Bulletin E-Edition:
Air pollution an unwanted import
Sensors at Mount Bachelor track pollution blown into Central Oregon from China
By Kate Ramsayer / The Bulletin
Published: August 20. 2006 4:00AM PST
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The air skimming across the top of Mount Bachelor is some of the cleanest in the Northwest.
To a handful of scientists, that makes it the perfect place to study pollution.
"It's sort of ironic that we have to go to one of the cleanest locations to look for pollutants," said Daniel Jaffe, a professor of atmospheric and environmental chemistry at the University of Washington, Bothell.
Since 2004, Jaffe and scientists at Oregon State University and Central Oregon Community College have been measuring and collecting air samples from the 9,065-foot peak.
They're looking for contaminants that have traveled across the ocean from China and other Asian countries. Although the pollutants show up at all elevations, they're easier to track on mountaintops, above the layer of smog and emissions that come from local activities and industries.
Most days, the level of pollution detected on Mount Bachelor is quite low, Jaffe said, and is noticeable only because the scientists have very sensitive instruments.
But on an average of one day a year, depending on the winds, the levels of pollution from overseas increase.
"You can't blame other countries for most of your pollution," Jaffe said. "That said, this long-range transport of pollution shows that we live on one planet."
The pollution arriving from overseas isn't at levels that are hazardous here for people's health. But as China's industries grow, the Northwest could see higher levels of pollution coming across the Pacific, Jaffe said. To track any changes that do occur, scientists need to do long-term monitoring projects, and Mount Bachelor is probably the best site for such work on the West Coast, he said.
A site for studies
Nine years ago, Jaffe's research group first detected Chinese pollution at measuring stations on the Washington coast. The discovery was met with skepticism, Jaffe said, but since then, particles from China have been picked up by other scientists, as well.
Because these pollutants are usually carried across the globe between 6,000 and 20,000 feet in the atmosphere, a few years ago Jaffe went hunting for a high-elevation site where he could monitor the air for contaminants from far away, he said.
Not just any Northwest peak would do. Jaffe was looking for a place with electricity to operate scientific equipment. He also wanted a site where researchers could access the instruments, but where there weren't too many roads with cars spitting out emissions. And he wanted a place where there weren't many oil-fired heaters or other pollution-generating machines.
A research site on a volcano is also preferable, he said, since those peaks are usually isolated, without other mountains in the way to disrupt the air flow coming in from the Pacific.
These features came together at Mount Bachelor, where the ski area and its chairlifts provided access for most of the year and the staff was cooperative in accommodating the scientists, Jaffe said.
The mountain is also the site for research conducted by Staci Simonich's lab at Oregon State University, which is looking at the long-distance travels of pesticides and pollutants.
"It's high enough that it points up into the air that's moving quickly around the globe, so it's more influenced by the long-range (pollution) sources than the local sources," said Kimberly Hageman, a postdoctoral researcher in Simonich's lab.
The two research groups are using different methods to look at different chemicals carried around by air currents.
Jaffe's group is focusing on metals such as mercury as well as gases, including carbon monoxide, ozone and nitrogen oxides.
At the summit, tubes pump air from outside the building to 10 measuring devices inside. Most of the devices work by shining different wavelengths of light through the air sample and identifying its composition based on which wavelengths are absorbed. The results are automatically sent back to Jaffe's lab and his Web site.
To trace the pollution back to its source, Jaffe looks at a number of clues. Sometimes, if there is a big event like a fire or a dust storm across the globe, he can see the pollution mass crossing the ocean from Asia on satellite data.
Most of the pollution events are smaller, however. In those cases, computer programs can trace the path of the winds in the Northwest to see where they originated. In addition, other scientists have identified patterns of trace metals that are unique to Chinese pollution, kind of like a pollution fingerprint, Jaffe said.
In his work on Mount Bachelor, Jaffe is looking for a mercury fingerprint of Chinese pollution, which could be used to identify and trace the contaminants. China is the largest consumer of coal in the world, he said, and the coal from that region is especially rich in mercury.
"A lot of mercury is released from their combustion," he said. "That's an environmental issue, and that's also a way we can trace their pollution."
Some of the mercury that accumulates in fish is from global sources, Jaffe said, and some is from more local sources. Sorting out how much comes from where is a complicated process that his experiments could shed some light on.
According to the federal Environmental Protection Agency, consuming high levels of mercury can harm nervous system development of a fetus or young child. The agency sets recommendations for how much high-mercury fish young children and women who are pregnant, might become pregnant or are nursing should eat.
While the foreign contaminants arriving here do not exceed any health standard by themselves, in combination with local sources they could pose a problem, Jaffe said.
