重金属对药物和个人护理品在土壤/沉积物中吸附的影响机制:现状与展望

药物和个人护理品简称(PPCPs)是一类具有潜在累积效果的环境污染物,其广泛分布于水体与土壤环境中.在土壤/沉积物中,PPCPs将发生一系列的物理、化学和生物作用,其中吸附是PPCPs在土壤/沉积物中极为关键的环境行为,将影响PPCPs在环境中的迁移转化及其对生物体的危害程度.重金属作为一类常见的无机污染物,它们的存在会影响PPCPs在土壤/沉积物表面的吸附行为,对土壤/沉积物吸附PPCPs的吸附效果造成不同影响.本文归纳总结了重金属存在时,PPCPs在土壤/沉积物中的吸附机理,综合探讨了PPCPs官能团组成、重金属离子类型、pH、离子强度和有机质等因素对PPCPs吸附的影响,并针对以往研究存在的问题进行了展望.     

反映我国空间分异特性的多介质环境逸度模型的构建及十溴二苯醚的归趋模拟

化学品的浓度水平、排放量都与具体的地理位置密切相关,发展具有空间分异特性的多介质环境逸度模型,可更加准确地描述化学品的多介质环境归趋.本研究基于我国的区域环境属性,建立了 50 kmx50 km分辨率的空间分异Ⅲ级多介质环境逸度模型.以阻燃剂十溴二苯醚(BDE-209)为例,模拟和预测了 BDE-209在我国的多介质环境中的分布.结果表明,上海、山东和广东等东部地区大气与土壤中BDE-209浓度较高,陕西、山西等中西部地区水与沉积物内BDE-209浓度较高.BDE-209在大气、水、土壤和沉积物中的平均浓度分别为2.02×10-6 μg·m-3、6.64×10-6μg·m-3、1.93 μg·kg-1 和3.65×10 μg·kg-1.土壤和沉积物是BDE-209主要的汇,其含量占其环境总量的98.65％.所构建的具有空间分异特性的多介质环境逸度模型,适用于持久性有毒化学物质在我国环境中的归趋模拟,有助于化学品的环境风险预测与管理.     

疏水性有机污染物在土壤/沉积物中的赋存状态研究

土壤/沉积物是环境中有机污染物主要的汇,由于土壤-沉积物结构和性质的复杂性,有机污染物进入其中,会结合在不同的位点上,赋存状态发生分化,具有不同的物理流动性、生态风险和化学反应活性.对于土壤-沉积物中有机污染物吸附/解吸的研究是认识其赋存状态并预测其生态风险的重要手段.本文对于疏水性污染物吸附/解吸及赋存状态的国内外研...     

有机质官能团及微孔特性对疏水性有机污染物吸附的影响机制

作为重要的地质吸附剂,土壤/沉积物中的有机质是环境中疏水性有机污染物主要的汇.由于有机质的结构异质性,疏水性有机污染物一旦进入其中,会被吸附在不同的位点上,反应活性和生态风险进而会发生变化.对疏水性有机污染物在有机质上的吸附进行研究有助于了解其在环境中的分布,传输及生物有效性.本文就疏水性有机污染物在土壤/沉积物中的有机质上吸附的国内外研究进展进行了综述,讨论了重要有机质组分(腐殖质和碳黑)的结构和吸附作用差异性,重点分析了有机质的微孔特性和官能团对吸附的影响机制.     

