Subway riders are inhaling toxins according to new research that examines airborne particles in metro systems across the Northeast: New York, Boston, Philadelphia, and DC. The study revealed the worst air quality can be found in New York's MTA and PATH stations. Dr. Terry Gordon, a professor at NYU-Langone's Department of Environmental Medicine and co-author of the study, told WNYC's Sean Carlson the bad air could cause serious health problems for straphangers, and especially for transit workers.

"New York City had, in general, sometimes double the amount of air pollution in the subway stations than the other cities," Gordon said.

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