Sueishi T, Morioka T, Kaneko H, Kusaka M, Yagi S, Chikami S
Department of Environmental Engineering, Osaka University, Suita, Japan.
Regul Toxicol Pharmacol. 1988 Mar;8(1):4-21. doi: 10.1016/0273-2300(88)90003-7.
Environmental risk incurred with the use of synthetic surfactants is dealt with in this paper. The background and necessity of risk management related to surfactant usage in the Lake Biwa basin are introduced, as well as a research scheme that acknowledges risks in three sub-processes--consumption and discharge, fate in aquatic environment, and ecotoxicological response of linear alkylbenzene sulfonate (LAS). The ayu (Plecoglossus altivelis) has been selected as the significant biological target in the basin. Results of a field survey of the behavior of LAS along streams flowing down to the lake are presented. Included are the estimation and verification of an original unit of surfactant consumption per capita per day based on LAS and MBAS concentrations observed in diurnal monitoring. A simulation model representing the flowdown process of LAS dynamically is formulated, with which longitudinal dispersion, settling, and modified biodegradation of LAS are evaluated in the field survey. On the basis of the research scheme described above, ecotoxicological laboratory tests on ayu have been carried out. The special significance of acute and subchronic effects on ayu in various life stages exposed to low concentrations of LAS can be recognized. It has been concluded that the LC50 of young ayu is not greater than 0.1 ppm under the disadvantageous condition of high temperature or extreme hardness even in normal ranges of environmental indicators. An advanced plan of risk management for surfactant usage is proposed based on methods of elevated risk, comparative risk, risk--benefit, and balanced risk. The occurrence and magnitude of risk phenomena in each subdivided basin adjacent to the lake are identified, taking into consideration features such as (1) the spawning place of ayu and aquafarms, (2) COD and MBAS concentrations and their tolerable levels in current regulation of stream pollution, (3) socioeconomic perspectives including recreational activities and voluntary actions to improve the neighborhood environment, and (4) future preparation of measures for resolving technological risk including sewerage construction. Because LAS concentrations in several rivers exceed the tolerable level of the most delicate life stage of ayu, latent environmental effects can be suggested. It is concluded therefore that it is necessary to establish a water quality goal related to surfactants that takes patterns of water use and conservation of the ecosystem in the local environment into consideration. These judgments are followed by formulation of the "requirement" for environmental management practice for the Lake Biwa administration.
本文探讨了使用合成表面活性剂所带来的环境风险。介绍了琵琶湖流域与表面活性剂使用相关的风险管理背景和必要性，以及一种研究方案，该方案认识到线性烷基苯磺酸盐（LAS）在三个子过程中的风险，即消费和排放、在水环境中的归宿以及生态毒理学响应。已选定香鱼（Plecoglossus altivelis）作为该流域的重要生物目标。给出了沿流入湖泊的溪流对LAS行为进行实地调查的结果。其中包括根据日间监测中观察到的LAS和MBAS浓度，对人均每日表面活性剂消费量的原始单位进行估算和验证。构建了一个动态表示LAS向下游流动过程的模拟模型，利用该模型在实地调查中评估LAS的纵向扩散、沉降和修正生物降解。基于上述研究方案，已对香鱼进行了生态毒理学实验室测试。可以认识到低浓度LAS对香鱼不同生命阶段的急性和亚慢性影响具有特殊意义。得出的结论是，即使在环境指标的正常范围内，在高温或极端硬度等不利条件下，幼香鱼的半数致死浓度（LC50）不超过0.1 ppm。基于高风险、比较风险、风险效益和平衡风险的方法，提出了表面活性剂使用风险管理的先进计划。考虑到以下特征，确定了与湖泊相邻的每个细分流域中风险现象的发生情况和严重程度：（1）香鱼的产卵地和水产养殖场；（2）河流污染现行法规中的化学需氧量（COD）和MBAS浓度及其可容忍水平；（3）包括娱乐活动和改善邻里环境的自愿行动在内的社会经济观点；（4）解决包括下水道建设在内的技术风险的未来措施准备情况。由于几条河流中的LAS浓度超过了香鱼最脆弱生命阶段的可容忍水平，因此可以推测存在潜在的环境影响。因此得出结论，有必要制定一个与表面活性剂相关的水质目标，该目标应考虑当地环境中的用水模式和生态系统保护。这些判断之后是为琵琶湖管理制定环境管理实践的“要求”。
