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861.
露天存放的铅锌尾矿受到自身酸化和酸雨的双重影响,从而加剧尾矿对环境的影响。因此,研究尾矿在酸性条件下的重金属行为及其植物毒性,对植物在铅锌尾矿地的自然定居有非常重要的意义。将铅锌尾矿砂装柱,用pH2~7溶液淋溶50天的结果表明,酸度的提高可以显著地增加尾矿砂中重金属(Pb、Zn、Cu和Cd)的溶出。而随着时间的延长,Zn的溶出量明显增高,Pb和Cu的溶出则逐渐降低。在pH值<3时,Cd的溶出逐渐升高,pH值>3时,Cd的溶出也呈下降趋势。酸度对重金属溶出的影响由大至小依次为Zn>Cd>Cu>Pb。渗滤液对植物的毒性随着起始淋溶酸度的提高与时间的推移而加剧 相似文献
862.
The effects of age on cadmium concentrations was investigated in Cory's shearwater, Calonectris diomedea, Lesser black-backed gull, Larus fuscus, and great skuas, Catharacta skua. There was no evidence for the continued accumulation of cadmium with increasing adult age. Adult shearwaters did have higher concentrations of cadmium compared to young fledglings, but there was no significant difference between cadmium concentrations in adult and sub-adult gulls. In addition, the sample of great skuas were of known age (3–22 yrs old) and showed no evidence of increasing cadmium concentrations with adult age in liver or kidney. However, it is possible that age accumulation of cadmium in great skuas was masked by individual dietary preferences overriding the effects of increasing age. It is often assumed that cadmium concentrations continue to accumulate with increasing adult age, but seabirds may have evolved some as yet unknown mechanism for excretion or more rapid turnover of cadmium than previously thought. The implications of this for the use of seabirds as biomonitors is discussed. 相似文献
863.
Due to papulation increase in Pakistan the demand of drinking water increased day by day. After the industrial grooming the wastewater producing harmful effect on the surrounding area of industries and drinking water contamination increased. Pakistan is on 82 amongst the 125 countries of the word having drinking water problem. Different parameter set by World Health Organization (WHO) and Pakistan Environmental Protection Agency (Pak-EPA) of hazard dimension index (HD) and Lifetime Cancerogenic risk Calculation (LFCR) of Potentially toxic metals that are As, Cd, Cr, Ni, Pb (PTMs) are higher, and the school age children are under high risk of cancer. All the drinking constraints set by regulating authority is fully neglected by inopportune human process by solid waste dumping and houses and industrial disposal with any proper treatment. This study discusses all the HD and LFCR parameter in three age group children, male and female through drinking water around the Hattar Industrial Estate (HIE) in Pakistan. In children and women more HD and LFCR thread than the adult man. The overall result shows that the HD risk is higher than the LFCR due to the PTMs in drinking water only HD is exceed from the limit of WHO and Pak-EPA. If there is no proper arrangement take place for the removal of As and PTMs from the industrial wastewater and drinking water than within few years all the population around the study area effected with different type of cancer. 相似文献
864.
Jerzy Falandysz 《Journal of environmental science and health. Part. B》2018,53(8):546-560
Leccinum scabrum is an edible mushroom common in European regions in the northern hemisphere. Macro and trace mineral constituents such as Ag, Al, Ba, Ca, Cd, Co, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, P, Rb, Sr and Zn were studied in L. scabrum and in the top soil collected from the same location underneath soil substratum. The “pseudo-total” and labile (extractable fraction of minerals) were measured to get insight into the levels, distribution between the morphological parts of fruiting bodies, potential for their bioconcentration by mushroom and evaluated for human exposure via consumption of the mushroom. The sampling sites include the Dar?lubska Wilderness, Trójmiejski Landscape Park, Sobieszewo Island, Wdzydze Landscape Park and outskirts of the K?trzyn town in Mazury from the norther part of Poland. Median values of K, Rb and P concentrations in dehydrated L. scabrum were for caps in range 27,000–44,000 mg kg?1, 90–320 mg kg?1 and 6,200–9,100 mg kg?1, and followed by Mg at 880–1,000 mg kg?1, Ca at 48–210 mg kg?1 and Al at 15–120 mg kg?1. The median concentrations of Cu, Fe, Mn and Zn in caps were in range 15–27 mg kg?1 db 38–140 mg kg?1, 5.3–27 mg kg?1 and 130–270 mg kg?1. For Ba and Sr, concentrations on the average were at ~1 mg kg?1, and almost equally distributed between the caps and stipes of the fruiting bodies. L. scabrum mushrooms were low in toxic Ag, Cd, Hg and Pb, for which the median values in dried caps from five locations were, respectively, in range 0.48–0.98 mg kg?1 (cap to stipe index, QC/S, was 2.5–4.1), 1.0–5.8 mg kg?1 (QC/S 2.9–3.8), 0.36–0.59 mg kg?1 (QC/S 1.6–2.7) and 0.20–0.91 mg kg?1 (QC/S 1.2–1.9). Substantial variations in the concentrations of the “pseudo-total” fraction (extracted by aqua regia) or labile fraction (extracted by 20% solution of nitric acid) of the elements determined in forest topsoils were noted between some of the locations examined. The elements K, P, Cd, Cu, Hg, Mn, Na, Rb and Zn can be considered as those which were bioconcentrated by L. scabrum in fruiting bodies, while the rates of accumulation varied with the sampling location. 相似文献
865.
