The improvement in air quality comes from reductions in toxic emissions from autos, trucks, and ships. Enjoying the cleaner air were tens of thousands of Angelenos riding on miles of streets closed to auto traffic for the 10th CicLAvia event.
Risk of getting cancer from "exposure to 37 toxic pollutants—including diesel soot and arsenic," has been reduced by 65% according to a "study released by the South Coast Air Quality Management District on Oct. 2," reports Kristina Bravo of TakePart. By contrast, "(t)he last review reported a 17 percent drop between 1999 and 2005," she notes.
The greatest cancer risk from airborne emissions, 68.2 percent, comes from diesel particulate matter, as shown by Figure ES-3 in the report [PDF] and as explained by environmental reporter Tony Barboza of the Los Angeles Times.
Diesel exhaust remains the largest contributor to the problem, the air district's analysis found, and is responsible for more than two-thirds of all air pollution cancer risk in the region. About 90% of the risk comes from mobile sources, including cars, trucks, cargo ships, locomotives and airplanes.
Notwithstanding the pollutant reductions, Bravo reminds us that "compared with the rest of the nation, Southern California is still among the worst places to breathe."
However, Angelenos did breathe easier on Sunday, October 02, particularly those enjoying streets with no auto traffic thanks to the tenth CicLAvia event, which Bravo covers in a separate piece. She speaks with Jonathan Parfrey, "vice chair of the CicLAvia Board of Directors and the executive director of Climate Resolve, an organization that pushes for climate change action in the city."
FULL STORY: The Air in Southern California Just Got a Whole Lot Cleaner

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