Ultrafine particles prevalent in London Underground air pollution

Ultrafine magnetic iron oxide particles smaller than 500 nanometers are prevalent in air pollution on the London Underground, according to a study published in Scientific Reports. The authors propose that improved air pollution monitoring—which measures the magnetic properties of particles— and efforts to further reduce air pollution levels may be needed on the London Underground. Previous studies have identified associations between exposure to ultrafine particles and a range of health conditions—including asthma and cardiovascular diseases.