再生铅企业土壤-地下水中重金属污染迁移特征

为了解某再生铅企业厂区土壤和浅层地下水重金属污染状况,采集了96个土壤样品和4个地下水样品,定量分析了其Pb,Cd,As的含量及空间分布特征,探讨企业生产对环境造成的影响。结果表明,该区域土壤中Cd、As、Pb超标率分别为67.0%,35.1%,11.7%,在厂区呈现局部富集现象,最大值是土壤背景值的几十倍乃至数千倍;在垂直方向上由于Pb,Cd,As在土壤中迁移率较低,其值随深度增加呈总体下降趋势;该区域地下水中Pb,Cd,As值远低于地下水质量标准值。     

云南个旧土壤农作物重金属污染特征及潜在风险

在实地调查和实验室分析的基础上,对云南省个旧市大屯镇土壤农作物重金属污染状况进行了评价。结果显示:个旧市大屯镇调查区域土壤中Pb、Zn、Cd、As平均质量分数分别为943. 5、454. 8、3. 4、302. 1 mg/kg,分别为国家农用地土壤污染风险管控标准筛选值的7. 8、1. 8、11. 2、10. 1倍,土壤污染严重。土壤Cd的生态危害最强,As、Pb的生态危害次之,Zn表现为轻微的生态危害。从潜在生态危险指数来看,所采集的土壤样品皆表现为极强的生态危害。所采集农作物与食品安全国家标准对比,结果显示,大米中Pb、Cd和As的超标率分别为35%、55%和100%;玉米中Pb、Cd和As的超标率分别为13%、0%和0%;小苦菜Pb、Cd和As的超标率分别为100%、60%、100%;小米菜中Pb、Cd和As的超标率均为100%,蔬菜类的重金属超标情况相对于谷物类较为严重。研究区域土壤样品总量Pb、Zn与有效态皆呈极显著正相关关系,总量Cd与有效态呈弱正相关关系,总量As与有效态表现为相关性不显著。     

云南会泽者海镇典型矿区场地重金属污染特征及健康风险评价

选择云南会泽县者海镇矿区重金属污染场地,按不同暴露途径计算土壤中Pb、As、Cd、Zn、Cu、Cr、Hg等金属污染物的风险,并通过风险评价,分析场地内的健康风险水平。结果表明:所有暴露途径中Zn、Cu、Pb对人体健康的平均风险较小。在居住用地情景下,土壤中Cd的综合致癌风险为2. 6×10-5,As的综合致癌风险为3. 3×10-4,场地内As和Cd的污染对敏感受体健康的潜在危害较大。     

徐州城市表层土壤中重金属的富积、分布特征与环境风险

研究了徐州城市表层土壤的21个样品中30种元素的富集与分布特征。结果表明,与我国土壤元素的背景值(算术平均值)相比,表层土壤中Zn、Cd、As、Hg、Sb、Sn、Ag等元素富集大;Fe、Se、Sc、Ba、Bi、Pb、Cu、Ni、Cr、Mn、Mo、Be、Ti、Al、Ga、Li、Co等元素的富集较小。污染元素的空间分布特征显示了Zn、Cu、Pb、Cd等元素主要与交通运输等扩散污染源相关,而元素As、Sb的空间分布主要与工业污染源(点源)有关。环境风险指数的计算结果表明,表层土壤中重金属污染具有较大的环境风险,其中属于中等环境风险级别以上的样品占近40%,而且高风险区域主要集中在钢铁厂和化机厂等工业区范围内。     

