The Bay Bridge is obscured as smoke from the Camp Fire fills the air in San Francisco, California, U.S. (Photographer: Michael Short/Bloomberg)

‘Insane’ California Air Topped World Health Standard by 60 Times

(Bloomberg) -- California’s air exceeded world health standards by 60 times last week, and conditions on Monday continued to top safe thresholds with the deadliest blaze ever in the state is about 65 percent contained.

Last week, particulates in the air reached as high as 1,500 micrograms per cubic meter. The threshold set by the World Health Organization is 25. Lower levels on Monday still exceeded the benchmark.

“It is just insane,” said Rebecca Buchholz, a project scientist, who studies pollution from fires at the National Center for Atmospheric Research in Boulder, Colorado. “It is quite amazing how high these fine-particulate levels are.”

The Camp Fire blaze in Butte County, California, has killed at least 77 people, destroyed 10,623 homes and consumed 150,000 acres, according to Cal Fire. The blaze will probably be extinguished by Nov. 30.

The smoke has drifted far south. On Monday, Sacramento’s air was listed as unhealthy and particulates reached a level of 135.4 micrograms per cubic meter, according to the U.S. Forest Service. San Francisco has a reading of 55 with San Jose at 76.1 and Stockton at 152.

The particulates can irritate lungs, eyes and nasal passages and are particularly dangerous for people with respiratory diseases, Buchholz said. In addition to the smoke, fires cause ground-level ozone to form, triggering more-severe health issues.

Heavy rain is forecast on Nov. 21, raising the risk for mudslides because trees and brush have been lost. The poor air quality won’t just end when the fires go out, Buchholz said.

Smoldering will keep smoke in the air, and without the heat of an active fire to push particles into the atmosphere, they will linger near the ground, she said.

©2018 Bloomberg L.P.