Communities in Downtown Los Angeles and East LA have some of the worst air in the state, and LA as a whole doesn't meet national standards for air quality, in part because of the volume of traffic that fills the streets and freeways, and the car-produced junk that gets into the air as a result. So it makes sense, then, that when some of that traffic disappears—even just for a day—it would have an impact on the freshness of the air. A new study from UCLA's Fielding School of Public Health has found that CicLAvia, the wildly popular event that shuts down a few miles of streets to cars and opens them up to people for one day every few months, "significantly reduces air pollution along the CicLAvia route" and even on adjacent streets in neighborhoods that host the route, says a release from UCLA.
The study, which appears in the journal Environmental Pollution, sampled air quality in a period leading up to, during, and after the October 2014 CicLAvia, which ran through East LA, Boyle Heights, Chinatown, and Echo Park. Researchers went out and took readings on the Sunday before and the Sunday after the event, as well as on the day of the CicLAvia. On each day, they measured traffic volume and air quality in the morning, around noon, and later in the afternoon, the scientists write in the study.
In the air along streets that were closed to car traffic for the event, there was a 21 percent drop in ultrafine particles (associated with an increased risk for respiratory and cardiovascular disease) and a 49 percent drop in particulate matter, which has also been linked to respiratory and heart disease, as well as lung cancer and premature death.
Such a marked decrease in nasty pollutants is great, but the study also found that streets in the area that were not closed to cars, but still close to the route, saw a 12 percent lower reading of particulate matter in the air on the day of the event than on non-CicLAvia days. Meaning that the air that people on and around the route are breathing is less polluted by these two major contaminants than the air they'd normally be breathing in if they were in the same exact place on any other day.
That's really good news for people who are biking, says one researcher, "because their respiration rates were much higher than that of the pedestrians." And that's also great news for the communities that CicLAvia passes through. The authors of the study agree that three days of information isn't enough to "accurately gauge" the effect that CicLAvia has on air quality in the neighborhoods it passes through, but also say that their findings suggest that further research on just how much the event does to alleviate air pollution should be done.
· L.A.'s CicLAvia significantly improves air quality in host neighborhoods, UCLA study finds [UCLA Newsroom]
· CicLAvia [Curbed LA]
· Carmageddon I Improved Air Quality Immediately and by 83% [Curbed LA]