高效液相色谱-三重四极杆串联质谱测定环境水样中20种环境内分泌干扰物

环境内分泌干扰物(EDCs)是指干扰生物体内保持自身平衡和调节发育过程中天然激素的外源性化学物质.因EDCs对环境暴露生物体正常生长发育和繁殖带来的潜在危害,其已成为当前科学界和公众共同关注的热点问题之一.本论文建立了固相萃取-高效液相色谱-串联质谱测定水样中4类EDCs(孕激素、雄激素、雌激素和烷基酚)的分析方法.水样通过HLB小柱进行固相萃取和纯化,以甲醇和水为正模式流动相,孕激素和雄激素等物质在正模式下响应高;甲醇和0.1%氨水为负模式流动相,雌激素和烷基酚等物质在负模式下响应高.20种EDCs的定量分析通过三重四极杆串联质谱多反应监测模式分析.各目标物的检出限为0.04—0.51 ng·L~(-1),定量限为0.13—1.70 ng·L~(-1),回收率为76.1%—121.6%,相对标准偏差15%.应用该方法对不同水体(河流水、湖泊水和生活污水)中EDCs的分布状况进行了初步调查,发现EDCs广泛存在于表层水样中,浓度范围为ND—981.1 ng·L~(-1).     

阳离子表面活性剂对沉积物及其主要组分吸附双酚A的影响

采用吸附实验、选择性萃取技术研究阳离子表面活性剂-十六烷基三甲基溴化铵(CTMAB)对表层沉积物(生物膜)吸附双酚A(BPA)的影响规律,及CTMAB不同加入条件下对表层沉积物(生物膜)选择性萃取(铁氧化物、锰氧化物、有机质)后的组分吸附BPA的影响.CTMAB对表层沉积物(生物膜)吸附BPA起到促进作用,且随着CTMAB浓度的增加,其促进作用增强;CTMAB掺杂顺序对表层沉积物吸附BPA的影响较小,但对生物膜吸附BPA的影响较大;CTMAB的引入导致BPA在选择性萃取后的表层沉积物(生物膜)组分上的吸附量显著增加,并且CTMAB对表层沉积物(生物膜)吸附BPA的促进作用远大于表层沉积物(生物膜)自身主要组分理化性质的影响.选择性萃取证明,阳离子表面活性剂的引入能降低BPA在水体环境中的迁移转化能力.     

环境因子对海州湾表层沉积物中氨氮吸附-解吸的影响

沉积物中的有机质在微生物作用下矿化,产生大量氨氮,大部分氨氮会被沉积物颗粒吸附,影响氮在沉积物中的硝化、反硝化以及厌氧氨氧化等作用,因此,沉积物对氨氮的吸附-解吸作用是影响沉积物中氮循环的一个重要过程。海湾具有水动力作用强烈,扰动和盐度等物理化学条件复杂多变的特点,研究环境条件变化对沉积物中氨氮吸附-解吸的影响有助于揭示其对沉积物-水界面氮营养盐交换的影响机制。因此,以海州湾表层沉积物样品进行室内模拟实验,通过吸附-解吸动力学和热力学实验,研究扰动大小、粒度分布和盐度等环境因子对氨氮吸附-解吸的影响。结果表明,吸附和解吸是一个复合动力学过程,主要在30 min内完成,30 min以后逐渐达到动力学平衡状态;准二级吸附动力学方程和修正的Elovich模型对沉积物吸附氨氮的模拟效果较好,一级反应动力学方程可以较好地描述沉积物对氨氮的解吸动力学过程。热力学模型的拟合结果显示沉积物对氨氮的吸附符合Henry模型,描述解吸过程的最优模型是Langmuir模型。一定范围内振荡频率的增加、粒径的减小、盐度的降低都会提高沉积物对氨氮的吸附能力;一定范围内振荡频率的增加、粒度的增大、盐度的升高都会增强沉积物对氨氮的解吸量。该研究可为进一步认识和理解环境因子变化对氨氮吸附-解吸的影响及机制提供理论依据。     

