Health Risk Assessment And Eco-toxicological Diagnosis Of Contaminated Soil Of Typical Industrial District In Nanjing City

Nanjing city, which is the capital of Jiangsu Province and one of China’s six ancient capitals, located in the Yangtze River Delta region, is comprehensive transportation hub and an important industrial production base in east of china. With the rapid development to urbanization and industrialization, the pollution problem arising from contaminated soil has become more and more serious. In this study, systematic and comprehensive health risk assessment and biological toxicity diagnosis on contaminated soil of typical industrial zone in Nanjing, which is through chemical analysis combined with ecological toxicity test, may provide the basic data and scientific basis for Environmental monitoring and and management of the Department. The main results of thispaper are as follows:(1) The monitoring of heavy metals and organic pollutants in typical industrial soil of Nanjing cityContents of heavy metals in soil of Nanjing city, which has great variability, have received interference and influence of human activities.Content of less ring number and low molecular weight aromatic hydrocarbons is relatively low; However, content of more ring number and larger molecular weight is relatively high.Polycyclic aromatic hydrocarbon mainly derived from biomass and coal combustion process.It is considered that industrial soil of Nanjing city should be concerned by environmental monitoring and management departments since total health risk of it was severely over the reference value recommended by USEPA.(2) Soil eco-toxicological diagnosisNo-observed-effect concentration and the lowest-observed-effect concentration of plant height and fresh weight introduced by Cd2+single factor stress experiments were1.124mg·L-1and5.621mg·L-1,respectively. Through the statistical analysis of the correlation between the pollution of soil and wheat toxicity effect, we found SIG value of regression equation of plant height, fresh weight, Chla, Chlb, SOD, AMS and GSH were less than0.05. These physiological indexes are sensitive to the pollution of the soil, which can be used as biomarkers to monitorbiological toxicity of contaminated soil. Multimedia environmental goals model evaluation showed that soil leaching solution of Nanjing Industrial Zone have certain harm to human health and ecological environment.(3) Health risk assessment and biological toxicity of soil leaching solutionThere are significant differences of heavy metal content among the different soil leaching solution.The ambient severity of heavy metals consistent with contents of these pollutants.Based on the risk representation model, most of the points are detected genetic toxic substances, and the risk of which are higher than the risk threshold recommended by USEPA, so industrial soil of Nanjing city should be concerned by environmental monitoring and management departments.Early seedling growth, seed germination rate can not indicate the toxicity of pollutants sensitively,while the activities of amylase and antioxidant enzyme as well as Vicia faba micronucleus, confirmed by the study, can be used as early diagnosis and early warning indicators.