If the air in Wilmington and San Pedro seems cleaner than it used to be, it's not your imagination. The Port of Los Angeles, which released data from four harbor-area air quality monitoring stations last week, reported that diesel particulate in Wilmington in 2009 had declined 45 percent from what it was in 2006 and declined 34 percent over the same period in San Pedro.

The port has operated the air monitoring stations - one in Wilmington, one in San Pedro, and two in the port complex itself - since 2005. One of the on-port stations, located in the middle of a cargo-handling area, recorded a 48 percent drop in diesel particulate.

The decline in particulate is smaller in the community stations because the farther from the port, the smaller the percentage of the pollution that can be attributed to the port.

 - The Cunningham Report