In recent years, the public has become increasingly aware of the presence of harmful chemicals in our environment. Many people express concerns about pesticides and other foreign substances in food, contaminants in drinking water, and toxic pollutants in the air. Public's physique is getting worse. because of the poor living environment. How do we, as a society, decide where to focus our efforts and resources to control these hazards of ourslves? When we feel not very well, such as weakness ,tired without any reasons ,insomnia and dreaminess,what should we do?
Health risk appraisal is a scientific tool designed to help answer these questions. Risk appraisals can also guide sub-health people in disease prevention. The purpose of HRA is to provide a basic explanation of risk assessment for people involved in body health issues,including policymakers, businesspeople, members of community groups, news reporters, and others with an interest in the potential health effects of toxic chemicals。