污水中内分泌干扰物的去除技术研究进展

内分泌干扰物(EDCs)在水环境中广泛存在,对生物体生存和繁衍危害巨大,是改善水质、保障生态安全的一个世界性环境问题.对于污水中EDCs的去除,常用的方法包括物理方法、高级化学氧化和生物降解.物理方法主要包括活性炭法和膜分离技术,这2种技术对EDCs具有较好的去除效果,但活性炭的吸附能力随着运行时间的增长和EDCs浓度的增加而减弱,而膜分离技术对EDCs的去除效率受EDCs的物化属性和膜本身特性等因素的影响;高级化学氧化法降解EDCs的关键是氧化剂的选择,氯化去除EDCs易产生副产物,相比而言O3、UV/H2O2和其它联合技术对EDCs的去除效果更明显;生物降解从EDCs的去除率、运行条件和评价方法方面进行了分析,在化学沉降法、活性污泥法和滴流生物滤器3种工艺中,活性污泥法对EDCs的去除效率最高,生物降解EDCs的效果主要受处理工艺类型、水力停留时间、泥龄、温度、溶解氧等因素的影响,由于化学分析的局限性,结合生物测试的方法来评价EDCs的去除效果将更为全面;最后结合实际对各种技术的应用前景进行了分析和展望,相比其他技术而言生物处理技术有一定的优势,以生物单元为主体的综合处理过程将成为未来去除EDCs最经济实用的方法,而结合化学分析和生物测试来综合评价EDCs的去除效果也将成为研究的重要的评价手段.     

苄嘧磺隆在两种可变电荷土壤中的吸附

研究了两种典型可变电荷土壤对磺酰脲类除草剂——苄嘧磺隆(bensulfuron-methyl,BSM)的等温吸附和吸附动力学,及pH对土壤吸附苄嘧磺隆的影响。结果表明,土壤吸附苄嘧磺隆的量随着苄嘧磺隆的质量浓度的升高而增加,而随溶液pH的升高逐渐减小;土壤的物理和化学性质也影响其吸附苄嘧磺隆的量。用Langmuir、Freundlich、Dubinin-Redushkerich等方程对供试土样吸附BSM的数据进行了拟合,分析比较发现土壤吸附苄嘧磺隆的等温曲线较好地符合Freundlich方程。动力学研究显示一级动力学方程能很好地拟合供试土壤的动力学特性,苄嘧磺隆在红壤中较早达到吸附平衡。     

北江中下游内分泌干扰物的空间分布、生态风险及产业相关性

为了解北江中下游内分泌干扰物(endocrine disrupting chemicals,EDCs)空间分布及生态风险,利用LC-MS/MS和GC-MS对北江中下游8个水源地、8个典型种植业下游、5个典型水产养殖业下游及4个大型污水处理厂水样中10种EDCs进行分析.结果 表明,10种目标EDCs有6种低于检出限,仅双酚A、雌酮、辛基酚和壬基酚有检出,其中双酚A、壬基酚为北江中下游中主要EDCs,平均浓度分别为360 ng·L-1和382 ng·L-1.空间分布与影响因素分析表明,宏观因素影响区域EDCs浓度整体水平,水源地中辛基酚与壬基酚分别与第一、第二产业总值有明显相关性;局部浓度水平受产业类型、产品种类与上下游等因素影响,种植业、水产养殖业下游EDCs浓度水平主要受区域种植、养殖面积影响,其次是种植、养殖产品种类,污水处理厂出水EDCs浓度与设计处理量、服务人口呈强烈正相关.生态风险评价显示,双酚A、辛基酚和壬基酚生态风险随流域流向逐渐升高,启示对单位长度河段生态风险的变化率分析有助于确定EDCs污染源头.     

Sorption of tetracycline to sediments and soils: assessing the roles of pH,the presence of cadmium and properties of sediments and soils

Batch sorption experiments were conducted to evaluate the sorption behavior of tetracycline (TC, H₃L) on sediments and soils in the presence and absence of cadmium (Cd), as affected by pH and properties of sediments and soils. The results indicated stronger nonlinearity and higher capacity of TC sorption on sediments than on soils. Sorption of TC also strongly depended on environmental factors and sediment/soil properties. Lower pH facilitated TC sorption through a cation exchange mechanism, which also took place at pH values above 5.5, where TC existed as a zwitterion (H₂L⁰) or anions (HL^- and L^2-). When pH was above 7, however, ligand-promoted dissolution of TC might occur due to TC weakening the Al-O bond of aluminum oxide and the Fe-O bond of iron oxide. Natural organic matter (NOM) plays a more important role in TC sorption than cation exchange capacity (CEC) and clay contents. The presence of Cd (II) increased TC sorption on both sediments and soils, which resulted from the decrease of equilibrium solution pH caused by Cd²⁺ exchange with H⁺ ions of sediment/soil surfaces. The increase of TC sorption was also related to the formation of TC-Cd complexes, where Cd²⁺ acted as a bridge between the sediment/soil and TC.     

