The Air we Breathe
Los Angeles is the number one city polluted by ozone, according to the American Lung Association’s 2019 census which gave the city an F rating.
NASA defines Ozone as a naturally occuring gas that forms in the upper part of the atmosphere, formed when oxygen atoms (O2) are split by sunlight and then combined into O3.
As part of the stratosphere, Ozone is considered good as it protects against ultraviolet radiation from the sun. But when it interacts with nitrogen oxide gasses from car and industrial emissions, it can cause ground-level ozone, which has dangerous effects. NASA states that anything over 70 parts per billion (ppb) per 8-hours is considered unhealthy.
“Low level ozone, if it can manifest, has irritation and then you can, lets say, you have asthma or some kind of respiratory issue that is chronic, [ozone] can make that worse,” says Santa Monica College Professor and Life Sciences Department Chair, Alexandra Towers.
As of May 7, 2019, Los Angeles has reached around 0.072 parts per million (ppm) per 8-hours. In comparison to last year at the same time, this is continuing the trend. In 2018, Los Angeles reached a high of 0.099 ppm for the daily 8-hour Ozone concentration in the month of September.
To put those numbers in perspective,0.072 ppm is equal to 72 ppb, which is a little larger than the recommended healthy amount.
“It's far and away above the concentrations that station agencies have suggested,” says Towers.
Towers explains how pollution in various parts of the world will vary in particulates and effects. “What we experience in California is different from that which they experience in Pennsylvania. For example, because of the different climates or what they're using to burn a lot of coal is burned in the east and because of the way that movement travels, it carries the same kind of the emissions.”
Los Angeles ranked in at least the top ten of all of the American Lung Association reports, which measured things such as short-term particle pollution and year-round particle pollution. California cities such as Bakersfield and Fresno also numbered among the top polluters.
Particle pollution, or particulate matter, is a mixture of small liquids and solids floating throughout the air. Such particulates include beach sand, dust, metals, and pollen. The difference in these two lists is that one is representative of a 24-hour period, and the other represents the year-round stretch.
NASA scientists agree that climate change contributes to ozone pollution; if trends continue, Los Angeles can expect ozone pollution to continue to rise in the coming years.