Because of this, the South Coast Air Quality Management District issued an air quality alert through Saturday evening. It is in effect from the Santa Clarita Valley down through Los Angeles, Orange County and the Inland Empire. The fine particle pollution expelled from lit fireworks is the primary cause for the alert, as they emit high levels of PM2.5 and PM!0, as well as metal air pollutants â all of which can contribute to negative health effects, officials said.
Traditionally, the Fourth of July and days after are amongst the worst days of the year for fine particle pollution in the South Coast Basin, said a statement from SCAQMD. Because of transportation and industrial emissions throughout Southern California, there are already a high amount of fine particles present, so the smoke and combustion products even further the pollution in the area.