For example, at their highest, the incoming pollution could comprise between 30 percent and 40 percent of the pollution limit that local air quality managers set. If local industries usually emit pollution that is 80 percent of the limit, that would be fine most days. But the added pollution from overseas would push the region's air into the unhealthy category.
"Because it raises the background level (of pollution), we have to reduce our own more to get clean air," Jaffe said.
And as China grows, there is a need to track what is coming from overseas with good, long-term measurements, he said.
"I think we need to be operating that site as a longer-term facility," he said. "We ought to have a way of understanding if this is getting worse or better."
Mount Bachelor is already popping up on the radar of others in the research community, he said. In the spring, a NASA research plane flew within a couple hundred feet of the summit to collect air samples, which gives the researchers more data to compare.
Well-traveled pesticides
While Jaffe is studying metals and some gases, Oregon State's Simonich and her students are using equipment at the building at the top of the ski area's Summit Chairlift to study semivolatile compounds, which are gaseous at warmer temperatures, but condense into a liquid when they hit cooler climes.
"It leads them to have a unique behavior in the environment," Hageman said.
Most synthetic pesticides are semivolatile compounds, she said. When people spray them in a warm agricultural valley, they can evaporate and be carried around by air currents.
"Then the wind can push them around to any place on the globe, even far distances from where they were used," she said.
But when the compounds get to a cold place, they can condense into a liquid form, much like water condenses on cold glass on a hot day.
"That leads them to accumulate in cold environments on the Earth, such as mountains," Hageman said.
Using instruments in the ski area's summit building, the Oregon State researchers collect air samples and look for traces of 150 different organic compounds.
"We're just trying to understand this global pollution, what goes on across the ocean, and how that affects us in the Pacific Northwest," said Toby Primbs, a graduate student in Simonich's lab who works with the Mount Bachelor data.
They collect the data using a machine that is a lot like a vacuum cleaner, he said, except with pricier filters and a big pump. Over a 24-hour period, air is pulled in through a filter that traps particles and some polyurethane foam that catches gaseous compounds.
Back in the lab, Primbs extracts the compounds from the filters and the foam, then analyzes them to find out what is there and in what amounts.
He is looking for pesticides - both those currently used and those that have been banned but are still floating around in the atmosphere - as well as combustion-caused pollutants called polycyclic aromatic hydrocarbons.
The idea is to make connections between the days when there are high concentrations of pollutants and the places where the wind was blowing from, Hageman said.
Scientists can pick a day and a site and plug that information into a computer model to find the wind origins for the last 10 days, she said.
For example, perhaps on Aug. 1 the air that reached Mount Bachelor was from China, but on Aug. 3 it came from Alaska and on Aug. 6 it came from California.
The investigators are still collecting and analyzing data from Mount Bachelor. But a previous study from a peak on Washington's Olympic Peninsula showed higher concentrations of contaminants on some days when air had come from China.
Some data the scientists have collected on Mount Bachelor shows the presence of bigger amounts of combustion-caused pollutants, Primbs said, which matches some of the profiles of what is coming out of China.
Still, another experiment done by the Oregon State researchers in western national parks demonstrated that although there are contaminants reaching the West Coast from China, the stronger pollution influence comes from nearby sources, Hageman said.
The scientists are trying to figure out what pollutants are making their way across the ocean and where they come from, laying the groundwork for further studies that will look into how much of a problem the pollutants are, she said.
The pesticides and other pollutants found on Mount Bachelor aren't at a level that people need to be concerned for their health, she said, adding that it wouldn't be a problem to melt the snow and drink it while backpacking.
"We're not finding anything that's an immediate danger," she said.
Instead, Hageman said the research sends the message that actions in one place have effects elsewhere.
"Our contaminants do end up in remote and pristine places," Hageman said. "If you use them in your garden it's not like they're going to stay in your garden or in the farms."
The research that is happening on top of Mount Bachelor demonstrates the connections between science and policy, said Carol Higginbotham, a chemistry instructor at Central Oregon Community College.
Higginbotham and her students have helped the other research groups by collecting samples, keeping records and doing maintenance on the equipment.
"It's been a really great ride, I'm having a lot of fun with the whole thing," she said.
The projects are also a good chance for her students to see how science involves collaborations between researchers that leads to new, and perhaps unpredictable, results.
"Students have been able to connect with that, and I think that's an exciting thing for them," Higginbotham said.
The work also shows students that policies in one country can affect other countries, she said. "Pollution," she said, "sees no borders."
Kate Ramsayer can be reached at 617-7811 or at kramsayer@bendbulletin.com.
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