镉的淡水水生生物水质基准研究

镉是一种有毒重金属，具有高毒性、难降解和易残留等特点，会对水生生物及水生态系统产生有害影响.为有效控制镉给水生生物带来的不利影响，亟需开展镉的水生生物基准研究，为水质标准的制订提供依据. 以我国淡水生态系统及其生物区系为保护对象，结合大量国内外文献报道的镉对我国淡水生物区系中代表物种的毒理学数据，运用评价因子法、毒性百分数排序法和物种敏感度分布法等当前国际上广泛使用的基准推导方法，研究我国淡水中镉的基准值及其推导过程. 结果表明:评价因子法得出的基准值为单值，其值为0.15 μg/L；毒性百分数排序法得出的基准值包括基准最大浓度和基准连续浓度，二者分别为7.30和0.12 μg/L；物种敏感度分布法得出的基准值分为短期危险浓度和长期危险浓度，二者分别为32.50和0.46 μg/L. 比较了3种方法的优缺点，以及与国内外已有研究基准值之间的差异及形成原因，分析了影响镉的水生生物基准的关键因素. 

Derivation of Aquatic Life Water Quality Criteria for Cadmium in Freshwater in China

Cadmium is a poisonous heavy metal which is toxic,hard to degrade and easy to reside.It can cause adverse effects on aquatic organisms and ecosystems.In order to control effectively the adverse effects which Cd might bring to aquatic life in Chinese freshwaters,it is urgent for China to derive regional aquatic life criteria for Cd,which could provide a basis for the establishment and revision of water quality standards.In this study,all available toxicity data of Cd to Chinese representative species in freshwater were collected in order to protect the freshwater ecosystem and biota system.Three widely used criteria derivation methods concerning the assessment factor method,toxicity percentile rank method and species sensitivity distribution method were