郑汴路路旁土壤-小麦系统重金属积累及其健康风险评价

按离路基不同距离采集土壤、麦苗和籽粒样品, 在测定样品重金属 (Pb、Cd、Zn、Cr和Cu) 的基础上, 开展了路旁土壤-小麦系统重金属分布、积累和污染状况分析, 并对膳食小麦 (Triticumaestivum) 引起的健康风险进行了评价。结果表明:1) 土壤-小麦系统重金属含量随着离开路基距离的增加呈先增加后减少的趋势, 土壤重金属含量>麦苗重金属含量>籽粒重金属含量。2) 麦苗和小麦籽粒对土壤重金属富集能力的大小顺序均为Cu>Cd>Zn>Pb>Cr, 麦苗对重金属的富集能力大于小麦籽粒。3) 膳食小麦所致的Cd个人健康风险较大。     

超富集植物遏蓝菜对重金属吸收、运输和累积的机制

遏蓝菜Thlaspi caerulescens可以在其地上部累积大量重金属如锌、镉等,是公认的超富集植物。由于该植物生物量小,不宜直接用于重金属污染的土壤植物修复,而被广泛作为一种模式植物来进行重金属富集机制研究。遏蓝菜对重金属离子的累积大致经过螯合剂解毒、地上部长距离运输以及在液泡中的储存等生理过程。已经发现的植物体内的金属螯合剂——有机酸、氨基酸、植物络合素(PCs)、金属硫蛋白(MT)和尼克烟酰胺NA等,区室化以及长距离运输相关的转运蛋白——ZIP(ZRT/IRTlike protein)、CDF(Cation diffusion facilitator)、Nramp(Natural resistance and macrophage protein)和HMA(Heavy metal ATPase)等家族,以上各种基因、多肽与蛋白等共同参与了植物对金属累积与耐受过程并发挥各自重要的作用。以下主要介绍了遏蓝菜重金属超富集相关的基因、多肽和蛋白,以及它们在重金属螯合作用和运输过程中的功能。     

桂北典型锰矿区周边土壤重金属污染状况及主要植物富集特征

为探究桂北某典型锰矿尾库区周边土壤和农作物重金属污染状况,筛选适合该地区污染土壤修复的植物材料,该研究在矿区周边采集了9种农作物和23种主要植物及其根际土壤,并测定了Cd、Mn、Cr、Pb和Zn 5种重金属含量,采用单因子污染指数法和综合污染指数法评价了矿区农田土壤、农作物中重金属的生态风险,通过计算植物对重金属的富集和转运系数评估其应用潜力。结果表明:(1)研究区土壤Cd、Mn污染最为严重,单因子污染指数分别为18.53、147.09,达到重度污染级别。(2)研究区花生和小白菜等作物可食用部位中的Cd、Cr、Pb含量均超过食品国家安全标准(GB 2762—2017)中的阈值,具有较高健康风险。(3)23种主要植物中青葙、鬼针草、一点红、蜈蚣草等对多种重金属转运系数大于1,具备富集型植物特征; 一把伞南星、蓖麻、千里光等根部重金属含量较高,转运系数较低,具备根部囤积型植物特征; 响铃豆、筒轴茅、苣荬菜等富集的重金属含量相对较低,且在重金属污染土壤中能健康生长,具备规避型植物特征。该研究结果表明,研究区土壤存在较严重的Cd/Mn复合污染,青葙等植物用于修复该复合污染土壤极具应用潜力。     

