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研究贵州喀斯特高地质背景对农产品中F、Cd含量水平的影响,评价农产品F、Cd暴露对不同人群的健康风险。以7个市州为研究区域,采集255个样品(110个水稻、130个玉米、15个马铃薯),分别采用氟离子选择电极法及电感耦合等离子体质谱(ICP-MS)测定样品中F、Cd含量。参照靶标危害系数(THQ)和危害系数(HI)对儿童及成人的健康风险进行评价。结果表明,大米、玉米及马铃薯中Cd含量为0.003~0.629、0.000~0.556、0.016~0.153 mg/kg;F含量分别在0.130~1.970、0.357~4.717、0.557~1.058 mg/kg之间。大米、玉米及马铃薯分别有19.09%、23.08%、26.70%的样品Cd含量超过阈值(0.2、0.1、0.1 mg/kg,GB2762-2017)。大米中氟镉含量呈正相关(r=0.376,p<0.01),玉米中呈负相关(r=-0.391,p<0.01)。不同作物的THQ和HI显示,儿童和成人摄食大米的风险大于玉米和马铃薯。儿童及成人摄食大米后THQCd、THQF、HI分别为:0.965、 0.073、0.970;0.799、0.060、0.859,儿童及成人摄食玉米后THQCd、THQF、HI分别为:0.430、0.185、0.422;0.121、0.052、0.173,儿童及成人摄食马铃薯后THQCd、THQF、HI分别为:0.020、0.069、0.024;0.008、0.019、0.028。研究结果表明贵州省农产品受不同程度氟镉污染,食用当地生产的农作物具有潜在的健康风险,且儿童风险大于成人。 相似文献
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Qinghai Guo Yin Zhang Yaowu Cao Yanxin Wang Weide Yan 《Environmental science and pollution research international》2013,20(11):8210-8219
Hydrotalcite and its calcination product were used to treat pure water spiked with various concentrations of boron and geothermal water containing boron as a major undesirable element. The kinetics process of boron sorption by uncalcined hydrotalcite is controlled by the diffusion of boron from bulk solution to sorbent-solution boundary film and its exchange with interlayer chloride of hydrotalcite, whereas the removal rate of boron by calcined hydrotalcite rests with the restoration process of its layered structure. The results of isotherm sorption experiments reveal that calcined hydrotalcite generally has much stronger ability to lower solution boron concentration than uncalcined hydrotalcite. The combination of adsorption of boron on the residue of MgO–Al2O3 solid solution and intercalation of boron into the reconstructed hydrotalcite structure due to “structural memory effect” is the basic mechanism based on which the greater boron removal by calcined hydrotalcite was achieved. As 15 geothermal water samples were used to test the deboronation ability of calcined hydrotalcite at 65 °C, much lower boron removal efficiencies were observed. The competitive sorption of the other anions in geothermal water, such as HCO3 ?, SO4 2?, and F?, is the reason why calcined hydrotalcite could not remove boron from geothermal water as effectively as from pure boron solution. However, boron removal percents ranging from 89.3 to 99.0 % could be obtained if 50 times of sorbent were added to the geothermal water samples. Calcined hydrotalcite is a good candidate for deboronation of geothermal water. 相似文献
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我国5种重金属类有毒空气污染物(Pb,Hg,Cd,Cr,As及其化合物)排放量大,不仅严重破坏生态环境,也极大威胁人体健康,亟待完善污染防治政策。本文分析了排放这5种重金属类有毒空气污染物的重点行业,然后基于行业分析结果,提出我国重金属类有毒空气污染物的优先控制政策,为相关管理部门决策提供参考。具体建议如下:第一,优先控制5种重金属类有毒空气污染物;第二,制定重金属类有毒空气污染物排放标准;第三,放源分类管理;第四,多污染物协同控制;第五,提升监管能力;第六,加强宣传教育,鼓励公众监督。 相似文献
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综述从活动断裂的研究和进展出发,通过追溯国内外活动断裂研究发展历史,结合当前城市活动断裂研究的理论与方法,认为地球物理的综合物探手段在城市活断层探测工作中将会越来越重要。文中重点介绍了城市活断层探测工作中所采用的地球物理方法的类型,以及在区域探查与初步鉴定阶段、详细探测与精确定位阶段、孕震构造探测阶段可能涉及到的各种地球物理探测方法、适用范围及所能解决的主要问题等。文章结合哈尔滨城市活断层探测项目实例,表明在面对岩石和地层的众多物性差异和勘查结果的多解性时,地球物理的综合物探方法在提高资料的反演和解译准确度方面具有十分重要的意义。 相似文献
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新型甲醛被动式检气管的研制 总被引:5,自引:0,他引:5
新研制的甲醛被动式检气管是建立在气体分子扩散和化学吸收原理基础上的,检气管内的惰性担体上浸渍了对甲醛特效的希夫试剂。当管内进入甲醛气体时,即发生显色反应,检气管的显色长度的平方与甲醛浓度及采样时间的乘积成线性关系。检出下限为0.015mg#L(采样5h),它集采样与分析为一体,结构简单,不需动力,便于携带和操作方便,应用于检测某厂刨花板车间和制胶车间的甲醛气体,与传统的注射器采样比色分析法对比,结 相似文献
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Long Yanqiu Li Qinghai Zhou Hui Meng Aihong Zhang Yanguo 《Journal of Material Cycles and Waste Management》2018,20(2):1026-1035
Journal of Material Cycles and Waste Management - Thermogravimetric analyzer was applied to analyze 22 solid materials and their mixtures at a heating rate of 10 K min−1... 相似文献