A new study has revealed alarming statistics on the state of air pollution in major cities across the world. Data collected from 50 cities shows that 80% of urban areas exceed the World Health Organization's recommended limits for air quality. It was found that over 9 million people die each year due to exposure to poor air quality, with 80% of these deaths occurring in low- and middle-income countries. The study highlights the urgent need for policymakers to take action to address this global public health crisis.