Adverse Outcome Pathways (AOPs) are scientific frameworks used to understand how harmful substances in the environment, such as chemicals and pollutants, can lead to health problems. By mapping the sequence of events that starts with exposure to a pollutant and leads to an adverse health effect, AOPs help scientists and policymakers see the "big picture" of how certain environmental chemicals might harm people’s health. For example, AOPs can show how air pollution may trigger biological changes that lead to respiratory issues like asthma or cardiovascular diseases. This knowledge aids in developing better safety measures and policies to protect public health from environmental hazards.