Sure, we know that taking public transport is easier on our eco-footprint, but is the air down in the Paris métro safe to breathe? Ecologie sans frontiere, a French NGO, issued a study earlier this month warning that air pollution in the greater Paris region is woefully under-reported and that the metro and airports in particular are aggregators of toxic particulates which are not regulated by appropriate legal norms.
Official surveys of air quality in Paris have consistently shown improvements in the past decade but the NGO warns that this is because they focus exclusively on pollutants that been on the wane because of improved car technology, like sulfur dioxide and benzene. Ultrafine particles are dangerous because they are extremely easy to inhale, and particulate pollution has been linked with respiratory and heart disease, as well as poor lung development in children. ESF wants every metro station in Paris to display pollution levels and to carry warnings to users on the health risks which these levels represent.
The Paris transport authority (RATP) came back with its own study published last week, in which it maintained that the air in the metro was more or less the same as the air outside (how reassuring is that?) – with a bit less ozone and a bit more dust and metal particulates.
Based on air samples taken at five métro stations, the study found 300 micrograms per cubic meter over a two-hour period, and much higher levels in the suburban RER stations such as Auber. RATP claims that the results are roughly in line with pollution levels in the Stockholm underground, and slightly better than those in London, where the depth of the underground and long tunnels fosters stagnation. The RATP currently uses a safety threshold of 347 micrograms per cubic meter over a two-hour period.