某农药工业园区周边土壤重金属含量与风险评价

以苏南某农药工业园区周边30km2区域为研究区,采用同心圆法采集土壤样品183个,分析了农药工业园区周边土壤Cd、Cr、Cu、Ni、Pb、Zn、Hg和As8种重金属含量、空间变异性、来源及潜在风险.结果表明:以自然背景值为评价标准,研究区表层土壤Hg、Cu、Cd和Pb平均含量超过自然背景值,其中Hg和Cu含量最高;以国标二级标准为评价标准,土壤Cd、Cr、Ni、Pb、Zn、As6种重金属的单项污染指数平均值均小于1,Hg和Cu分别为1.59和1.05.在农药工业园区周边土壤重金属污染较重的东南方向和西北方向,随着与园区距离的增加,土壤Cd、Ni、Pb、Cr、As、Hg、Zn和Cu含量先上升、后下降、再趋于平稳.通过分析农药工业园区周边土壤重金属综合污染指数发现,距离园区约200～1000m周边土壤污染的风险较大,而1000m以外逐渐达到安全范围.利用地统计学和GIS相结合进行分析发现,8种重金属污染指数有明显的空间变异.依据相关分析与主成分分析结果推测,Zn、Ni、Cr、Pb和As主要来源于成土母质,而Hg、Cu和Cd主要与人类活动有关.     

植物对铅的吸收、转运、累积和解毒机制研究进展

揭示植物对铅的吸收、转运、累积和解毒的分子机制,可以明晰农作物吸收铅的关键过程,阻控铅在粮食、蔬菜中的积累,降低重金属的食用风险;也可以阐明某些铅超积累植物的耐性与解毒机制,分离并克隆铅超积累的功能基因,培育高效的铅污染土壤修复植物.本文从铅进入植物的两个重要途径(叶片的吸附与吸收以及根系的吸收与转运)出发,系统总结讨论了植物对铅的吸收、转运、累积和分布的研究进展;采用胞外至胞内的空间顺序,分别从植物根系分泌物的解毒、细胞壁的固定和动态响应、细胞质膜的选择透过性作用、液泡的区隔化作用以及金属有机配体的螯合等方面论述植物铅耐性和解毒的分子机理,并在此基础上提出存在的问题和今后研究的重点.     

西北内陆盐湖盆地土壤重金属Cr、Hg、As空间分布特征及潜在生态风险评价

选取位于西北内陆的吉兰泰盐湖盆地为研究对象,按照表层(0—10 cm)、50 cm层(50—60 cm)和100 cm层(100—110 cm)分层土壤取样,系统采集了120个样品,测定了重金属Cr、Hg和As,以及主要化学成分的含量,以地统计学插值绘图揭示了吉兰泰盐湖盆地Cr、Hg和As的空间分布特征,以单因子指数法、内梅罗指数法和潜在生态风险指数法评价解析了盐湖盆地Cr、Hg和As的污染及生态风险状况,以统计相关检验和主成分分析法进行了盐湖盆地Cr、Hg和As的源分析。结果表明:1)盐湖盆地土壤中Cr、Hg、As总体具有相似的空间分布特征,Cr在西北部的巴音乌拉山、乌兰布和沙漠地区和西南台地地区的含量较高,Hg仅在西南低山台地地区、以及东北局部区域的含量较高,As在盐湖附近、东南贺兰山、巴音乌拉山西北部和乌兰布和沙漠地区含量较高;2)基于内蒙古土壤质量背景值,土壤污染分布次序为AsHgCr,其中Hg和As中度污染以上累计比重达到为45%,而Cr仅有7.5%的轻微污染;研究区无清洁土壤,仅有尚清洁土壤占2.5%,开始受到污染和中度污染以上土壤比重为50%和42.5%;土壤潜在风险次序为HgAsCr,Hg整体处于很强生态风险水平;轻微生态风险占到40%,由中度、强度到极强在20%以内,很强生态风险程度略超20%,大部地区处于轻微生态风险状况;3)基于国家土壤环境质量二级标准值,土壤中Cr、Hg、As无论是单因子污染、综合污染,还是潜在生态风险指数均未出现超标区域,不存在Cr、Hg、As污染或潜在生态风险,但相对内蒙古整个地区来说,盐湖盆地Cr、Hg、As含量较高;4)研究区土壤中Cr主要来源于土壤母质形成过程中的自然来源,Hg和As主要来源于工业排放、交通污染源等人类活动,均受到人类活动和自然环境变化的综合影响。     