西宁市非采暖季和采暖季PM2.5中14种金属元素特征 总被引:1,自引:0,他引:1
于2012年11月采暖季和2013年9月非采暖季,在青藏高原典型城市西宁市4个采样点采集细颗粒物(PM_(2.5))样品,共获得40个有效样品。用微波消解-ICP-MS法、原子荧光法分析了样品中14种重点防控金属。结果表明:14种重点防控金属中Ag、Tl平均质量浓度为0.10~0.50 ng/m~3,Co、Sb、Hg平均质量浓度为0.50~4.00 ng/m~3,V、Cd、Cr、Ni、Cu、As平均质量浓度为4.00~50.0 ng/m~3,Mn、Pb、Zn平均质量浓度为50.0~2 000 ng/m~3。采样期间,采暖季相比非采暖季,PM_(2.5)质量浓度有下降趋势,不同采样区金属元素浓度有增有减。富集因子分析结果表明,重点防控金属元素在非采暖季主要来源于土壤风沙扬尘、机动车尾气和工业排放,采暖季主要来源于土壤风沙扬尘、燃煤、燃油、机动车尾气和工业排放。非采暖季Zn、Ag、Cd、Hg、Tl和Pb富集因子较高,采暖季Zn、As、Ag、Cd、Sb、Hg、Tl、Pb富集因子较高,更容易受到人为源的影响。 相似文献
866.
867.
以某高校新生发样为研究样本,将生源地分为东北、西北、西南、华北、华南、华中、华东7个地域,采用电感耦合等离子发射光谱法对发样中所含铬、铜、镍、铅、锌进行测定,通过非参数检验及偏相关性检验分析不同地区发样中重金属含量与性别、身体质量指数(BMI)的关系。结果显示,所采集发样中铬、铜、镍、铅、锌的含量变化范围依次为0.22~101.84、0.36~112.24、0.70~128.75、1.39~136.13、1.12~719.50μg/g;发样中重金属浓度的地区排序为东北>华东>华北>西北>华中>西南>华南。聚类分析和主成分分析结果显示,不同地区发样中重金属的来源有所差异:东北、西北、华北地区发样中重金属可能主要来源于燃煤、工业生产过程、机动车排放,方差贡献率分别为39.47%、25.78%、22.89%;华中、华东、西南、华南地区发样中重金属可能主要来源于工业生产过程、机动车排放、冶金化工过程,贡献率分别为47.76%、27.51%、18.24%。相关性检验显示,男性发样内铬、铜、镍、铅含量高于女性。其中,偏胖或偏瘦女性存在较高的铅暴露风险;40.2%的男性发锌含量低于正常值下限,24.4%的女性发锌含量低于正常值下限,且偏瘦女性发内缺锌现象显著;男、女发铜含量高于正常值上限的比例分别为91.8%、85.6%,存在不同程度的铜暴露风险。 相似文献
868.
869.
870.
长沙市夏季大气颗粒物中重金属的形态及其源解析 总被引:1,自引:0,他引:1
对长沙市高开区、经开区、开福区以及马坡岭4个采样点夏季的大气颗粒物(TSP)浓度以及颗粒物中的重金属元素Cu、Zn、Mn、Pb和Cd的浓度和形态分布进行了研究分析,利用污染因子(Cf)对重金属元素的可保持能力进行了评价,并利用因子分析方法(PCA)分析TSP中重金属元素的主要来源。结果显示长沙市夏季TSP平均浓度为220.7μg/m3,表明长沙市颗粒物污染较严重。TSP中重金属元素浓度大小顺序为:ZnPbCuMnCd。从形态分布来看,大约63.3%~89.0%的Cu主要存在于可氧化态(F3),而Mn在这一态中分布最少。元素Zn、Cd则主要分布在弱酸提取态,分别占了70%和35%。Pb主要分布在残渣态,大约为24%~43%。由污染因子计算可知Cu、Cd和Zn比Mn、Pb有更高的迁移性。 相似文献