Magnetic leaves reveal Bellingham's most polluted byways
October 15, 2009
Tree leaves along bus routes in Bellingham, WA, were found to be up to 10 times more magnetic than leaves on quieter streets. Magnetism comes from tiny particles of pollution -- such as iron oxides from diesel exhaust -- that float through the air and either stick to leaves or grow right into them. This photo of a larger particle, taken with a scanning electron microscope, shows one of the Fe-oxide spheres produced by combustion, and collected with a double-sided tape collector. Credit: Rachel Housen, Whatcom Middle School/Bellingham High School.
Tree leaves may be powerful tools for monitoring air quality and planning biking routes and walking paths, suggests a new study by scientists at Western Washington University in Bellingham. The research will be presented at this month's Annual Meeting of the Geological Society of America in Portland, Oregon.
Leaves along bus routes were up to 10 times more magnetic than leaves on quieter streets, the study found. That magnetism comes from tiny particles of pollution -- such as iron oxides from diesel exhaust -- that float through the air and either stick to leaves or grow right into them.
Geophysicist Bernie Housen and colleague Luigi Jovane collected several leaves from 15 trees in and around Bellingham. Five of the trees lay next to busy bus routes. Five sat on parallel but much quieter side streets. Five were in a rural area nearby.
Using two measurement techniques, Housen and Jovane found that leaves along bus routes were between two and 8 times more magnetic than leaves from nearby streets and between four and 10 times more magnetic than rural leaves.
Inhaling particulate matter has been linked to a number of negative health consequences, including breathing troubles and even heart problems. Tiny particles bypass the airways and get deep into the lung tissues.
This photo, taken with a scanning electron microscope, shows several small magnetic particles from pollution -- such as iron oxides from diesel exhaust -- on a (wavy) leaf. Credit: Sadie Belica, Western Washington University Geology Department
The new study suggests that biking or walking along heavy bus routes might be as bad for your health as you might suspect when choking on exhaust fumes. That's something cities might want to consider as they plan new routes for cyclists and pedestrians."I ride my bike to work every day," Housen said. "I've always wondered what the effects of diesel exhaust are on my health."
While many details remain to be worked out, the study also suggests that collecting tree leaves can be a simple and effective way to measure the load of particulate matter in the air. European researchers have been exploring the idea for a while, but this is one of the first studies to apply the technique in the United States.
"Using trees is a nice, low-tech way to do these studies and you don't need to use fancy particle collectors," Housen said. "If it works, you could easily collect a lot of data from a region. You could even have kids collect leaves. That makes it a powerful tool to see variation of particulate matter on a very detailed level."
More information: View research abstract at http://gsa.confex. … t_164610.htm
Source: Geological Society of America
-
Research finds diesel exhaust kills throat cells
Sep 11, 2007 |
not rated yet |
0
-
Why do autumn leaves bother to turn red?
Oct 25, 2007 |
not rated yet |
0
-
Tree-destroying wasp spreads in Hawaii
Oct 10, 2006 |
not rated yet |
0
-
Diesel exhaust fumes affect people with asthma, study finds
Dec 06, 2007 |
not rated yet |
0
-
Winning by a neck -- Giraffes avoid competing with shorter browsers
Dec 22, 2006 |
not rated yet |
0
-
Engineers build first sub-10-nm carbon nanotube transistor
Feb 01, 2012 |
4.9 / 5 (30) |
30
-
Something old, something new: Evolution and the structural divergence of duplicate genes
Jan 31, 2012 |
4.6 / 5 (7) |
1
-
The hidden nanoworld of ice crystals: Revealing the dynamic behavior of quasi-liquid layers
Jan 30, 2012 |
5 / 5 (3) |
1
-
Stock market network reveals investor clustering
Jan 27, 2012 |
3.9 / 5 (23) |
8
-
Of microchemistry and molecules: Electronic microfluidic device synthesizes biocompatible probes
Jan 26, 2012 |
5 / 5 (1) |
0
-
Discrepancy between oxygen and carbon-dioxide levels
13 hours ago
-
where gems are found in the world
17 hours ago
-
Wind Waves in Reservoir ~ Wind run-up and Wind set-up
Feb 08, 2012
-
Balance of oxygen in the atmosphere
Feb 01, 2012
-
The case for a methanol-based economy
Jan 30, 2012
-
Weather in a rotating cylinder
Jan 25, 2012
- More from Physics Forums - Earth
More news stories
Humans may have helped the decline of African rainforests 3000 years ago
(PhysOrg.com) -- Large areas of rainforests in Central Africa mysteriously disappeared over three thousand years ago, to be replaced by savannas. The prevailing theory has been that the cause was a change ...
Could Venus be shifting gear?
(PhysOrg.com) -- ESAs Venus Express spacecraft has discovered that our cloud-covered neighbour spins a little slower than previously measured. Peering through the dense atmosphere in the infrared, the ...
Space & Earth / Space Exploration
2 hours ago |
5 / 5 (3) |
4
|
Clam fields found at deep, low-temperature Mariana vents
(PhysOrg.com) -- Scientists have marveled at the unusual life forms thriving at high temperature hydrothermal vents of the deep ocean.
Space & Earth / Earth Sciences
2 hours ago |
not rated yet |
0
|
Mars Science Laboratory computer issue resolved
(PhysOrg.com) -- Engineers have found the root cause of a computer reset that occurred two months ago on NASA's Mars Science Laboratory and have determined how to correct it.
Space & Earth / Space Exploration
3 hours ago |
5 / 5 (4) |
2
|
Two new moons for Jupiter
Advances in technology have lead to the discovery of new planets outside of our Solar System, and now even new moons in our own backyard.
Space & Earth / Space Exploration
2 hours ago |
not rated yet |
2
Curry spice component may help slow prostate tumor growth
Curcumin, an active component of the Indian curry spice turmeric, may help slow down tumor growth in castration-resistant prostate cancer patients on androgen deprivation therapy (ADT), a study from researchers ...
Netflix light on flicks as viewers soak up TV shows
Like most fresh faces that arrive in Hollywood, Netflix wanted to be a movie star. But now it's learning what many in Tinseltown have known for decades: Movies are sexy, but the real money is in television.
Antidepressants and pregnancy: Women must consider the impact of drugs on baby, and of depression on baby, themselves
Upon learning they are pregnant, most women dutifully nix the alcohol, sushi and caffeine. But what about antidepressants?
Arthritic knees, but not hips, have robust repair response
Researchers at Duke University Medical Center used new tools they developed to analyze knees and hips and discovered that osteoarthritic knee joints are in a constant state of repair, while hip joints are not.
The power of estrogen -- male snakes attract other males
A new study has shown that boosting the estrogen levels of male garter snakes causes them to secrete the same pheromones that females use to attract suitors, and turned the males into just about the sexiest ...
Fool's gold may prove an unlikely alternative to overexploited catalytic materials
Catalytic materials, which lower the energy barriers for chemical reactions, are used in everything from the commercial production of chemicals to catalytic converters in car engines. However, with current catalytic materials ...

Oct 16, 2009
Rank: 1 / 5 (1)