昆明市湿地公园地表灰尘重金属污染特征及健康风险评价

城市湿地公园是人们休闲娱乐的重要场所，但其地表灰尘的人群暴露健康风险却鲜有报道。该研究收集昆明市3个最受欢迎的湿地公园景区地表灰尘样品，利用等离子发射光谱仪(ICP-OES)测定灰尘中Pb、Cd、Hg、As、Zn、Cr、Cu、Ni、Co、Mn含量，使用地累积指数法(I_geo)、污染负荷指数法(PLI)和潜在生态风险指数法(RI)探讨湿地公园灰尘重金属污染特征，借助美国环保署健康风险评价模型，开展成人和儿童的重金属健康风险评价。结果表明：灰尘中10种重金属平均含量均超昆明市土壤背景值，其中Cd、Hg和Zn平均含量超背景值6倍，Cr、Ni、Co的I_geo<1。污染负荷指数法结果显示Hg、Cd、Zn中度污染，Pb、Cu和As则具有中等以上生态风险。人体健康风险评价结果显示，经口摄入为重金属主要暴露途径，其次是皮肤直接接触和呼吸吸入。Ni、As、Cd、Co和Cr的致癌风险值均小于10^-6,但若长期处于此种环境，可能会存在潜在的致癌风险。对于非致癌元素而言，Pb、Zn、Cu、Mn非致癌健康风险值都远小于1,即风险可以忽略。     

典型铝塑厂周边土壤重金属分布特征与健康风险评价

为探究铝塑园区周边土壤重金属污染情况,选取山东省某城市塑料开发区为研究区,按照分层采样方式获取到80个土壤样品,分别测定土壤中As、Cd、Hg、Cr、Cu、Ni、Pb、Zn含量,运用统计分析法探讨土壤重金属等的分布特征和来源,并利用健康风险评价模型确定了土壤重金属对周边居民的健康风险。结果表明:As、Cd、Hg、Cr、Cu、Ni、Pb和Zn均超出山东省土壤背景值,其中Cd、Hg、Cu和Pb分别超出背景值48. 15%、106. 90%、62. 04%和39. 96%,表明土壤中存在一定程度的重金属积累,在周边140～210 m处最为严重,且受人类活动影响强烈,与风向关系不大;土壤重金属垂直分布特征大致呈现随着深度的增加不断增加,在20 cm深度附近达到最高值,其后不断降低并趋于平稳,Cd、Hg、Cu、Pb和Zn变异幅度大,受到人为干扰较大,As、Cr和Ni主要受成土母质控制,属于自然来源,变动幅度较小;研究区内8种元素不存在非致癌风险,Cr、As、Ni和Cd产生的致癌风险处在可接受范围内,但存在的潜在致癌风险应引起足够的重视。     

粤北某离子吸附型稀土矿山土壤和地表水重金属分布及风险评价

对粤北某离子吸附型稀土矿24个土壤样品中的As、Cd、Cr、Cu、Mn、Ni、Pb、Zn和Hg,以及15个地表水样品中的As、Cd、Cu、Hg、Mn、Pb和Zn进行了检测,并以多元统计分析与土壤潜在生态风险指数法、地表水健康风险评价模型相结合的方式,研究了重金属的分布特征及风险水平。结果表明:在土壤中,Mn、Zn、Cd和Pb的平均含量均超过了背景值;Mn、Cr、Ni、Cu、Cd和Zn在采区有较明显集聚,As、Pb和Hg的高含量分布相对均匀;Cr、Ni、Cu和Pb含量主要受区域背景影响,Zn、As、Cd和Hg含量与矿区人类活动关系密切,Mn含量受自然和人为因素共同控制;重金属造成的土壤潜在生态风险整体处于轻微水平,Ⅱ采区和Ⅶ采区生态风险较高;Cd和Hg是造成土壤生态危害的主要重金属元素。在地表水中,Mn的平均浓度超过了《地表水环境质量标准》(GB 3838-2002)规定的限值,其余重金属的含量均满足该标准中的Ⅲ类水质要求;重金属浓度在靠近采区及位于河流中下游的位置偏高;Mn、Cd、Pb、Zn和Cu浓度受稀土开采影响较大,As、Hg浓度主要受自然因素影响;重金属产生的健康总风险(9.39×10^-7~1.01×10^-6 a^-1)低于国际辐射防护委员会推荐的参考标准(5×10^-5 a^-1),但儿童通过饮水途径受到的健康风险(1.01×10^-6 a^-1)略超过部分机构的推荐限值;Cd和As是地表水中产生健康风险的主要重金属元素。综上,研究区重金属污染风险管理的主要对象是Cd和Mn。     

