摘要
以人工污染土壤为介质,荧蒽为供试化学品,以蚯蚓内脏中细胞色素P450含量、谷胱甘肽转移酶(GST)、超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性和丙二醛(MDA)含量为指标,进行了不同暴露时间(1、3、7和14d)下低剂量荧蒽(60、120、240、480和960μg kg-1)污染胁迫对蚯蚓(Eiseniafetida)的毒性效应研究。结果表明,在供试浓度范围内,蚯蚓内脏中各生化酶系产生了不同程度的响应。其中P450含量、SOD和POD活性比较敏感;而GST和CAT活性,以及MDA含量在供试浓度范围内对荧蒽的暴露没有明显的指示作用。研究发现,低剂量污染物暴露的时间效应较剂量效应更有指示作用,并且生物体内各生化酶系对污染物暴露的敏感性存在差异,因而在土壤污染生态毒性诊断时,选择多时段检测和多指标联合诊断,对污染暴露指示的有效性和敏感性尤为重要。
Biochemical responses of earthworm （Eisenia fetida） to fluoranthene were studied and cited as biomarkers for monitoring PAHs-contamination of sublethal concentration in the soil. Earthworms were exposed to soils contaminated with different concentrations of fluoranthene （60, 120, 240, 480, 960 μg kg^-1 and CK）. After exposure for 1, 3, 7 and 14 days, earthworms were collected for analysis of contents of total cytochrome P450 and MDA and the activities of glutathione-S-transferase （GST）, superoxide dismntase （SOD）, peroxidase （POD） and catalase （CAT） in the guts. Results indicate that within the range of concentrations in the test, fluoranthene triggered varying responses from biochemical enzymes in the guts of the earthworms, particularly from P450 in content, and from SOD and POD in activity but not as significantly from GST, CAT and MDA. The research also revealed that the effect of duration of the exposure was stronger than that of dosage limited within the range of sublethal concentrations on the biochemical responses. As biochemical sensitivity to the pollutant varies from enzyme to enzyme, it is necessary to use a combined multi-time multi-index diagnostic method in diagnosing ecotoxicity of the pollutant in soil, with special stress on sensitivity and effectiveness of the indicators of exposure to the pollutant.
出处
《土壤学报》
CAS
CSCD
北大核心
2007年第6期1049-1057,共9页
Acta Pedologica Sinica
基金
国家重点基础研究发展规划(973)项目(2004CB418503)
国家自然科学基金项目(20337010和20577056)
国家高技术研究发展计划(863)项目(2006AA06Z386)资助
