It was just on November 21 that Wildfire Today covered a new study about the effects of smoke on wildland firefighters. Now another new study on the emissions from wildland fires provides more data on the particulates produced by the fires and how they affect the public. Some of the findings include:
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.
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.
The study’s recommendation about the “distribution of masks” is questionable, in light of other data reported by Wildfire Today. If they are referring to the cheap, disposable dust masks, the information we have seen (below) indicates that they cannot remove the small particulates in wildland fire smoke.
The substances of greatest concern are carbon monoxide, formaldehyde, acrolein, and respirable and inhalable particles. A second group of concern, but present at proportionally lower concentrations, includes benzene, carbon dioxide (CO2), nitrogen oxides, PAH, ammonia, and furfural. A third group of concern, but present at proportionally lower concentrations again, includes acetaldehyde, 1,3-butadiene, methane, methanol, styrene, acetonitrile, propionaldehyde, toluene, methyl bromide, methylethylketone, acetone, methyl chloride, xylenes, phenol, tetrahydrofuran, methyl iodide, and mercury. Data suggests that if wildland firefighters are exposed to 25 ppm of carbon monoxide (below the permissible exposure value), they may be overexposed to formaldehyde, acrolein, PAH (benzo[a]pyrene), and respirable particles.
The U.S. National Fire Protection Association has recently announced that it is proceeding with the development of a new wildland firefighting respiratory protection Standard, but it will be some time still before respirators certified for wildland firefighting will become available.
If administrative controls are unsuccessful in reducing exposures to acceptable levels, wildland firefighters should be provided with air purifying respirators for formaldehyde, respirable particulate matter, organic vapours and acids, acrolein, and PAH. However, wildland firefighters should be cautioned that at high work levels the effectiveness and duration of air purifying cartridges is unknown. There is also a concern that firefighters using air purifying respirators may unknowingly expose themselves to higher levels of contaminants not removed by their respirator than they would otherwise. Until a respirator is developed for wildland firefighting that effectively removes carbon monoxide, air purifying respirators should be used in conjunction with a carbon monoxide alarm.
Like “a mosquito through an open door”.
Firefighters, especially new ones, frequently ask if bandannas over the face will protect them from smoke. The answer is hell no.
“Respirable smoke particles, gases, and vapours would pass through a bandanna as readily as a mosquito thorugh an open door.”
Click on the image above to see a larger version.
In fact, even respirators, as inconvenient as they are, will not do the job according to the report.
None of the filtering respirators remove carbon monoxide (CO). All of the currently available respirators have serious shortcomings for use in a wildland fire situation. Even if they were effective, some wildland firefighters are understandably reluctant to accept negative pressure air purifying face masks for use at high work levels for long periods of time.
A full face mask is generally more comfortable than a half-face mask and it provides full eye protection. Full eye protection is necessary the case of contaminants exceeding the threshold limit value where the threshold limit value is based on irritant effects.
Since the contaminants having warning properties such as odour or irritant effects are removed by air purifying respirators, there is a legitimate concern that firefighters wearing such respirators might unknowingly expose themselves to higher levels of toxic contaminants not removed by the respirator than they would otherwise. This could easily result in over exposure to carbon monoxide and lead to serious, perhaps deadly, consequences. To avoid this, a carbon monoxide monitor with alarm should be used in conjunction with air purifying respirators used when fighting wildland fires.
So, forget about the bandanna, and throw away that $84 piece of crap Hot Shield mask that is advertised to have the “ benefit of blocking & reducing the inhalation of smoke & ash particulate”. These smoke particulates are so small, that if one were released near the ceiling in a room with calm air, it would take eight hours to fall to the floor.
The sad truth is, in 2008 there is no practical way to protect wildland firefighters from the byproducts of combustion. Maybe the new 8-pound SCBA being developed will lead to something that could benefit wildland firefighters. Using this new technology, perhaps a 15-pound unit would give you an hour’s worth of air? This might help for initial attack, but for the hot shot crew on the line for 16 hours, sorry, you’re out of luck.