入侵植物假苍耳对土壤中铜、铅重金属污染的富集特征

通过室内盆栽试验研究入侵植物假苍耳(Iva xanthifolia)在营养生长阶段对铜、铅的耐性及富集特征。实验结果表明,在1~16 mg·L^-1的添加铜处理及0.5~14 mg·L^-1的添加铅处理条件下,假苍耳对铜、铅两种单一金属均有很强的耐性及富集作用,重金属在植物体地上部和地下部的富集量分别为607.59、137.20,404.38、34.53 mg·kg^-1,对应的富集系数为11.39、4.18,转运系数4.43、11.71,且重金属在植物体内的分布规律均表现为：茎部＞叶片＞根部,地上部分的积累量远大于地下部分。对叶色、株高及生物量等特征的观察表明假苍耳的生长未受到抑制,符合超富集植物的基本特征。与一般超富集植物相比,假苍耳作为一种外来入侵植物,具有生长迅速、植物材料易得,生物量大且分布范围广的优点。     

商品大米中Cd、Pb、Cr的污染状况及健康风险评价

为了解本地商品大米中重金属的污染情况,采用微波消解法和电感耦合等离子体原子发射光谱(ICP-AES)法,对144个大米样品进行Cd、Pb和Cr含量的检测,采用单项污染指数和内梅罗综合指数法对其污染状况和健康风险进行分析评价。结果表明,样品中Cd、Pb和Cr的超标率分别为0.69%、27.78%和34.03%。无等级大米中3种重金属的超标率高于有等级大米,但差异不显著。本土商品大米样品中Cd的含量显著高于外省样品,Pb含量差异不显著,Cr的含量显著低于外省样品。144个样品中处于安全级别的样品仅占63.89%。健康风险评价结果显示,当地居民通过食用大米实际摄入Cd和Pb的量都低于FAO/WHO推荐的每人每日的允许摄入量,不存在严重的健康风险,但却存在Cr的健康风险问题。     

曼陀罗和苍耳对污染土壤中镉的吸收与富集

目的:研究曼陀罗和苍耳对重金属镉的吸收与富集特征.方法:室外盆栽试验和室内原子吸收测定曼陀罗和苍耳体内的镉含量.结果:土壤中的镉刺激了植物的生长,曼陀罗和苍耳的生物量都比对照有所增加;曼陀罗和苍耳体内的镉含量随土壤中镉浓度的增加而增加;当土壤中镉浓度为100mg·kg-1时,曼陀罗地上部分富集系数为1.15,大于1,而在其它测试浓度下均小于1;苍耳地上部分的富集系数在所有测试浓度下都小于1.结论:曼陀罗和苍耳都不属于镉的超富集植物.     

河口潮间带沉积物重金属累积及生态风险评价

于2015年7月份在闽江口鳝鱼滩湿地布设两条样带(T1和T2),并分别选取5个采样点采集沉积物样品。因重金属Co和V对动物和人类会造成一定危害,且闽江河口潮间带Co和V的研究较少,则对其理化性质、Co和V的空间分布特征以及污染程度等进行了研究,旨在为Co和V的污染研究提供参考。结果显示,该沉积物中Co和V的平均浓度分别为15.19 mg/kg、102.94 mg/kg,均高于福建省背景浓度,与其他河口对比,Co和V浓度处于中等水平。Co和V的含量由陆向海方向略有下降。地累积指数法分析得出沉积物中Co含量呈现轻度污染状态,V呈现无污染状态。此外,Co和V的潜在生态危害系数E_rⁱ分别为7.24—14.85和1.47—4.17,表明潜在生态危害轻微,闽江河口潮间带沉积物中Co和V属于轻度污染。     

Human health risk assessment of heavy metals in the soil–Panax notoginseng system in Yunnan province,China

