There are numerous uncertainties associated with environmental health risk assessment (EHRA), and it is unavoidable to apply the best models and information available to save human lives. The EHRA is a method for determining the type and likelihood of adverse health effects on people who are exposed to chemicals in the workplace. To address the environmental health problems caused by harmful gas leakage and water pollution generated by the coastal regional chemical industry, a novel EHRA model for the coastal chemical industry has been developed. The premise of the Gauss plume diffusion model is used to define the model's parameters and the evaluation criterion for harmful gas concentration health risk. The EHRA model is evaluated against the leakage of harmful gases and consists of three steps. The first step is to identify the threat posed by the chemical industry in the coastal region; the second step is to quantify the risk; the third step is to develop a model for assessing water-related environmental health risk. The water-related environmental health assessor analyzes the pollutant variables and parameters of the assessment model to estimate the health risk caused by dangerous compounds in the water, using the assessment model of chemical carcinogen health risk and noncarcinogen health risk Type B. The experiments' findings suggest that the model can effectively assess the dangers to human health from hazardous gases and heavy metals in the water bodies of chemical factories in coastal communities.