包气带不同深度土壤对甲苯和三氯乙烯的吸附研究

采用批实验研究了华北平原地下水中检出率较高的三氯乙烯和甲苯在沿污水河包气带不同深度土壤中的吸附情况。从3个地点分析结果来看,其中有机碳（OC）的质量分数均较低（最高为1.01%）。在河床和近河处土壤对甲苯和三氯乙烯的吸附总体上呈现出浅部土壤吸附性强的特点。在实验浓度范围内,土壤中无机矿物对有机污染物（特别是三氯乙烯）的表面吸附扮演了重要角色。土壤对甲苯的吸附表现出了强烈的非线性,而对三氯乙烯的吸附表现出了良好的线性关系。甲苯的吸附与土壤有机碳质量分数的关系要比三氯乙烯更密切,这说明了吸附作用过程与有机化合物的分子结构、疏水性等方面的性质也有关系。     

湘南第四纪红壤吸附SO_4~(2-)的机理研究

本文研究了湖南第四纪红粘土及其发育的旱地和水田表层土壤对SO_4~2的吸附.结果表明这三种土壤吸附SO_4~2的顺序为;红粘土>旱地红壤>红壤性水稻土.而且随介质pH的升高,SO_4~2吸附量减少,吸附机理也发生改变:当介质pH6.5以后,解吸占优势.     

长三角和珠三角农业土壤对Pb、Cu、Cd的吸附解吸特性

研究了长江三角州和珠江三角州10种代表性农业土壤对重金属Pb、Cu和Cd的吸附与解吸特性。结果表明:大多数土壤对重金属有较强吸附能力,土壤性质对重金属吸附与解吸行为有很大影响。其中,pH值是影响土壤对重金属吸附与解吸的最重要因素,土壤重金属吸附量随pH值增加而增加。土壤pH值和有机质或粘粒含量较高的土壤(如乌栅土、青紫泥田、黄斑田),其对重金属吸附能力高于pH值和有机质或粘粒含量较低的土壤(如黄筋泥、粉泥田)。重金属解吸量随重金属吸附量和土壤重金属饱和度增加呈指数增加趋势;土壤对重金属的吸附能力从强至弱依次为Pb、Cu、Cd;当3种重金属共存时,重金属之间竞争能力强弱顺序与吸附能力顺序相同。重金属之间竞争作用随土壤酸度和重金属污染程度的增加而增强。     

Effects of organic acids on Cd adsorption and desorption by two anthropic soils

The objective of this experiment was to study the effects of malic, tartaric, oxalic, and citric acid on the adsorption and desorption characteristics of Cd by two typical anthropic soils (lou soil and irrigation-silted soil) in North-west China. Cadmium adsorption and desorption were studied under a range of temperatures (25°C, 30°C, 35°C, 40°C), organic acid concentrations (0.5–5.0 mmol·L^-1), and pH values (2–8). The results showed that the Cd adsorption capacity of the lou soil was significantly greater than that of the irrigation-silted soil. Generally, Cd adsorption increased as the temperature increased. In the presence of NaNO₃, the adsorption of Cd was endothermic with ΔH values of 31.365 kJ·mol^-1 for lou soil and 28.278?kJ·mol^-1 for irrigation-silted soil. The endothermic reaction indicated that H bonds were the main driving force for Cd adsorption in both soils. However, different concentrations of organic acids showed various influences on the two soils. In the presence of citric acid, chemical adsorption and van der Waals interactions were the main driving forces for Cd adsorption rather than H bonds. Although the types of organic acids and soil properties were different, the effects of the organic acids on the adsorption and desorption of Cd were similar in the two soils. The adsorption percentage of Cd generally decreased as organic acid concentrations increased. In contrast, the adsorption percentage increased as the pH of the initial solution increased. The exception was that adsorption percentage of Cd increased slightly as oxalic acid concentrations increased. In contrast, the desorption percentage of Cd increased with increasing concentrations of organic acids but decreased as the initial solution pH increased.     