In this study, a total of 69 topsoil samples and 10 Panax notoginseng samples from Yunnan Province were collected and the concentrations of As, Cd, Cu, Hg, Ni, Pb and Zn in all the samples were determined. The hazard index (HI), total carcinogenic risk (TCR) and estimated daily intake (EDI) of heavy metals were calculated to assess the health risk of P. notoginseng growers and consumers. The average concentrations of As, Cd, Cu, Hg, Ni, Pb and Zn in P. notoginseng planting soils are 43.6, 0.55, 50.8, 0.30, 73.4, 58.2, and 161 mg/kg, respectively. The average Nemerow integrated pollution index of heavy metals in soils is 1.8, indicating that the P. notoginseng planting soils are slightly polluted by those heavy metals. The average HI value is 1.29 and the TCR value of As is above the threshold value, suggesting that As pollution in soil has adverse impact on local growers' health. P. notoginseng is polluted by Cd, As and Pb. 39.1% of estimated daily intakes of As for P. notoginseng consumers through leaf consumption exceeding its permitted daily exposure dosages, suggesting that there is a potential health risk for P. notoginseng consumers to consume P. notoginseng leaves.     

Bioaccessibility of Cd,Cr, Cu,Mn, Ni,Pb, and Zn in Mediterranean mussel (Mytilus galloprovincialis Lamarck, 1819) along the southeastern Black Sea coast

The adverse effect of seafood consumption on human health is related to the bioaccessibility in contrast with the total heavy metal level in the tissues. In this study, bioaccessibility of Cd, Cr, Cu, Mn, Ni, Pb, and Zn in Mediterranean mussel (Mytilus galloprovincialis Lamarck, 1819) edible soft tissues collected along the southern Black Sea coast were investigated using in vitro digestion model. Total Pb concentration in the tissues was found to be higher than the maximum permissible limits set by European Commission. The bioaccessibility of metals in the tissues was found to be decreased in the order: Ni (83.11%) > Cu (80.47%) > Zn (76.86%) > Cd (73.32%) > Mn (69.11%) > Pb (61.07%) > Cr (58.44%). While significant positive linear regression was observed between total and bioaccessible concentrations for Mn, Pb, and Ni, significant negative linear regression was found for Cd (p < .05). The hazard quotients (HQ) calculated using bioaccessible amount were detected lower than the limit (HQ <1), which may not pose a potential hazard to humans reported by US Environmental Protection Agency. In sum, mussel consumption from sampling sites may cause a potential risk concerning human health especially for Cd and Pb in case of increased portion sizes.     

湘南某矿区蔬菜中Pb、Cd污染状况及健康风险评估

通过采集湘南某矿区周边农田中种植的蔬菜和对应耕作层土壤样品,探究了农田蔬菜Pb、Cd的污染状况,蔬菜和土壤重金属含量之间的相关性,蔬菜中重金属对人体的健康风险。结果表明:(1)污染区土壤重金属污染非常严重,叶菜类蔬菜重金属超出了食品卫生标准限值,但是果菜类蔬菜中重金属没有超出食品卫生标准限值。(2)不同蔬菜不同器官所含Pb、Cd有明显差异;不同种类蔬菜Pb、Cd含量不同,一般是叶菜类果菜类;同种蔬菜不同部位重金属含量的顺序也不同,一般为根茎叶果,或根叶茎果。(3)二类蔬菜中重金属Pb、Cd的富集系数顺序为叶菜类果菜类。(4)蔬菜中Pb、Cd含量与土壤中相对应元素含量均无显著相关性。(5)就农产品安全性而言,果菜类蔬菜比叶菜类蔬菜更适合在此矿区栽培。     

