochemical processes (i.e., leaching and biological cycling) during soil development. Soil leaching preferentially releases isotopically heavy Cd into the underlying soil (i.e., P horizon), shifting the topsoil towards lower δ114/110Cd values but the underlying soils towards higher δ114/110Cd values. Moreover, biological cycling contributes isotopically heavy Cd to the topsoil, probably shifting the topsoil towards higher δ114/110Cd values. Our study demonstrates that the formation of Fe oxyhydroxides, leaching, and biological cycling can considerably modify the soil Cd isotope signature, highlighting the need to consider natural biogeochemical processes when using Cd isotopes to trace heavy metal pollution in soils.

关键词： Cadmium isotopes Fe-Mn nodules Leaching Biological cycling

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“广州事件”与纳粹德国初期的对华政策

民国档案 2007年第1期 82-88页

作者：刘义章肖自力香港中文大学历史系华南师范大学历史文化学院

20世纪30年代前期希特勒上台之初,以著名投机商人克兰为中介,德国在广东进行了名为“广东项目”的大规模、持续性军事输出活动,从而在中德两国之间引发了一场旷日持久的“广州事件”。虽然克兰在广东的活动一再受到蒋介石南京国民政府... 详细信息

20世纪30年代前期希特勒上台之初,以著名投机商人克兰为中介,德国在广东进行了名为“广东项目”的大规模、持续性军事输出活动,从而在中德两国之间引发了一场旷日持久的“广州事件”。虽然克兰在广东的活动一再受到蒋介石南京国民政府的反对,德国一些重要军政人物也极力阻止克兰在广东冒险,但在军方及希特勒几度支持下,事件几经反复,一直持续到1936年。“广州事件”反映了希特勒上台的最初几年德国积极重整军备的国家战略及其对华政策的投机本质。

关键词：德国 “广州事件”广东项目对华政策克兰

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虚拟仿真实验在化工工艺学教学中的应用

湘南学院学报 2018年第2期39卷 77-80页

作者：刘义章滁州职业技术学院食品与环境工程系安徽滁州239001

通过对"化工工艺学"实践课程的分析,阐述虚拟仿真实验在该课程教学中的应用,同时结合实际教学中出现的问题,指出虚拟仿真实验在教学中应注意的几个方面,为教师更好地完成教学任务起到借鉴作用.

关键词：虚拟仿真化工工艺学实验教学

西南燃煤型地方病区煤炭和土壤中氟、钼的地球化学行为

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地球与环境 2021年第5期49卷 570-577页

作者：熊燕宁增平刘意章肖唐付贵阳学院生物与环境工程学院贵阳550005 中国科学院地球化学研究所环境地球化学国家重点实验室贵阳550081 广州大学环境科学与工程学院广州510006

氟和钼是广泛存在于表生环境中的人体必需微量元素,但过量摄入会影响人体健康,甚至会诱发地方性疾病。西南燃煤型地方病区部分煤炭和土壤中存在氟、钼富集的情况。本文系统介绍了氟和钼的元素地球化学行为特征和健康危害效应,综述了氟... 详细信息

氟和钼是广泛存在于表生环境中的人体必需微量元素,但过量摄入会影响人体健康,甚至会诱发地方性疾病。西南燃煤型地方病区部分煤炭和土壤中存在氟、钼富集的情况。本文系统介绍了氟和钼的元素地球化学行为特征和健康危害效应,综述了氟和钼在西南地区高氟高钼地质背景的燃煤型地方病区煤炭和土壤中的分布特征和赋存形态,分析了燃煤型地方病区煤炭开采、堆放和燃烧过程中氟和钼的迁移释放规律。研究认识对于高氟高钼地区氟、钼暴露及防控具有重要的科学价值和实际指导意义。

关键词：氟钼地球化学燃煤型地方病区

黑色岩系地质高背景区土壤锌富集特征与环境活性

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地球与环境 2022年第4期50卷 490-497页

作者：王春陈梓杰王莹刘意章刘承帅广东石油化工学院生物与食品工程学院广东茂名525000 中国科学院地球化学研究所环境地球化学国家重点实验室贵阳550081

锌(Zn)既是生物体必需元素又是有害元素,在复合污染的情况下,Zn在植物吸收、转运和富集镉的过程中发挥着重要作用。以往研究主要关注镉的活性,忽略了Zn的环境活性。基于此,本研究以黑色岩系地质高背景区自然富Zn土壤为对象,重点研究了土... 详细信息