Environmental geochemistry studies in the area of Idrija mercury mine, Slovenia

Five centuries of mining and processing of mercury ore in the Idrija area have resulted in widespread contamination of different environmental compartments. Environmental impacts on a regional and local scale, caused by atmospheric emissions from the Idrija ore roasting plant, were established in the investigations of mercury spatial distribution in soil and attic dust in 160 km(2) area. Very high values were determined in the Idrijca River valley, and they decrease exponentially with the distance from Idrija. Mercury concentrations in attic dust are higher than in surrounding soils and the attic dust/soil ratio changes with distance. Measurements of mercury in the air confirmed widespread dispersion of mercury and showed highly elevated mercury concentrations around roasting plant and mine ventilation shaft. Beside, systematic monitoring of mercury contents in the stream sediments has demonstrated that huge amounts of mercury are stored in areas where ancient overbank sediments were deposited, and there was no decrease in mercury concentration in active sediments during the last 15 years. Recently, interesting and extremely polluted locations of historical small-scale roasting sites in the Idrija surroundings were discovered. Ongoing geochemical study aims to determine the extreme pollution and significance of these sites for wider contamination of soils and aquatic systems. Presented studies have shown that Hg mining in Idrija caused intense pollution of local and regional environment including the aquatic systems in the Gulf of Trieste, which is seen as the final sink of a major part of the Hg stored in soils and river sediments in the Idrija area.     

微生物对土壤和沉积物吸附多环芳烃动力学的影响

以枯草芽孢杆菌为接种微生物,研究微生物对沉积物和湿地土壤吸附菲和苯并[a]芘(BaP)吸附动力学的影响.结果表明:枯草芽孢杆菌对菲与BaP都可进行生物降解,对菲的利用率明显要大于BaP;接种微生物的土壤与沉积物对菲和BaP的吸附动力曲线与仅有微生物吸附的结果相近似,表明多环芳烃的降低主要是由于微生物的利用造成的;接种微生物后沉积物与土壤对菲的吸附量明显增大,而对BaP的吸附却降低.     

Assessment of persistent organic pollutants in soil and sediments from an urbanized flood plain area

Polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and phenolic compounds (PCs) are persistent organic compounds. Contamination of these potentially toxic organic pollutants in soils and sediments is most studied environmental compartments. In recent past, studies were carried out on PAHs, OCPs and PCs in various soils and sediments in India. But, this is the first study on these pollutants in soils and sediments from an urbanized river flood plain area in Delhi, India. During 2018, a total of fifty-four samples including twenty-seven each of soil and sediment were collected and analyzed for thirteen priority PAHs, four OCPs and six PCs. The detected concentration of ∑PAHs, ∑OCPs and ∑PCs in soils ranged between 473 and 1132, 13 and 41, and 639 and 2112 µg/kg, respectively, while their concentrations in sediments ranged between 1685 and 4010, 4.2 and 47, and 553 and 20,983 µg/kg, respectively. PAHs with 4-aromatic rings were the dominant compounds, accounting for 51 and 76% of total PAHs in soils and sediments, respectively. The contribution of seven carcinogen PAHs (7CPAHs) in soils and sediments accounted for 43% and 61%, respectively, to ∑PAHs. Among OCPs, p, p’-DDT was the dominant compound in soils, while α-HCH was found to be dominated in sediments. The concentrations of ∑CPs (chlorophenols) were dominated over ∑NPs (nitrophenols) in both the matrices. Various diagnostic tools were applied for the identification of their possible sources in soil and sediments. The observed concentrations of PAHs, OCPs and PCs were more or less comparable with the recently reports from various locations around the world including India. Soil quality guidelines and consensus-based sediment quality guidelines were applied for the assessment of ecotoxicological health effect.