Air pollution can be man-made, such as fumes from cars and smoke from burning fuels like wood or coal. Both indoor and outdoor air pollutants have been shown to increase the risk of cancer. Air pollution is associated with an increased risk of lung cancer.
Air pollution from dust, smoke, and other chemicals in the atmosphere has been attributed to cause ~ 2% of lung cancers in the US. Compounds in the pollutant could lead to DNA damage in the lungs which set the stage for a higher risk of lung cancer. Indeed the The IARC has classified outdoor air pollution as a cancer-causing agent. Find link below for your perusal.
The fact is that IARC has evaluated what we commonly call air pollution in two components as carcinogens. The overall air pollution as one component as well as outdoor particulate matters in the air (substances smaller than 2.5 micrometer) are declared as Group 1 carcinogens.