三峡库区柑橘对土壤重金属吸收富集特征研究

研究区域柑橘果实重金属含量符合NY/T 426-2000<绿色食品柑橘>标准,果实品质达到一级产品.土壤中重金属的含量越高,柑橘叶片、果皮、果肉的重金属含量也越高.柑橘叶片对土壤重金属铜、锌、铅、镉、镍、汞、砷、铬的吸收富集能力显著大于果皮与果肉,果皮对土壤重金属铜、锌、铅、镉、汞的吸收富集能力显著大于果肉,果肉对土壤重金属铬的吸收富集能力显著大于果皮.柑橘同一部位对土壤中不同重金属元素的吸收富集能力也存在很大的差异,柑橘叶片对土壤中不同重金属元素的富集系数大小顺序为Hg＞Pb＞Cd＞Cu＞Zn＞Cr＞As＞Ni,柑橘果皮对土壤中不同重金属元素的富集系数大小顺序为Cd＞Hg＞Cu＞Zn＞Pb＞Cr＞Ni＞As,柑橘果肉对土壤中不同重金属元素的富集系数大小顺序为Hg＞Cu＞Cr＞Zn＞Cd＞Ni＞Pb＞As.     

成都市地表灰尘重金属污染分布特征及健康风险评价

对成都市中心城区娱乐区、居民区、商业区和城市广场等日常活动区域代表点的地表灰尘中的重金属进行监测,分析其污染分布特征,并应用美国EPA人体暴露风险评价方法对地表灰尘进行了健康风险评价。结果表明,研究区域地表灰尘重金属污染较为严重,Pb、Zn、Cu、Ni、Cr、Cd的平均含量分别为成都市土壤背景值的1.18~77.57倍,其中Cd的富集因子大于10,污染极强且富集在颗粒物中。暴露模型计算表明,重金属慢性每日平均暴露量为手-口摄入量皮肤吸收量吸入空气量,经手-口接触行为是人体地表灰尘暴露风险的主要途径。儿童重金属非致癌风险CrPbCdCuZnNi,成人重金属非致癌风险PbCrCdCuZnNi,且均小于非致癌风险阈值1,不会对城市人群造成明显伤害。重金属致癌风险CrCdNi,均低于致癌风险阈值,表明不具有致癌风险,但潜在生态危害值得重视。     

贵州省典型农业区土壤重金属污染及在蔬菜中的富集研究

选择贵州省遵义县4个镇典型农业区,研究重金属含量和污染特征以及在蔬菜中的富集作用.结果表明,由于贵州省重金属本底值普遍较高,遵义县虾子镇、永乐镇、新舟镇和喇叭镇土壤Cd、Hg、As均有超标,Cd的超标率分别为64.3%、31.3%、23.5%和6.3%,Hg的超标率分别为37.5%、11.8%、12.5%和28.6%,As的超标率分别为6.3%、23.5%、31.3%和28.6%;从蔬幕对重金属的富集作用来看,辣椒、西红柿对于Cd有较强的富集作用,豇豆对As的富集系数略高于其它蔬菜,黄瓜、豇豆对Hg的富集强于对其它重金属元素的富集.     

