肠杆菌FM-1强化积雪草修复镉污染土壤机理

分析了肠杆菌FM-1的耐镉性及促生特性，并研究了肠杆菌FM-1对矿山型和非矿山型积雪草镉富集及根际土壤pH值的影响.结果表明，肠杆菌FM-1对镉有较强的耐受性，其分泌的吲哚乙酸含量，铁载体A/A_r值和溶磷能力分别达到（72.85±0.62）mg/L，0.21±0.01和（143.33±2.13）mg/L，表明肠杆菌FM-1具有良好的促生能力.将肠杆菌FM-1接种于采自广西柳州泗顶铅锌矿周边4种类型的土壤中，均不同程度提高了矿山型和非矿山型积雪草对镉的富集.其中，下游区土壤接种肠杆菌FM-1后，矿山型积雪草茎和叶中镉含量分别增加了87.90%~161.84%和21.85%~76.42%，非矿山型叶片中的镉含量增加了5.84%~35.20%.研究表明肠杆菌FM-1促进了积雪草对镉的富集.同时，肠杆菌FM-1的添加在一定程度上影响了积雪草根际土壤的pH值，显著降低了下游区矿山型积雪草根际土壤中的pH值.     

Maternal exposure to specific perfluoroalkyl substances is associated with increasing blood glucose in pregnant women

正Imagine if a group of toxic substances that increase oxidative stress and disrupt glucose and lipid metabolism have been broadly used worldwide for applications such as repellent,food packaging,and non-stick frying pan coatings.Now imagine if some of these substances have half-lives as long as 3-8 years.This is an environmental reality that has come to light with perfluoroalkyl and polyfluoroalkyl substances(PFASs)–high     

Global-scale environmental transport of persistent organic pollutants

In order to realistically simulate both chemistry and transport of atmospheric organic pollutants, it is indispensable that the applied models explicitly include coupling between different components of the global environment such as atmosphere, hydrosphere, cryosphere and soil system. A model with such properties is presented.

The atmospheric part of the model is based on the equations in a general contravariant form which permits easy changes of the coordinate system by redefining the metric tensor of a specifically employed coordinate system. Considering a need to include explicitly the terrain effects, the terrain following spherical coordinate system is chosen from among many possible coordinate systems. This particular system is a combination of the Gal-Chen coordinates, commonly employed in mesoscale meteorological models, and the spherical coordinates, typical for global atmospheric models.

In addition to atmospheric transport, the model also simulates the exchange between air and different types of underlying surfaces such as water, soil, snow, and ice. This approach permits a realistic representation of absorption and delayed re-emission of pollutants from the surface to the atmosphere and, consequently, allows to capture hysteresis-like effects of the exchange between the atmosphere and the other components of the system. In this model, the most comprehensive numerical representation of the exchange is that for soil. In particular, the model includes a realistic soil module which simulates both diffusion and convection of a tracer driven by evaporation from the soil, precipitation, and gravity.

The model is applied to a long-term simulation of the transport of pesticides (hexachlorocyclohexanes in particular). Emission fluxes from the soil are rigorously computed on the basis of the realistic data of the agricultural application. All four modelled systems, i.e. atmosphere, soil, hydrosphere and cryosphere, are driven by objectively analysed meteorological data supplemented, when necessary, by climatological information. Therefore, the verification against the observed data is possible. The comparison of the model results and the observations taken at remote stations in the Arctic indicates that the presented global modelling system is able to capture both trends and short-term components in the observed time series of the concentrations, and therefore, provides a useful tool for the evaluation of the source–receptor relationships.     

新兴污染物对微藻的毒性作用与机制研究进展

随着科技的发展,监测手段不断进步,新兴污染物普遍存在于环境中的问题及其可能带来的危害近年来才开始受到重视和研究。微藻作为初级生产者,对维持生态系统的稳定和平衡起到了至关重要的作用。本文综述了包括全氟化合物、多环芳烃、药品及个人护理品、纳米材料、微塑料和稀土元素在内的新兴污染物对微藻毒性作用及机制的研究进展。重点针对微藻的种间关系、生长和形态、对污染物的吸收和代谢、氧化应激反应、光合作用及基因表达等方面进行了总结,分析了新兴污染物作用下微藻的响应规律,归纳了新型污染物作用于微藻的毒性影响与可能机制。最后思考了其中可能存在的问题,提出了几点建议和展望。     

三氯生在水生生态系统中的污染现状及其生物毒性效应

三氯生(triclosan, TCS)是一种合成型广谱类抗菌剂,广泛应用于人类的生产生活,使用中伴随生活污水进入环境并已广泛分布,其中水生生态系统是TCS的主要污染区域之一。通过汇总分析国内外不同类型水生生态系统中TCS的调查研究结果,发现TCS已经普遍存在于淡水和近海水生生态系统中,生活污染处理厂出水是河流中TCS的主要污染源,区域污染水平与人口密度和工业发展程度密切相关;水体中的浓度受降雨、河口区潮汐作用以及季节影响; TCS对水生生物存在显著毒性效应,其效应浓度因物种而异,与生物的发育阶段也有关系。     

