Sampling method, storage and pretreatment of sediment affect AVS concentrations with consequences for bioassay responses

Sediment treatment and sediment storage may alter sediment toxicity, and consequently biotic response. Purpose of our study was to combine these three aspects (treatment-toxicity-biotic response) in one integrated approach. We used Acid Volatile Sulfide (AVS) concentrations as a proxy of the disturbance of the sediment. AVS and Simultaneously Extracted Metal (SEM) concentrations were compared to bioassay responses with the freshwater benthic macroinvertebrate Asellus aquaticus. Storage conditions and sediment treatment affected AVS but not SEM levels. AVS can be used as a proxy for sediment disturbance. The best way to pretreat the sediment for use in a bioassay in order to maintain initial AVS conditions was to sample the sediment with an Ekman grab, immediately store it in a jar without headspace, and freeze it as soon as possible. In a survey using seven different sediments, bioassay responses of A. aquaticus were correlated with SEM and AVS characteristics.     

Uncertainty in the assessment of hazard,exposure and risk

The terminology, concepts and current approaches to uncertainty in the assessment of hazard, exposure and risk are reviewed. Five generic questions are discussed on uncertainty, including sources, levels, when and how it should be dealt with or reduced, what are our gaps in understanding and how they can be addressed. A case study of lead exposure of children in Lavrion, Greece, is used to exemplify these questions and possible answers. Estimation of uncertainty may be improved by the use of interorganisational studies to capture sources of uncertainty that are often overlooked. Gaps identified in our understanding of uncertainty include: a limitation in the availability of basic measurements, a lack of knowledge of the environmental processes, an inability to predict the effects of mixtures, the aetiology of disease and devising procedures for optimal resource allocation in impact assessment.     

双柱双检测器气相色谱法同时进样分析非甲烷烃

介绍了用双柱双氢火焰离子化检测器同时进样气相色谱法分析气体样品中非甲烷烃.经过与现有方法的比较,该方法具有平行性更好、数据更准确、分析速度快等优点,各项指标均大大优于现行标准HJ/T 38-1999中的数据.通过软硬件的改进,解决了以前非甲烷烃在分析中由于在时间上所引起的数据倒置、分析误差等问题.     

突发性大气环境污染事故应急监测布点研究

采样点的布设在应急监测过程中起着至关重要的作用,科学、合理地布置采样点是应急监测的关键技术之一,采样点必须分布在整个事故影响区域。引入气体扩散模式预测事故影响范围,根据毒负荷标准在事故影响区内划分危险区。阐述了应急监测采样点布设原则及事故初期、中期、后期的特点,并对三个时期采样点布设方法进行研究。     

工程数学数理统计中的抽样理论在城市环境噪声监测优化布点中的应用探讨

用工程数学数理统计中的抽样论研究城市环境噪声监测优化布点,探讨以较少的监测点的测试数据反映整个城区的噪声水平,从而推动环境噪声监测技术的发展     

城市大气可吸入颗粒物的研究进展

可吸入颗粒物逐渐成为我国许多大中城市的首要空气污染物,对其研究是当前国际大气化学界的研究热点。纵观国内外有关可吸入颗粒物的研究进展,主要是围绕可吸入颗粒物的来源及解析技术、基本特性、采样及分析方法、对人类危害和对环境的影响等方面进行了阐述,同时也对今后的研究发展趋势进行了展望。     

塞曼效应石墨管原子吸收法测定人尿痕量镉

以磷酸二氢铵（ＮＨ４、Ｈ２ＰＯ４）作基体改良剂，用塞曼效应扣除背景直接进行石墨管原子吸收法测定尿中痕量镉，该法最低检出限为０．０２４μｇ／Ｌ，相对标准在４．５％，回收率达９５－１１２％。．     

聚酯废气组成及采样分析方法的研究

对聚酯装置工艺废气的形成，稳定性，采样方法及其浓度变化等进行了研究，结果表明，经冷的乙二醇娟收后排放出的聚酯放心气化学性质稳定，可采用聚四氟乙烯袋直接采样，采用DB－5大口径石英毛细管柱气相色谱法分析废气净化前后的有机污染物含量，净化前乙醛浓度变化在2000－30000mg/m^3之间，超出GB16297新污染源大气污染物排放限值（125mg/m^3)10-250倍，经处理后可达到国家排放标准，本方法可用于聚酯装置废气的监控。     

潮汐河流着生藻类监测采样设计

以上海黄浦江上游的藻类群落在空间和时间上的分布格局为例，讨论了用于环境质量监控的着生藻类群落分析的采样设计，设计采用收集者曲线及多元分析技术。研究表明，黄浦江着生藻类监测的采样频率每年至少４次，冬季不宜取样，条件许可应在夏季增加采样频率；综合分析宜采用年度复合样方；文中所采用的格局研究原则，同样适用于其它生物类型的采样设计。     

除草剂苯噻草胺土壤滞留因子的蒙特卡洛模拟

采用简单随机抽样和拉丁超立方抽样两种不同方法对除草剂苯噻草胺的土壤滞留因子模型进行蒙特卡洛模拟。结果表明，不同的土壤条件下，苯噻草胺的滞留因子（R）的数值呈Beta分布，最大极值为176．5，最小极值为3．3，最可能的取值在20－30的范围内。结果还显示了采用拉丁超立方抽样方法能够显著降低抽样的不均匀性，进而能降低Beta分布拟合的不确定性。本文还通过色轴在4维图上形象地表征了R值的变化。