We have photochemical smog on the run!

The average level of a deadly form of air pollution dropped in the USA from 1999 to 2003 as new pollution controls made strides in battling the nation's air quality problem, the Environmental Protection Agency said Tuesday.

The deadliest form of particulate pollution, the soot emitted by tailpipes and smokestacks, fell 10% during the four-year period, the EPA reported. Particulate kills tens of thousands of people each year by triggering heart and lung problems, EPA reports have said.