The Assessment Index System For Human Vulnerability Of Health Risk Caused By Heavy Metal Pollution:A Case Study

Environmental pollution accidents happen frequently in China in the latest years, resulting in huge damage to public properties and human health. However, the protection' of public is so weak that it can decrease people's vulnerability of environmental risk by neither improving the environmental situation people living in nor enhancing people's resistance of risks. The emergency management is not effective because the distribution of vulnerable targets is not clear. While public demand for environmental quality improvement and the self-protection consciousness are increasing in recent years, leading to frequent group affairs and social unrest. Therefore, in the view of human receptor of environmental risk, it is significant to study on the public vulnerability and identify the vulnerable targets in the risky region.Due to multiple risk sources and exposure routes, the heavy metal pollution has caused serious damage to human health. So it is necessary to improve the assessment index system, which is applied to evaluate the level of public exposure, risk sensitivity, resistance, and identify the influencing factors of vulnerability to help making valid risk management strategy. Thus, in this study, we create a multi-dimension index system for human vulnerability assessment, including the environmental exposure, social economic, human exposure behavior, and risk perception, which would be quantitively examined by structural equation model.We selected some different villages around mining area in Nanjing and Suzhou and four investigation of five critical heavy metal (Cd, Cr, Pb, Zn, Hg) were conducted to collect data, including the detection of heavy metal concentration in environmental media, collection of residents' hair to measure the inside-exposure, residents'behavior survey in daily life, and investigation of public risk perception. Base on these data, we finally fixed the index system by quantitively tests and modification. Besides, we also proved that the increase of environmental exposure and residents exposure behavior would strengthen people's vulnerability, while the increase of social economical level and public risk perception would reduce people's vulnerability to heavy metal pollution.According to the results of regional vulnerability assessment using the index system we created, vulnerable regions were recognized. The nearest village to mining area in Nanjing were "highly polluted and highly sensitive" place, while the area around new and old mining sites were "highly/moderate polluted but lightly sensitive" places. Accordingly, we should emphazise on pollution reduce, and also take physical examination for the residents to find out the health problem in time, besides, strengthening risk communication and public participation was also important to avoid the group affairs in "high-high" area. We should conducted strict management of risk sources, and also increase environmental health education in the "high-low" area at the same time, which may be helpful to increase the self-protection conscious and avoiding health problems of residents in daily life. Over all, we defined different regions in risk management. Different strategies should be applied in different areas, which could realize the mode transformation of risk receptor management from "end-emergency response" to "preventative protection".According to the results of relationship analysis between individual vulnerability and other influencing factors, the vulnerable residents around minning areas were recognized, which included the workers, residents living nearby the mineral spot, residents living in polluted air, female, smokers from objective view, and residents of low-education, farmers, jobless residents from the subjective view. Due to the situation of serious population aging, low income and education level in the studies areas, the education level became the most important influencing factors of people's risk perception, majority of resident regard the heavy metal risk as unknown, serious, incontrol risk, and the acceptability was different in different village. These results can provide more specific targets for environmental-health protection as well as local environmental risk management.