The words "health and environmental hazard" imply dangers and risks that can harm both human health and the environment. Some synonymous phrases include "toxic threat", "dangerous pollutant", "harmful substance", "unsafe chemical", and "environmental risk". These words are often used to describe substances like pesticides, fossil fuels, and industrial chemicals that can contaminate air, water, soil and food. It is important to identify and mitigate these hazards, as they can have serious impacts on human and ecological well-being. By using caution and working to reduce exposure to harmful substances, we can protect both our health and the environment.