`` Smog-eating tiles '' can oxidize the smog-forming nitrogen oxides released in the air . Comment: Read more : Ancient 'air-conditioning ' cools building sustainably . Experts warn air pollution poses a serious threat to the health of city dwellers . Los Angeles has the highest levels of ozone pollution in the United States .
`` Smog-eating tiles '' can oxidize the smog-forming nitrogen oxides released in the air . Comment: Experts warn air pollution poses a serious threat to the health of city dwellers . Los Angeles has the highest levels of ozone pollution in the United States .