Pollution and health risk assessment of heavy metals in urban soil in China

The pollution and potential health risk due to lifetime exposure to heavy metals in urban soil of China were evaluated, based on the urban soil samples collected from published papers from 2005 to 2014. The contamination levels were in the order of Cd > Hg > Cu > Zn > Pb >As > Ni > Cr, and Hg and Cd fell into the category of “moderately contaminated” to “heavily contaminated.” The non-carcinogenic risk for different populations varied greatly, among which children faced high risk, and then the adult female and adult male followed. The hazard index (non-carcinogenic risk) higher than 1.00 occurred in Shanghai, Gansu, Qinghai, Hunan, and Anhui, whereas most of those in northern and western China had low risks. For the carcinogenic risk, Anhui and Ningxia provinces had urban soils exceeding the safe reference (1 × 10^?6–1 × 10^?4). Qinghai and Gansu had high carcinogenic risks since their risk indexes were much closer to the reference, and the others were in low risk.     

Heavy metal accumulation in frogs surrounding an e-waste dump site and human health risk assessment

Abstract

This study was performed heavy metals (As, Cd, Cr, and Pb) in water, soil and frogs around an electronic-waste dump site. The bioaccumulation factors (BAFs) of heavy metals in three frog species and potential human health risks were assessed. Heavy metals were analyzed using inductively coupled plasma-optical emission spectrometry. The Cd and Pb concentrations in water samples and As and Pb concentrations in soil samples from within the e-waste dump site exceeded the standards. The heavy metal concentrations in the muscles of three frog species were as follows: Cr?>?Pb?>?As?>?Cd, and there were no significant differences among frog species except in the case of Pb (p?<?0.05). Only the Cr concentrations exceeded the food quality standards. The relative order of the BAFs for heavy metals in frogs as a result of uptake from the water and soil was Cr?>?As?>?Pb?>?Cd and Cr?>?As?>?Cd?>?Pb, respectively, which indicated that the uptake from water was greater than that from the soil. The assessment of the health risk index and carcinogenic risk (CR) indicated potential human health effects from As, Cr, and Pb via the consumption of frogs.     

Distribution and health risk assessment of heavy metals in soil surrounding a lead and zinc smelting plant in Zanjan,Iran

One of the problematic issues in soil pollution studies is heavy metal particles which are produced by mines and smelting units and spread through wind action and/or runoff. Pollution and health risk assessment of cadmium, lead, zinc, copper, and nickel in soil around the lead and zinc smelting factory was carried out in Zanjan City, Iran. Contamination factor (Cf), pollution load index (PLI), geoaccumulation index (Igeo), hazard quotient (HQ), hazard index (HI), and carcinogenic risk were pollution and human health risk assessment metrics in this study. Based on the Iranian soil guideline value, soil samples in the studied areas were contaminated the least by copper and nickel and the most by cadmium. PLI results showed that soils near the production line were heavily or extremely heavily polluted. The results of Cf and Igeo showed that lead and zinc were the most important contaminants. Health risk assessment indicated that lead and cadmium in soil were the main contaminants, which pose both carcinogenic and non-carcinogenic risks to human health; carcinogenic risk levels were unacceptably high (above 1 × 10^?4). It can be concluded that mining and smelting activities degrade soil quality in this region and the soil pollution might be extended to farming areas.     

Source apportionment and health risk assessment of heavy metals in agricultural soils in Xinglonggang,Northeastern China

Heavy metals in soil can affect human health through the exposure pathways of oral ingestion, dermal contact, and inhalation. In this study, to assess the health risk of heavy metals in the agricultural area of Xinglonggang, 52 soil samples were collected and tested to obtain the concentrations of As, Cd, Cr, Cu, Ni, Pb, V, and Zn in the soil. The enrichment factor indicated that the heavy metals of the agricultural soils were enriched, but the degree of enrichment was mild for all of the heavy metals. Coefficient analysis and principal component analysis indicated that V, Cr, Ni, and Pb were mainly from natural sources, As was from irrigation, Cu and Cd tended to be from chemical fertilizers and pesticides, and Zn was from mixed sources including irrigation, chemical fertilizers, and pesticides. A human-health risk assessment indicated that the residents in the study area face high risk from carcinogens and low risk from noncarcinogens; As and Cr are the major heavy metals affecting human health. This study provides a reference and a basis for formulating effective measures to prevent and control heavy metal enrichment in agricultural soils.     

