Construction Workers Toil Away in San Francisco's Toxic Air

From where Trina Hill is stationed at the corner of 16th and Illinois streets, she can see the future of San Francisco rising all around her. This is the Mission Bay neighborhood, the new hotbed for science, tech, and medicine. Warriors Stadium is right across 16th. Behind her stands the building she and her coworkers are finishing, future research laboratories for the University of California at San Francisco—one of the leading medical research institutions in the world.