Wildfires, air quality and your health - Part 1

NEVADA CITY, Calif. - "It's not a question of if, just a question of when the next catastrophic wildfire will occur." That's the mantra of firefighters, scientists and anyone living in the Wildland-Urban Interface (WUI) in the Sierra Nevada. The wildland-urban interface (WUI) is the area where houses meet or intermingle with undeveloped wildland vegetation.

Historically, wildfires were part of the ecosystem and provided for natural thinning of the fuel load in the Sierra. With an expanding population came the need to protect lives and homes from catastrophic wildfires, resulting in massive suppression efforts.

In 1933, the Civilian Conservation Corps (CCC), a work program established by President Roosevelt, started building an 800-mile long fire break through the Sierra Nevada. Known as the Ponderosa Way, remnants of the fuel break can still be found in many counties.

According to the California Department of Fire and Forestry Protection (now CAL FIRE), "The firebreak was intended to be a permanent defensive line between the lower foothill regions and the higher elevation National Forest lands." At the time, the fuel break was created to protect timber from human-caused fires. Times have changed drastically.

Low fuel moisture, high temperatures and human impacts in the WUI now combine into the ideal conditions for fast-moving fires. At the same time, air pollution levels regularly approach unhealthy levels, according to the air quality monitoring agencies in the Sierra Nevada. Coincidence? Hardly.

During the 2008 lightning storm, thousands of wildfires burned throughout the state, clouding the skies and making outdoor activities hazardous to anyone's health. The July 12, 2008 Air Quality Advisory for Butte County read in part: "Paradise: The 24-hour average in Paradise yesterday was 204 ug/m3 which is equal to an AQI of 254 Very Unhealthy). Today the AQI in Paradise is forecast to reach 210. At this level the air quality is rated VERY UNHEALTHY FOR ALL PEOPLE."

An AQI value between 0 and 50 is considered Good, according to the U.S. EPA and their partners.

Up and down the state, air districts issued daily warnings, urging people to restrict any outdoor activity. Schools canceled sports practice in many cases, putting their students' health first.

In an unprecedented move, some of the air districts urged people identified as belonging to sensitive groups, like seniors, small children or people with respiratory illnesses to leave their homes. The Northern Sierra Air Quality Management District (NSAQMD) recommended the at-risk groups leave the area, inviting them to, if necessary, seek refuge with friends and family in unaffected areas.

At the end of this "Lost Summer in the Sierra," exhausted firefighters had won the battle against the wildfires, but the consequences and lessons learned from this event are still bearing fruit.

The Fire Chief for the Tahoe National Forest and Interagency Incident Commander Jeanne Pincha-Tulley explained during a townhall forum in July how firefighters deal with exposure to smoke. "We learned a lot over the years and we're trying to minimize health risks to our firefighters. Our fire camps take into account the need for clean air (as much as possible.) If needs be, we send them to locations where they can not only rest, but clear their lungs out after spending time fighting a fire," Pincha-Tulley said.

She added that while control burns during the winter season produce a certain amount of smoke, "prescribed burns are an important tool to reintroduce fire in the ecosystem and reduce fuel loads." Prescribed fires are only ignited if all the conditions are right - changes in weather have prompted burns to be canceled or terminated earlier than planned.

Pincha-Tulley also commented on the unusual layer of smoke during the 2008 lightning storm, saying "Actually, if we had had normal weather patterns, with the coastal breeze blowing and adding more oxygen to the fires, the damage would have been much greater. It was very unusual but very lucky to have the smoke sit on top of the fires."

Local Firesafe Councils work with homeowners in the WUI to manage the fuel load on their properties. Many communities have access to free or low-cost chipping programs, free inspections and advice on how to prepare for and survive wildfires. For a list of Firesafe Councils in California, visit the state Firesafe Council website.

Where There's Smoke, There's Pollution

While locals remember the poor air quality and eerie sunsets, agencies and medical professionals have implemented new tools designed to minimize exposure to the noxious fumes.

"2008 was a paradigm shift for air districts," says Ann Hobbs, spokesperson for the Placer County Air District. The Sierra Nevada air districts now have an extended monitoring network, with real-time data available to the public via the California Air Resources Board's website.

In 2008, much of the monitoring equipment failed, due to overload by fine particulate matter, according to reports by the air quality districts.

Gretchen Bennitt, the head of the Northern Sierra Air Quality Management District (NSAQMD) vividly recalls her team's efforts to keep the monitors going and provide the best possible info to the public and the State Air Resources Board. "Telling people to leave their home and basically evacuate for health reasons during a wildfire was unheard of. Now, we consider it a public safety tool," Bennitt said. "We also recommend running your air conditioner if you have one and set it to recirculate only. Also, get a good HEPA filter for your air conditioner."

Bennitt urged caution when wearing respiratory masks. "It's a big concern for us. Because if you wear the wrong mask or wear it the wrong way, it could make you sicker." She urged people to visit the CARPA website for information on choosing the right mask.

She and her colleagues discussed the impacts of large-scale air pollution from wildfires in 2010 at the California Air Response Planning Alliance (CARPA) conference.

Medical Professionals

Dr. Roger Hicks is the head of Yuba Docs Urgent Care in Grass Valley, CA. Dr. Hicks is Board Certified in Emergency Medicine, and is a member of the Urgent Care Association of America. His practice saw a definite increase in respiratory illnesses during the 2008 firestorm.

Wood smoke is frequently associated with visits to the emergency care facility, says Linda Rachmel, R.N., the Practice Manager for Yuba Docs. "Even during winter time, smoke from wood stoves can impair people's breathing," Rachmel said.

The inversion layer created by the 2008 fires was very similar to the seasonal inversion layer during winter, with smoke settling in valleys and lower elevation locations throughout the Sierra.

New Studies Confirm Health Impacts of Smoke

In the May 2011 Fire Science Brief, Dr. Andrzej Bytnerowicz Senior Scientist at the Forest Service Pacific Southwest Research Station notes, "Particulate matter seems to be the most important pollutant from the human health point of view. Ozone and nitrogen oxides could also affect human health."

His research focused on the impacts of fire on air pollution, with special attention to emissions by wildfires.

An air pollution study by a California State University, Fresno institute indicates that as ozone and fine particulates in central San Joaquin Valley air increase, so do rates of children's asthma emergency-room visits and hospitalizations.

More wildfire pictures can be found in our Fire Gallery and on tumblr.