Distribution of heavy metals in soils and vegetables and health risk assessment in the vicinity of three contaminated sites in Guangdong Province,China

Due to rapid industrialization and urbanization, human activities like industrial and agricultural production, transportation, aggravate heavy metal pollution in soil and continue to endanger vegetables and human health. In this study, three contaminated areas affected by heavy metal pollution in Guangdong Province were investigated in terms of Cu, Zn, Pb, and Cd concentrations in soil and vegetables. Further analyses of the contamination status and potential risks to the health of residents consuming these vegetables were conducted. Results showed the following average heavy metal concentrations in vegetables and soil: Shaoguan > Guangzhou > Dongguan, indicating that mining has caused massive soil-heavy metal pollution. The heavy metal concentrations and Bioconcentration factors (BCFs) showed the following trend: leaf-vegetables > fruit-vegetables > root-vegetables, and those of vegetable type were as follows: Cd > Zn > Cu > Pb. The Nemero pollution index (PI) of all research region soils and hazard index (HI) exceeded 1. Hence, more attention should be paid to the potential for adverse health effects caused by the consumption of vegetables produced in these sites . Thus, effective measures are encouraged, with a focus on children due to their vulnerability to these heavy metals.     

The accumulation characteristics and potential health risks of heavy metals in vegetables from reclaimed area of China

The reclamation of subsidence area was regarded as a useful pathway to rebuild landscape and ecosystem. However, the elevated concentrations of heavy metals in the reclaimed area may lead to potential environmental and health risks. This study was aimed at investigating the accumulation of heavy metals in the soils and vegetables, and evaluate the potential health risks to human beings via consuming these vegetables. The concentrations of heavy metals (Cd, Cu, Pb, and Zn) were measured by using inductively coupled plasma mass spectrometry. The elevated concentrations of heavy metals were found in the soil from the reclaimed area when compared with the background value. The concentrations of heavy metals were various among the different vegetable species. The heavy metal tolerance could be found in all the selected vegetables. The elevated concentrations of Cu, Pb, and Zn in the edible part of the selected vegetables indicated that the consumption of these vegetables may lead to potential health risk. The intake of soybean, radish, sweet potato, and mugwort may lead to potential health risks due to the elevated target health quotients. Chinese cabbage and pepper were regarded as the suitable vegetables which may help in reducing the potential health risk.     

Assessment of Cu,Pb and Zn content in selected species of grasses and in the soil of the roadside embankment

It was assumed in the study that heavy metals occurring in soils and the air accumulate in grasses constituting the main species used in the turfing of soil in road verges and embankments along traffic routes and in other parts of urbanized areas. The aim of the present study was to assess the bioaccumulation of Cu, Pb, and Zn in three selected lawn cultivars of five grass species and in the soil of the roadside green belt in terms of soil properties and heavy metal uptake by plants in the aspect of determining their usefulness in protecting the soils from contamination caused by motor vehicle traffic. Samples of the plant material and soil were collected for chemical analysis in the autumn of 2018 (October) on the embankment along National Road No. 17 between Piaski and ?opiennik (Poland), where 15 lawn cultivars of five grass species had been sown 2 years earlier. During the study, Cu, Pb, and Zn levels were determined in the aboveground biomass of the grasses under study and in the soil beneath these grasses (the 0–20 cm layer). All the grass species under study can thus be regarded as accumulators of Cu and Zn because the levels of these elements in the aboveground biomass of the grasses were higher than in the soil beneath these grasses. The present study demonstrates that the grasses can accumulate a large amount of Cu and Zn from soils and transfer it to the aboveground biomass. Tested species of grasses are not a higher bioaccumulators for Pb. The best grass species for the sowing of roadsides embankment, with the highest BCF values for the studied metals, is Lolium perenne (Taya variety).