Variations in the level of some trace elements in hair of participants in the Italian expeditions in Antarctica

As a part the Italian National Programme of Research in Antarctica (PNRA) a monitoring study has been undertaken to quantify the concentrations of some selected trace elements in human hair of participants in the Antarctic expeditions. Such concentrations may vary as a consequence of the extreme environmental conditions and changes in lifestyle experienced by participants in the expeditions, as some evidence in previous investigations seems to suggest. The present study regards samples collected on the occasion of the 2002-2003 expedition to the Italian Base of Terra Nova Bay (now Mario Zucchelli Base), i.e., just before the expedition and about one month later. Seven essential elements were taken into account, namely, Ca, Cu, Cr, Fe, Mg, Mn and Mo. Determinations were performed by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) and Dynamic Reaction Cell Inductively Coupled Plasma Mass Spectrometry (DRC-ICP-MS). Data obtained were statistically treated by using the non-parametric Friedman test. The concentrations of Ca, Cu and Mg were found to decrease (P < 0.05). The stress caused by the severe environmental conditions might well play a role in the observed decrease.     

淮南市秋季大气可吸入颗粒物中多环芳烃的污染特征分析

2007年秋季在淮南市五个采样点采集大气可吸入颗粒物样品,用色谱-质谱法分析多环芳烃中16种优控污染物.结果显示,交通区PAHs浓度最高;PAHs以四环为主,二环所占比例最小;PM10与ΣPAHs成显著正相关关系,与苯并[a]芘成显著正相关;采用比值法对准南市PM10中的PAHs进行来源分析,得到PAHs主要来源于交通源及燃煤排放.     

河流沉积物中有机污染物的分析研究进展

总结了近年来河流沉积物中有机污染物的研究进展 ,集中评述了国内有关沉积物中多环芳烃、有机氯农药和多氯联苯的分析研究现状 ,包括样品采集、样品前处理和样品分析 ,并对今后河流、湖泊及水库沉积物中污染物的分析工作作了展望     

天津市空气颗粒物中酞酸酯的分布特征

采用气相色谱-质谱仪(GC-MS)对天津市空气颗粒物中15种酞酸酯(PAEs)夏季和冬季的浓度进行了分析测定,研究了酞酸酯污染水平的季节变化,不同季节酞酸酯的功能区差异,15种酞酸酯在颗粒物中的分布特征,以及DBP和DEHP在夏冬两季中的污染特点,分析了产生上述结果的原因,基本说明了天津市空气颗粒物中酞酸酯的污染状况和特点。     

PCR技术对水中病原体的检测

水中有病毒、细菌、原生动物、蠕虫等多种病原体。常规的检测方法是用大肠菌作为病原体的指示生物,但是大肠菌的生存特性与病毒、原生动物差异较大,难以指示病毒、原生动物的存在与否。对每一种病原体单独进行检测,费时、费力。由于PCR技术具有快速、灵敏、特异的特点,使得它对于水中病原体的检测具有较高的应用价值。     

Distribution of natural radionuclides in surface soils in the vicinity of abandoned uranium mines in Serbia

The activity concentrations of natural radionuclides in soils from the area affected by uranium mining at Stara Planina Mountain in Serbia were studied and compared with the results obtained from an area with no mining activities (background area). In the affected area, the activity concentrations ranged from 1.75 to 19.2 mg kg^?1 for uranium and from 1.57 to 26.9 mg kg^?1 for thorium which is several-fold higher than those in the background area. The Th/U, K/U, and K/Th activity ratios were also determined and compared with data from similar studies worldwide. External gamma dose rate in the air due to uranium, thorium, and potassium at 1 m above ground level in the area affected by uranium mining was found to be 91.3 nGy h^?1, i.e., about two-fold higher than that in background area. The results of this preliminary study indicate the importance of radiological evaluation of the area and implementation of remedial measures in order to prevent further dispersion of radionuclides in the environment.     