锌(Zn)既是生物体必需元素又是有害元素,在复合污染的情况下,Zn在植物吸收、转运和富集镉的过程中发挥着重要作用。以往研究主要关注镉的活性,忽略了Zn的环境活性。基于此,本研究以黑色岩系地质高背景区自然富Zn土壤为对象,重点研究了土壤Zn的活性态和潜在活性态,讨论了Zn活性的影响因素和环境意义。结果表明,研究区土壤Zn富集,平均含量可达457 mg/kg,80%的土壤样品超过我国农用地土壤污染风险筛选值。CaCl_(2)提取态Zn含量平均值为0.92 mg/kg,平均提取率仅为0.26%,说明研究区土壤Zn的生物活性低,且随着pH升高而降低。EDTA提取态Zn的平均含量为12.7 mg/kg,平均提取率为2.74%,潜在有效态比例也较低。活性态在潜在活性态中占比为7.63%,活化潜力较大,且随着土壤pH的升高而降低。研究区土壤溶液中Zn∶Cd比较低,可能有利于植物对镉的吸收。开展土壤Zn活性的研究,对理解复合污染区土壤镉的活性变化及调控具有重要意义。

关键词：自然富集土壤重金属活性生物有效性

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镉同位素及其环境示踪

地球与环境 2015年第6期43卷 687-696页

作者：刘意章肖唐付朱建明中国科学院地球化学研究所环境地球化学国家重点实验室贵阳550081

随着多道接收电感耦合等离子体质谱仪(MC-ICPMS)的发展和广泛应用,镉(Cd)稳定同位素已成为当前非传统同位素地球化学的研究热点之一。本文对Cd同位素的分析方法、组成特征、变化规律、分馏机制及环境应用等问题进行了系统评述。总体来说... 详细信息

随着多道接收电感耦合等离子体质谱仪(MC-ICPMS)的发展和广泛应用,镉(Cd)稳定同位素已成为当前非传统同位素地球化学的研究热点之一。本文对Cd同位素的分析方法、组成特征、变化规律、分馏机制及环境应用等问题进行了系统评述。总体来说,地球样品的Cd同位素组成(δ114/110 Cd)分馏较小(-2.47‰^+3.17‰),陨石等地外物质同位素分馏较大(-9.07‰^+16.13‰),已发现的分馏过程包括蒸发/冷凝过程、吸附沉淀/溶解过程、生物吸收过程。同时,Cd同位素作为一种全新的地球化学指标,可指示物源、天体演化、海洋初级生产力及营养物质循环、全球碳循环等过程;有效示踪环境介质与生物体中Cd的污染来源,为环境科学的研究提供新的视角和信息。

关键词：镉同位素分馏地球化学环境示踪

1961-2020年华北地区7-8月份极端降水频次趋势转折及可能原因分析

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中国海洋大学学报（自然科学版） 2024年第1期54卷 12-25页

作者：郭敬环刁一娜邵建红刘逸璋中国海洋大学海洋与大气学院海洋气象学系山东青岛266100

区域性极端降水(Regional extreme precipitation,REP)破坏性强,会造成地质灾害和经济损失。本文利用逐日降水资料,研究了1961-2020年华北地区7-8月份REP频次趋势转折,并探讨其变化的可能原因。结果表明,华北地区7-8月REP天数存在1986、... 详细信息

区域性极端降水(Regional extreme precipitation,REP)破坏性强,会造成地质灾害和经济损失。本文利用逐日降水资料,研究了1961-2020年华北地区7-8月份REP频次趋势转折,并探讨其变化的可能原因。结果表明,华北地区7-8月REP天数存在1986、1995和2003年三个趋势突变点,在1961-1985年(P1)和1995-2002年(P3)时段有减少趋势,1986-1994年(P2)和2003-2020年(P4)时段呈现增多趋势。华北地区REP事件发生时有水汽通量辐合,并且中国东北部至朝鲜半岛对流层高层有异常高压(东北高压)存在。P2、P4时期较P1、P3时期东北高压位置偏南,38°N以南的华北地区水汽通量辐合增强,REP天数增多。P1、P2时期异常水汽通量来自印度洋和西北太平洋,而后两个时期只来自西北太平洋,这是东亚夏季风减弱、西太平洋副热带高压(西太副高)增强的结果。东北高压的发展在P1、P3时期与沿中纬度西风急流(急流)传输的波活动通量有关,在P2、P4时期高纬度活动中心发挥作用并且在季节背景上该高压较强,P2时期促使东北高压发展的波活动通量来自急流和高纬度活动中心两支路径,而P4时期波活动通量主要沿高纬度传播。REP天数减少在P1时期主要是东亚夏季风显著减弱不利于水汽向华北地区输送的结果,而P3时期是东亚夏季风减小和急流减弱共同作用所导致的;REP天数增多在P2时期是因为急流的显著增强,有利于东北高压的发展,而在P4时期西太副高的增强保证了东亚夏季风减弱之后向华北地区的水汽输送,并且北极海冰范围减少可能通过影响高纬度活动中心,在急流减弱之后建立了由高纬度向华北地区传输的波活动通量新路径,两者共同作用使得REP天数增多。

关键词：华北地区区域性极端降水趋势转折波活动通量

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