We are not aware of any specific study that has been completed on the occurrence of cancer among wildland firefighters, but there is enough data out there about structural firefighters that make this a major concern. Wildfire Today has covered this before, but the Spokane Spokesman-Review has a new disturbing article about a local cancer cluster. Here is an excerpt.
Doug Bacon missed the funeral of a fellow Spokane firefighter because the 59-year-old was in treatment for throat cancer – the same illness that had just killed his friend and co-worker.
A third Spokane firefighter who joined the department with Bacon in the 1970s also has been diagnosed with throat cancer.
“It’s to the point we’re trying to figure out which fire we were all on together,” said Bacon, who survived his cancer and returned to the job in mid-2006. “I’ve got attitude. I fought it.”
Firefighters are at least twice as likely to get cancer as the average person because of exposure to toxins emitted in fires, such as benzene, asbestos and cyanide, studies say. More firefighters have been diagnosed with cancer in the past two years than in the previous 10 years, according to the Firefighter Cancer Support Network and recent studies.
When Bacon was diagnosed with cancer in January 2006, he said he just looked at the doctor and said: “You’re kidding me.” He was unaware at the time that firefighters were more susceptible to the disease. Now, he’s constantly warning young firefighters of the dangers and telling them to keep their masks on – even after the fire’s out.
During July, Spokane area firefighters fought blazes nearly every day, including the massive Valley View wildfire, and two three-alarm fires – The Ugly Duck and Joel building.
Despite wearing protective gear, some walked away from those blazes hacking and coughing. Authorities say asbestos – a cancer-causing agent often found in old building materials – was found in the Joel building.
Research is still being done to determine what level of exposure leads to cancer in firefighters, officials say. Meanwhile, the illness has become a primary concern for the profession.
“Finally we are taking our blinders off when it comes to cancer,” said Michael Dubron, founder and president of the Firefighter Cancer Support Network. Dubron is a cancer survivor and Los Angles firefighter. “With our organization, we are trying to be proactive, such as reducing unnecessary exposure. No longer is it cool to run around with soot-covered uniforms and equipment.”
The soot contains many of the same toxins firefighters are exposed to during a blaze, officials say.
In Canada, the British Columbia government recognizes as an occupational hazard for firefighters the following diseases:
lung cancer in non-smokers
This means that full-time, volunteer, part-time, and paid on-call firefighters suffering from the diseases will qualify for worker’s compensation and benefits, without having to prove individually that the diseases are linked to their jobs.
There is not a lot that wildland firefighters can do to avoid breathing the byproducts of combustion. There is no such thing as a breathing apparatus containing clean air that can be carried for a 16-hour shift.
The various filter masks that are sometimes bought by wildland firefighters do nothing except filter out some of the larger particles, sticks, and rocks. The microscopic smoke particulates are so small, that if one were near the ceiling in a room with still air, it would take about eight hours to fall to the floor. And the masks do nothing to remove the various toxic gasses and other contaminates.
We need to establish a system to track the long term health and cancer occurence within the wildland firefighter community.
There is so much smoke from so many sources that it is becoming difficult to determine the origin. Today’s smoke map generated by NOAA is very different from the one yesterday. The visibility here in South Dakota is about two miles due to smoke. I just talked with someone in Billings, MT and he said it is about the same there.
So you tell me. Is the smoke in South Dakota coming from the fires in California, or Canada? It seems unlikely it could be coming from both, as the map seems to indicate. Maybe the California smoke is blown to the north occasionally, then later a west wind blows that plume to the east.
On June 28 we posted a map that showed smoke plumes from California reaching east all the way to Missouri. Today there is even more smoke across the U.S. but most of it is not from the California fires. It originates in Canada, California, Kansas, Oklahoma, Arkansas, and Mississippi.
On the map below, the red dots are fires and the gray areas are smoke.