Following the Sept. 11, 2001, attacks on the World Trade Center and the Pentagon, many experts have become more concerned that terrorists may maliciously spread biological agents such as anthrax or smallpox.
While petrochemical plants get the most attention, statistics from the Chemical Safety Board suggest that media overlook three quite common and widespread hazards: chlorine, ammonia, and propane
There are places along the Mississippi River (e.g. New Orleans) where many people live in areas that would normally be flooded, were it not for levees or other flood control works.