Where there's wildfire smoke, there's toxicity

Nov 20, 2008
Smoke from wildfires on distant inland hills pours over the ocean at Venice Beach, Calif., Nov. 16. Credit: Viterbi School of Engineering

The health threat to city dwellers posed by Southern California wildfires like those of November 2008 may have been underestimated by officials.

Detailed particulate analysis of the smoke produced by previous California wild fires indicates that the composition posed more serious potential threats to health than is generally realized, according to a new paper analyzing particulate matter (PM) from wildfires in Southern California.

The paper, entitled "Physicochemical and Toxicological Profile of Particulate Matter (PM) in Los Angeles during the October 2007 Southern California Wildfires," will appear in Environmental Science and Technology. It confirms earlier studies by air polllution specialist Constantinos Sioutas of the USC Viterbi School of Engineering, who is also co-director of the Southern California Particle Center.

For the study Sioutas and colleagues from USC, the University of Wisconsin-Madison and RIVM (the National Institute of Health and the Environment of the Netherlands) analyzed the particular matter gathered during the fall 2007 blazes.

"Fire emissions produce a significantly larger aerosol in size than typically seen in urban environments during periods affected by traffic sources, which emit mostly ultrafine particles," Sioutas said.

"Staying indoors may not provide protection from smoke particles in the absence of air conditioning or the ability to recirculate filtered indoor air. This is because the fire particles can penetrate indoor structures more readily than particles from vehicular emissions."

According to Sioutas, the fires produce a dangerous mix. "The chemical composition of particles during the fire episodes is different than that during 'normal' days impacted by traffic sources.

"Tracers of biomass burning (e.g. potassium and levoglucosan) were elevated by two-fold during the fire periodm" he said. "Water-soluble organic carbon (WSOC) was also higher during the fire event. This makes these particles from wood smoke more bioavailable, thus more readily absorbable by our system than particulate matter from traffic sources."

The ability of the particulates to penetrate structures, even if windows are closed, and their potential ability to be absorbed by human tissues are a matter of concern. "More aggressive measures to avoid smoke seem to deserve study, including distribution of masks and evacuation to air conditioned environments, and closure of non-smoke secured schools," said Sioutas, who holds the school's Fred Champion Professorship of Civil and Environmental Engineering.

Source: University of Southern California

Explore further: UN climate talks shuffle to a close in Bonn

add to favorites email to friend print save as pdf

Related Stories

Russia turns back clocks to permanent Winter Time

3 hours ago

Russia on Sunday is set to turn back its clocks to winter time permanently in a move backed by President Vladimir Putin, reversing a three-year experiment with non-stop summer time that proved highly unpopular.

UN climate talks shuffle to a close in Bonn

3 hours ago

Concern was high at a perceived lack of urgency as UN climate negotiations shuffled towards a close in Bonn on Saturday with just 14 months left to finalise a new, global pact.

Microsoft beefs up security protection in Windows 10

8 hours ago

What Microsoft users in business care deeply about—-a system architecture that supports efforts to get their work done efficiently; a work-centric menu to quickly access projects rather than weather readings ...

US official: Auto safety agency under review

20 hours ago

Transportation officials are reviewing the "safety culture" of the U.S. agency that oversees auto recalls, a senior Obama administration official said Friday. The National Highway Traffic Safety Administration has been criticized ...

Recommended for you

UN climate talks shuffle to a close in Bonn

8 hours ago

Concern was high at a perceived lack of urgency as UN climate negotiations shuffled towards a close in Bonn on Saturday with just 14 months left to finalise a new, global pact.

Study shows no lead pollution in oilsands region

Oct 24, 2014

New research from a world-renowned soil and water expert at the University of Alberta reveals that there's no atmospheric lead pollution in Alberta's oilsands region—a finding that contradicts current scientific ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

GrayMouser
5 / 5 (1) Nov 20, 2008
It's natural, how can it be toxic?