This article discusses the accidental impacts on humans, human food or resources-living things and wildlife caused by the release of natural and man-made chemical substances into the environment through human activities. The main reason for studying this problem is that a chemical substance may have unforeseen side effects during the production, transportation, use and disposal process, thereby posing risks to human health, well-being and comfortable environment. Society usually recognizes and evaluates potential harm to humans based on economic, social and cultural reasons. These provide the impetus for the scientific research on the impact of chemical substances on the environment. Ideally, scientists should be able to predict the possible impact of a chemical substance on humans directly or indirectly through food, crops, livestock, wildlife or climate before it is released, so as to make a more realistic cost-benefit assessment. The first approximate method for predicting potentially harmful substances may involve the following criteria: large amounts of toxic; biologically non-essential; accumulate in tissues with age; persistent in the environment; biochemical activity; storage in tissues faster than ingested It is much more harmful to some genotypes than other target species; environmental mobility in the biogeochemical cycle; does not form highly stable inert compounds in nature; the last 100 generations of target organisms increased in the environment. Regarding the impact of chemical substances on humans during their production, transportation and use, research from occupational medicine, toxicology, pharmacology, etc., as well as the impact on resource organisms from veterinary science and plant pathology to a lesser extent, A lot has been learned. Little is known about the effects of a chemical substance on wildlife after it is processed in the environment. Knowledge in this last area needs to be improved, because the ecological cycle and food chain may send potentially hazardous chemicals from affected wildlife back to humans. In addition, wild animals are often used as an indicator of the environmental status and trends of a potentially harmful substance to provide early warning of future risks to humans. We also often overlook the degree of support of wild animals to human well-being: as a food basis for important resource species (such as fishery or grazing animals); as a key species for maintaining the stability of an economically valuable ecosystem; as a predator of crop or livestock pests; As a species participating in mineral recycling or biodegradation; as an important convenience facility. Failure to recognize the interaction of people, resource species, wildlife, and climate in the biosphere, as well as their different tolerance to chemical substances, hinders the development of a unified environmental management policy that includes all four components of the biosphere. Although much is known about the effect of molecular structure on the toxicity of drugs and certain other chemicals to humans, much less is known about the effect of molecular structure on the persistence of chemicals in the environment. For wild animals, persistence may be the most important criterion for predicting potential hazards, because inevitably there will be some wild species that are sensitive to any compound and any persistent chemical substance, and are obviously harmless to a limited number of toxicity test organisms. Eventually, it will be transmitted to sensitive target species in nature through the biogeochemical cycle. This means that highly toxic, biodegradable substances are much less harmful to the environment than relatively harmless persistent chemicals, and persistent chemicals are likely to damage important wild species. The study of chemical effects in the environment can be decomposed into (a) the level of accumulation of a certain substance in the air, water, soil (including sediment) and biota (including humans), and (b) when a critical action level is reached, The impact in the biota constitutes a serious adverse reaction (ie, environmental dose-response curve). In order to predict the trend of a chemical substance level, more information about the injection rate, flow and distribution between air, water, soil and organisms is needed; and the losses caused by degradation (environmental balance sheet). These dynamic phenomena are determined by the physical and chemical properties of molecules. Fluid mechanics and meteorology may provide concepts and technical tools in the future to produce predictive models of such systems. Most of our knowledge of the impact comes from acute toxicology and medical research on humans, but because environmental impacts are usually associated with long-term exposure, more and more studies are being conducted on long-term continuous exposure to trace chemicals.