From the burning of fossil fuels, mostly power stations.
Highest levels found close to road traffic or indoor gas cookers.
Caused by chemical reactions between natural, traffic and industrial pollution in strong sunlight.
Solid particles or liquid droplets in the air, primarily from road traffic. When smaller than 2.5 micrometers (that’s 60 times thinner than a human hair), they are known as PM2.5. Larger particles, which could be dirt or dust stirred up from vehicles are known as PM10.
Less of a problem in some countries due to controls on emissions. Iron and steel sectors dominate lead emissions, while disposal of treated wood by burning is source of arsenic.
These health impacts have all been linked to the main pollutants
Suppresses normal lung growth in children. Accelerates lung function decline or an ageing lung in adults and a known cause of lung cancer. Also linked to onset of asthma.
Linked to onset of type 2 diabetes in adults.
Linked to the development of cardiovascular diseases, such as a stroke and heart disease, including atherosclerosis (furring of the arteries). Can also exacerbate existing conditions.
Exposure of pregnant women found to affect to fetal brain growth. Also impacts mental and physical development in children and cognition in adults.