Underground Railway Stations May Compromise Health

Underground railway stations are known to have elevated particulate matter (PM) loads compared to ambient air. These particles are a health concern because they have the capacity to catalyze the generation of reactive oxygen species (ROS).  Matthew Loxham, from the University of Southampton (United Kingdom), and colleagues report that these particles are derived from metal-rich sources and transition metals – much like airborne iron, copper and nickel found at steel mills and welding plants.  The team found that the ultrafine dust in underground railway stations was at least as rich in metals as the larger dust particles have an increased surface area to volume ratio, and are able to penetrate the lungs and the body more easily, posing potential health hazards to those working and travelling in the underground. There is evidence that this ultrafine dust may be able to evade the protective barrier lining the airways (the epithelium), and enter underlying tissue and the circulation, meaning that the toxicity of ultrafine particles may not be limited to the airways but may involve the cardiovascular system, liver, brain, and kidneys.