Determination of Heavy Metals in Water from Boreholes in Dumasi in the Wassa West District of Western Region of Republic of Ghana

Concentrations of heavy metals in the borehole at Dumasi in the Wassa West District of the Republic of Ghana have been measured in this study. The concentrations of the following metals in the ground water from Dumasi borehole are: Iron (Fe) – 7.52 ppm, Manganese (Mn) – 1.11 ppm, Arsenic (As) – 4.52 ppm, Chromium (Cr) – 0.026 ppm, Cobalt (Co) – 0.01 ppm, Zinc (Zn) – 0.007 ppm, Cadmium (Cd) – 0.002 ppm and Lead (Pb) – 0.005 ppm. The results of the study show that resident adults and children who use water from the boreholes are at serious risk from exposure to health hazards associated with exposure to the above metals in the boreholes in Dumasi. If the results of this study are applied to other mining communities, which lie on the Birimian and Tarkwaian rock system, then the residents are at serious risk from exposure to toxic metals from drinking water from the boreholes dug for them by mining companies operating in their communities.     

Profile of PAH in the Exhaust of Gasoline Driven Vehicles in Delhi

A preliminary study to determine the profile of PAHs in the exhaust of gasoline vehicles in Delhi was conducted. Three different types of vehicles (cars, autorickshaws and scooters) were selected with different age groups for sampling purpose. The concentration of Total PAHs (Σ₁₂PAHs) was found to be 27.27 ± 2.27, 28.61 ± 3.70 and 29.81 ± 3.57 mg/g in the exhaust of cars, auto- rickshaws (three wheelers) and two wheelers, respectively. The levels of PAHs were found to be high in scooter exhaust as compared to that of cars and autorickshaws. The total PAHs concentration in the present study was found to be higher as compared to other studies. Such a high concentration could be attributed to different parameters like the age of the vehicles, driving conditions, the fuel quality and the emission standards.     

陇东油区土壤中芳烃分布特征及来源分析

通过采集陇东黄土塬区华庆、马岭和西峰油区的土壤样品,分析研究芳烃在不同剖面土壤中的分布特征及母质来源。结果显示:三油区土壤中均检测到萘、菲、艹屈、联苯、苯并芘、苯并荧蒽和三芳甾烷;萘、菲、艹屈和联苯均具有不同甲基化修饰的衍生物,且不同甲基化程度的衍生物含量呈简单的正态分布趋势;芳烃含量最多的是萘,其次是菲、艹屈和联苯;三油区土壤的成烃环境相似,均是淡-微咸水环境,且都有丰富的水生生物尤其是高等水生植物输入,同时芳烃物甲基化表明成烃环境经历了剧烈的微生物作用过程。     

Management of air quality in the vicinity of congested area in Kuwait

An assessment of air quality in the vicinity of a selected school has been carried out by monitoring the concentrations of primary pollutants. The results has shown that during the school hours, the measured pollutants emitted from the cars next to the selected school, such as CO and NO(2), are always under the allowable limits for Kuwaiti air quality standards. On the other hand, the concentrations of non methane hydrocarbon pollutant (nm-HC), some of which are considered to be cancergenic, are found to be above the Kuwaiti standard most of the times. A traffic counter is used to record the number of cars in the main road next to the school in 15 min intervals for 10 days during the monitoring period for air quality. Statistical analysis is performed to develop a relation for prediction of the necessary reduction in traffic, based on CO concentrations, during morning and afternoon periods on working days. A computer dispersion model (CALINE4) is also used to assess the CO concentrations based on recorded flow of traffic and emission inventory with the prevailing meteorological conditions existed at the specified time. After the validation of model, different scenarios have been evaluated to provide an acceptable solution to resolve the traffic congestion problem near the schools in the early morning hours with substantial reduction in pollution levels. The optimal solution for CO concentration reduction by managing smooth traffic flow is to reduce the traffic intensity by half in early morning and afternoon rush hours. The results of the predicted CO concentration in the vicinity of the school for the model and the statistical analysis has shown reduction of 30% and 42% respectively, for approximately 50% decrease in the car use. On the other hand the predicted CO concentration for the model and the statistics reached 24% and 33% respectively when 50% of students opted for buses instead of using private cars.