BOULDER, Colo., April 26 (UPI) -- The microbial population in the air of the New York subway system is nearly identical to that of ambient air on the city streets, researchers say.
The results "are strong testimony for the efficiency of the train pumping system for ventilation," principal investigator Norman R. Pace of the University of Colorado, Boulder, said in a statement. "I was impressed by the similarity of subway and outdoor air."