Spokane Often Left Gasping Ewu Professors Find Connection Between Smoke, Inhaler Purchases

Second of two parts

Spokane is a gritty city with above-average rates of asthma and bronchitis. When the air’s bad, people rush to drugstores on weekends for asthma medicine.

That scene of a town in respiratory distress during field-burning season is described by two Eastern Washington University professors in the cover story of the June issue of the Journal of Environmental Health.

The peer-reviewed Denver journal goes to public health professionals nationwide.

EWU assistant professor Roe Roberts and chemistry professor Jeff Corkill are the Spokane study’s co-authors.

Roberts looked at the connection between field burning and emergency purchases of asthma medicine, and Corkill did a chemical analysis of grass smoke.

Among their findings:

Some 7.4 percent of Spokane residents have chronic bronchitis or emphysema compared with 6.2 percent nationwide. But Spokane has slightly fewer smokers than the national average - 23.9 percent compared with 25 percent.

Hospitalization rates for adults with asthma are higher in Spokane than the state average - 91.7 per 100,000 people compared with 86.1 statewide.

Bluegrass smoke contains harmful chemicals, including polycyclic aromatic hydrocarbons and lung-irritating phenols.

There’s a correlation between weekend purchases of bronchodilators for asthma and rising levels of air pollution during field burning in the late summer and early fall.

A leading air pollution researcher called the study “an interesting approach, but very preliminary.”

“It’s the first time I’ve seen Spokane’s lung disease rates,” said Jane Koenig of the University of Washington’s Department of Environmental Health. She is doing a long-term study of air pollution and mortality in Spokane.

“It’s useful to look at medicine use and compare Spokane’s prevalence rates with other parts of the country,” Koenig said.

The Journal of Environmental Health article was reviewed by air quality specialists at Oregon State University and the Agency for Toxic Substances and Disease Control in Atlanta, said editor Julie Collins.

Roberts and Corkill started their research after Spokane doctors petitioned the Washington Department of Ecology in early 1996 to curtail field burning for public health reasons. In April 1996, Ecology responded with a three-year plan to phase out most bluegrass burning by this summer.

The doctors said they were treating large numbers of asthma patients during grass-burning season, when clouds of smoke rolled into Spokane.

Bluegrass growers were skeptical, saying the doctors’ accounts were anecdotal. That started Roberts on her public-health sleuthing.

She used a 1995 Spokane County health department survey of 1,850 adults - the first effort here to check specific respiratory disease rates.

She compared the survey results with national statistics on respiratory disease rates in the mid-‘90s.

Roberts wasn’t able to determine an asthma rate for children because the only reliable data were for Head Start children - many of whom are at higher risk for diseases because they live in poverty.

“We had to revise the study and leave children out,” she said.

Roberts went to Group Health Northwest, a managed-care company with 160,000 members, for two years’ data on asthma-related drug purchases from the company’s pharmacy database.

The purchase patterns for four medicines were correlated with the particle levels in the air when they were purchased.

In summer and late fall when fields were burned, weekend drug purchases increased when air pollution rose. That correlation wasn’t found the rest of the year.

Meanwhile, Corkill was capturing bluegrass and wheat stubble smoke to check some growers’ assertions that grass smoke contains only harmless soot and steam.

Both types of smoke contained polyaromatic hydrocarbons, which are similar to the cancer-causing substances in tobacco. They also contained phenols.

“They are the chemicals that irritate the lung and are a short-term risk for asthmatics,” Corkill said.

These substances have been found in wood smoke, but had not been reported before in bluegrass smoke, he said.

In his literature search, Corkill found research at the University of California at Davis that measured the same compounds in smoke from wheat stubble, barley and rice.

Corkill included only his bluegrass results in the paper because he felt he didn’t have enough wheat-smoke samples. “I need to do more work on that,” he said.

Both researchers have also been participants in the field-burning controversy. Roberts has a son with cystic fibrosis and is a member of the clean-air group Save Our Summers.

Corkill is a member of the citizen’s advisory committee to the Spokane County Air Pollution Control Authority.

The authors say their study isn’t the final word on the connection between public health and field burning.

A lack of good data on lung disease rates at the local and state levels “limits the author’s ability to identify disease trends,” Roberts notes in the article.

She also says the drug purchase-pollution analysis has problems because buying an inhaler doesn’t mean it’s going to be used immediately. Many long-term asthmatics tend to stock up, and doctors sometimes premedicate sensitive patients, she said.

Also, it’s not yet known just how the fine particles in air pollution trigger respiratory problems in some people, she said.

“There’s a lot more work to be done,” Roberts said.