An "unprecedented" toxic algae bloom has overrun the coast of Southern California, sickening marine animals and staining the shoreline amid the invasion.

A harmful algal bloom off the Southern California coast continues to sicken and kill marine life, with at least seven dolphins washing ashore this week alone in Venice Beach. Marine experts are taking samples and planning necropsies to determine if domoic acid toxicity is the cause,

California cities nearly covered all five spots in the Top 5 Most Polluted Cities when it comes to year-round particle pollution in the U.S., according to the American Lung Association.

The LA area is once again the worst for ozone in the U.S., a pollutant impacting millions more people nationwide, the American Lung Association said.

Climate change is taking a visible and increasingly toxic toll on the air Americans breathe. According to a report released by the American Lung Association, nearly half of the people living in the U.