摘要
多介质环境目标值(MEG)是美国环保局推算出的化学物质在环境介质(空气、水或土壤)中的含量及排放量的限定值,某化合物的实测浓度与该化合物的MEG值之比即环境影响度(AS),AS又分为健康影响度(ASI)和生态影响度(ASII),AS值越高,表明水体受污染物的影响就越大。采用GC-MS分析了流溪河水库水体主要半挥发性有机污染物(SVOCs)的种类与含量,以MEG分别就人体健康影响度和生态环境影响度对其水质进行了评价,并测试了水体中有机物对斜生栅藻(Scenedesmus obliquus)的生态毒性效应。结果显示:流溪河水库局域水体23种EPA优先控制SVOCs总浓度分别为6.078μg·L-1和24.952μg·L-1,其中主要为苯并(a)蒽、邻苯二甲酸二丁酯以及2,4-二硝基甲苯;其健康和生态影响度均小于1,提示对健康和生态尚属安全;在流溪河水库浓缩水样的处理下,斜生栅藻生长受到轻微促进;光合色素含量和蛋白质含量均升高,其中叶绿素a涨幅最大;超氧化物歧化酶(SOD)和过氧化物酶(POD)活性总体变化趋势相同,与空白对照组相比差异显著,表明斜生栅藻抗氧化酶活性对浓缩水样的胁迫比较敏感。
The risk of water resources being contaminated by organic pollutants is of major concern. The Liuxihe reservoir is one of the most important fresh water resources for Guangzhou City, supplying nearly 60% of the city＇s fresh water demands. Identification and monitoring of these pollutants in the Liuxihe reservoir is of critical importance in an attempt to protect ecological and human health. In this study, semi- volatile organic compounds （SOVCs） in Liuxihe reservoir were determined by a gas chromatography method with mass spectrometric （GC-MS） detection. Ambient severity due to exposure to these organic pollutants was evaluated with multimedia environmental goals（MEG）. MEG is the environmental capacity of chemicals and limit values of emission which was calculated by environmental industry laboratory of United States Environmental Protection Agency（EPA）. The environmental goals in the MEG, include air, water and soil, and each one is divided into health goals and ecological objectives. Ambient severity（AS） is the ratio of the measured concentration of a compound with the corresponding value of MEG, which is divided into health severity （ASI） and ecology severity（ASII）. Higher values of AS mean pollutants cause more influ- ence on water. The results indicated that total contents of 23 different SVOCs from water samples were 6.078 txg＇L-1 and 24.952 p,g ＂L-1, re- spectively, and benzo（a） anthracene, dibutyl phthalate and 2, 4-nitrotoluene were the main SVOCs. The total ambient severity of both health and ecology was less than 1, which indicated that water in Liuxihe reservoir was still safe to health and ecology. Routine physical and chemi- cal analysis was not sufficient to make comprehensive evaluation of water quality, so the establishment of an effective test method to evaluate the ecotoxicity of organic compounds in water was of importance to environmental monitoring. The potential toxicity of water samples on the microalgae Scenedesmus obliquus was measured. Organic extra
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2013年第4期756-763,共8页
Journal of Agro-Environment Science
基金
国家自然科学基金委-广东联合基金重点项目(U0733007)
国家自然科学基金(21077052)
关键词
流溪河
有机污染物
影响度评价
毒性效应
Liuxihe reservoir
organic pollutants
ambient severity evaluation
toxicological effect
