CGRER researchers improve predictability of extreme winter haze events

Fine particulate pollution creates a winter haze over Hong Kong during December of 2009. (Jason Thien/flickr)
Jenna Ladd | December 27, 2016

Meng Gao and Gregory R. Carmichael have published research in Science Advances, an open-access peer-reviewed multidisciplinary scientific journal, that further explains extreme winter haze events in China.

Carmichael is a Karl Kammermeyer Professor of Chemical and Biochemical Engineering and co-director of the University of Iowa Center for Global and Regional Environmental Research (CGRER). Gao is a former University of Iowa postdoctoral research scholar that is currently a postdoctoral fellow at the John A. Paulson School of Engineering and Applied Sciences of Harvard University.

While working with Carmichael at the University of Iowa, Gao researched how well extreme winter haze pollution events in China could be predicted using state-of-the-art scientific models.

Sulfates are formed by reactions in the atmosphere or on aerosol surfaces. Prior to their recently published research, predicting rapid and heavily concentrated sulfate particulate formation was difficult. The report explains that previous models relied on photochemical oxidants, but because there is limited photochemistry activity during heavy haze events, they are not able to predict those events with the highest sulfate concentrations very well. Carmichael and Gao were only able to predict the correct number of sulfate particulates if they created an additional reaction pathway to create sulfate on particles.

The researchers note that winter haze poses health risks for more than 400 million people in the North China Plain. Sulfate is a major element in fine haze particles. This research follows record sulfate concentrations which led to the extreme winter haze event of 2013 in Beijing.

Carmichael explained, “By incorporating this new reaction pathway into our air quality model, our ability to predict winter time haze events has improved dramatically. Furthermore this more detailed understanding of how fine particles are formed will help guide more effective control measures.”

Amish home environment linked to asthma prevention

Amish children are frequently exposed to microbes from farm animals that have been shown to strengthen their innate immune systems. (bluebird87/flickr)
Jenna Ladd | August 9, 2016

A recent study published in the New England Journal of Medicine suggests that a less dusty house is not always a healthier house. 

A multidisciplinary team of researchers from several universities, including CGRER member and professor and head of the University of Iowa Department of Occupational and Environmental Health, Dr. Peter Thorne, found that particular characteristics of the Amish household bolster children’s immune systems and prevent asthma.

Researchers began with comparing two seemingly similar communities, the Amish of Indiana and the Hutterites in South Dakota. Even though the two groups share comparable genetic backgrounds, diets, and lifestyles, a compelling difference in the number of asthmatic children was found. About 21% of Hutterite children aged 6-14 have asthma while only 5% of Amish children, about half the national average, have been diagnosed. Scientists posit that one major difference between the communities accounts for this trend: farming practices.

Hutterite communities operate large, industrialized farms that utilize electricity. Dairy barns are often located a distance away from family homes and children do not play in them. In contrast, the Amish keep single-family, electricity-free dairy farms. Horses are used to power the farms and for transportation. Dairy barns are often located near the family home and are an acceptable play area for children.

The scientists began with a modest study, comparing immune cells found in blood samples from 30 Amish and 30 Hutterite children, all aged 7-14. All 30 of the Amish children were found to have high counts of neutrophils, or white blood cells that act as the body’s “innate immune system.” None of the Amish were found to have asthma. In contrast, 6 of the Hutterite children had an asthma diagnosis and all of them had considerably lower levels of neutrophils in the blood.

Researchers also placed Electrostatic Dust Samplers inside the homes the Amish and Hutterite children to measure toxins and airborne particulates. The electricity-free samplers found that Amish house dust was “much richer in microbial products” from farm animals that are carried into the home. The microbial life found inside the Amish children’s homes explains their spiked neutrophil levels that prevent asthma.

The team was able to corroborate the results in animals, Thorne explains, “When we administered extracts of the two types of dust to mice, we were able to reproduce the differences in respiratory allergy that we observed in the Amish and Hutterite children.”

Dr. Talal Chatila a Harvard Medical School immunologist who wrote an editorial published along with the report said, “it is not far-fetched to start thinking of how one could harness those bacteria for a therapeutic intervention.”

The team also included researchers from the University of Chicago, the University of Arizona, Dr. von Hauner Children Hospital in Munich, Germany, and Allergy and Asthma Consultants, Indianapolis.

CGRER Research Focus – Kajsa Dalrymple

Kajsa Dalrymple, an assistant professor in the University of Iowa’s School of Journalism and Mass Communication, explains her research on communicating with the public about water sustainability issues. Dalrymple is one of ten new faculty members hired at the University of Iowa as part of their Water Sustainability Initiative.

CGRER Research Focus – Hans-Joachim Lehmler

Hans-Joachim Lehmler, an associate professor in the University of Iowa’s Department of Occupational & Environmental Health, explains his research on how different organisms process the toxic compounds PCBs. Lehmler is one of ten new faculty members hired at the University of Iowa as part of their Water Sustainability Initiative.

CGER Research Focus – Craig Just

Craig Just, an assistant professor in the University of Iowa’s Department of Civil and Environmental Engineering, explains his research on how mussels process nitrogen. This research will help Just quantify the impact mussels have on filtering nitrogen that enters the Mississippi River from Iowa, which ultimately causes a dead zone in the Gulf of Mexico. Just is one of ten new faculty members hired at the University of Iowa as part of their Water Sustainability Initiative.

CGRER Research Focus – Adam Ward

Adam Ward, an assistant professor in the University of Iowa’s Department of Geoscience, explains his research on the transport of water and what it carries through the landscape. Ward is one of ten new faculty members hired at the University of Iowa as part of their Water Sustainability Initiative.

CGRER’s research video projects

CGRER's YouTube page
CGRER’s YouTube page

Iowa Now has featured an article about the research video projects that the Center for Global and Regional Environmental Research (CGRER) is producing.

The first series of videos created by CGRER primarily focuses on graduate student researchers at UI. Those videos are available on the CGRER Research Focus YouTube channel.

The next series of videos features faculty members involved in UI’s water sustainability initiative. Those videos will be released on this blog when they’re finished.

Check out the Iowa Now article here.

CGRER Research Focus – Seyed Hajimirzaie

Seyed Hajimirzaie, a PhD student in the University of Iowa’s Civil and Environmental Engineering Department, discusses how knowledge of water flow patterns around mussels not only helps mussel populations, but can also be applied to a variety of other situations involving both water and air flow.

For more CGRER Research Focus videos, check out our Youtube Channel.

CGRER Research Focus – Pablo Saide

Pablo Saide, a research assistant in the University of Iowa’s Environmental Engineering department, discusses his completed research modeling air quality in Santiago, Chile.

For more CGRER Research Focus videos, check out our Youtube Channel.