双酚AF暴露对胚胎期和幼鱼期斑马鱼的毒性效应

为明确不同发育阶段的斑马鱼对BPAF(双酚AF)暴露的易感性,采用暴露试验法初步研究了BPAF对胚胎期和幼鱼期斑马鱼的发育毒性. 结果表明:①BPAF暴露可延缓胚胎期斑马鱼的发育和孵化,使其出现心包水肿、卵黄囊异常、心率下降、心脏搏动停止等症状. ②暴露96 h后,ρ(BPAF)为2.0、2.5、3.0 mg/L暴露组胚胎期斑马鱼的畸形率高达100%,暴露24 h致畸的EC₅₀(半数效应浓度)为2.00 mg/L,暴露96 h的LC₅₀(半数致死浓度)为1.84 mg/L. ③暴露72 h后,对照组幼鱼期斑马鱼鱼鳔发育缺陷率为0;除ρ(BPAF)为1.0 mg/L暴露组外,其余BPAF暴露组幼鱼期斑马鱼鱼鳔发育缺陷率为100%. ④随着暴露时间的延长以及中毒程度的加深,幼鱼期斑马鱼出现的中毒症状依次表现为心包水肿、卵黄囊水肿、背脊弯曲、心跳停止,暴露48和72 h时其心包水肿的EC₅₀分别为1.76、1.56 mg/L,暴露96 h的LC₅₀为1.77 mg/L. 胚胎期和幼鱼期斑马鱼对BPAF暴露响应的差异分析显示,幼鱼期斑马鱼对BPAF暴露的反应更为敏感,幼鱼期斑马鱼的心包水肿症状可作为BPAF毒性响应的最佳指标之一.      

河蚬在我国沉积物毒性评价与鉴定中的应用研究

河蚬作为原产并广泛分布于我国及东南亚的双壳类淡水软体动物,是我国众多水域的底栖优势种。河蚬对水体污染物具有较强累积能力,已成功用于水体沉积物生物富集及生物毒性效应研究。但应用于沉积物毒性鉴别评估(TIE)研究整体上仍处于起步阶段,尚未形成一套标准指标测定方法和技术体系。为此,本研究在调查底栖生物在我国沉积物毒性研究的基础上,以河蚬为主要研究对象,探讨其在我国生态分布等生物学背景,系统分析其对重金属和有机污染物的生物富集特征以及相关生物毒性效应方面的研究进展,以期为河蚬作为我国特色的沉积物毒性鉴别评估(TIE)受试生物提供参考依据。     

四溴双酚A对太平洋真宽水蚤的急性毒性及氧化胁迫

为了研究四溴双酚A(tetrabromobis-phenol A,TBBPA)对海洋桡足类的急性毒性和氧化胁迫效应,以太平洋真宽水蚤为受试生物,测定了TBBPA对其96 h急性毒性和对其体内抗氧化防御系统的影响。结果表明,TBBPA对太平洋真宽水蚤的96 h半数致死浓度(96 h-LC50)为178μg·L~(-1),95%可信区间为91~306μg·L~(-1),表现为极毒。亚致死浓度下,TBBPA能够不同程度影响太平洋真宽水蚤的抗氧化防御酶活力以及非酶物质含量。其中SOD和GST活性的变化趋势较为一致,暴露初期SOD和GST活性显著上升(P0.05),随暴露时间延长酶活性有所下降,最终趋向对照组水平;GPx活性水平始终维持在对照组以上并且差异显著(P0.05);暴露初期,GSH含量受轻微氧化压力而轻微升高,暴露48 h后GSH含量急剧下降并显著低于对照组(P0.05)。太平洋真宽水蚤体内SOD、GST、GPx活性和GSH含量对TBBPA暴露均十分敏感,能够为海洋环境的TBBPA监测提供生化指标参考。     

沉积物中芘对泥鳅和霍甫水丝蚓的毒性效应研究

积累在沉积物中的外源化合物会对底栖生物产生危害。本研究以泥鳅(Misgurnus anguilicaudatus)和霍甫水丝蚓(Limnodrilus hoffmeisteri)为受试生物,研究了沉积物中代表性多环芳烃类物质芘(pyrene)对这2种生物的急/慢性毒性效应。芘对泥鳅96 h的半数致死浓度LC50、平衡受损效应浓度EC10和EC50分别为548.9、63.1、254.8 mg·kg~(-1)干重,21 d的LC50为4.6 mg·kg~(-1)。沉积物中芘会导致泥鳅活动异常、泥鳅体色加深、抑制泥鳅生长。芘对霍甫水丝蚓28 d的LC50、自断效应浓度EC10和EC50分别为1 000、5.1、85.4 mg·kg~(-1)。芘也会抑制霍甫水丝蚓的生长,引起霍甫水丝蚓挖掘深度变浅、挖掘长度变短、挖掘密度变小,导致霍甫水丝蚓产生沉积物回避行为,降低霍甫水丝蚓筑巢密度和大小。霍甫水丝蚓的挖掘、沉积物回避和筑巢等行为产生不同程度的影响。泥鳅对芘的毒害响应较霍甫水丝蚓更加敏感。研究结果丰富了我国本土底栖生物毒性效应数据,为沉积物质量基准的制定奠定了基础。     

Copeland计分排序法在化学物质生态危害评价中的应用

运用Copeland计分排序法,根据61种环境优先污染物的7项环境行为和生物毒性指标对其进行生态危害评价,其中POPs名单中的化学物质排名靠前.通过分别对比不同氯取代的苯酚类和苯类化学物质的排名情况,得出化学物质的生态危害与其氯取代程度成正比;将61种环境优先污染物的Copeland计分排序法的结果与日本环境省公布的环境评价结果对比发现,其Pearson相关系数达到0.989 9,表明了二者基本相符;初步尝试了通过Copeland计分排序法预测新化学物质的生态危害排序,排序结果基本合理.