Scientists have linked air pollution with many health conditions including asthma, heart disease, lung cancer and premature death. Among air pollutants, fine particulate matter is especially harmful because the tiny particles (diameter of 2.5 μm or less) can penetrate deep within the lungs. Now, researchers have integrated data from multiple sources to determine the personal exposure of people in peri-urban India to fine particulate matter. They report their results in ACS' Environmental Science & Technology.