In a national list of the most polluted cities in terms of year-round particle pollution Bakersfield ranks first. Visalia has tied with Los Angeles and Phoenix for second. Hanford comes in fifth and Fresno ranks sixth on the list.
The report blames vehicles, especially trucks and buses for the majority of the smog in the Valley. Wood burning is also cited as a major reason for the pollution.
The American Lung Association said that in the 11-years since the first State Of The Air report the Valley has shown significant progress in reducing pollution. The Valley has also shown significant reductions in the number of unhealthy air days.