Out of thin air

For decades, UCI chemistry professor Donald Blake, M.S. ’80, Ph.D. ’84 has been admired for his work with Nobel laureate F. Sherwood Rowland on air pollution, global warming and climate change. Recently, Blake found an extraordinary new benefit of his research: the noninvasive diagnosis of life-threatening diseases such as cystic fibrosis. UCi magazine talked with Blake about how this revelation came about and its implications for improved health care.

What made you first suspect that the method you use for measuring air pollution could detect cystic fibrosis?

It was luck. Five years ago, I got a call from Dr. Dan Cooper, program director of UCI’s General Clinical Research Center, which conducts patient-oriented research. He was looking for someone to do a breath-gas analysis for people with various health problems. Breath is one way the body gets rid of stuff it doesn’t need, like carbon dioxide. So, it’s not a big leap for us to test the breath for other gases.

How was the CF study conducted?

Michael Kamboures, a graduate student in our lab, collected breath samples from about 20 people with CF and 20 without the disease. Samples are collected into evacuated two-liter stainless steel canisters. You just open a valve and blow into the canister; it’s about as noninvasive as you can get. We also collected room control samples to determine which gases were given off by the person, and which were inhaled from the atmosphere.

What did the study show?

We measured 71 gases, all of which we routinely measure in the atmosphere. One was carbonyl sulfide. We discovered people with CF breathe out more carbonyl sulfide than people who don’t have the disease. In some cases, they breathe out more than they breathe in. It’s a good marker for CF. The worse the lung function, the more the patients give off carbonyl sulfide.

What do the findings suggest for people with CF? Does breath analysis offer hope for treatment?

Our study suggests that bacteria colonizing in the lungs of CF patients give off carbonyl sulfide. Two graduate students are testing eight of those known bacteria to see if they give off different concentrations of gases – or an individual fingerprint. If doctors can identify specific bacteria in their patients’ lungs using breath-gas analysis, they might be able to design or prescribe antibiotics that kill it instead of prescribing a broad spectrum antibiotic. That’s exciting, because it would mean better treatment for patients.

What are some other clinical possibilities of the test?

We’ve cast a wide net with breath-analysis testing. We’re working to come up with markers for pneumonia, diabetes and other diseases. We’ll begin working on a study that would show whether someone has been exposed to selected biological agents. And we’re participating in a study of premature infants, to identify those who need antibiotics to ward off life-threatening infections.

What other research projects are you and Professor Rowland involved in?

We’re studying the atmosphere in Mexico City, Antarctica, Iraq, and even dairy farms in California’s Central Valley. We have a lot going on all the time because of our reputation for measuring gases accurately and precisely. But it’s the breath stuff that excites us the most. It’s such an open field, and if you come up with something that has a clinical or diagnostic application, that’s a home run.