Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UI engineers conduct residential soils study, one of few such U.S. studies ever done

30.11.2011
University of Iowa engineers have published their findings from a study of residential soils in the city of Cedar Rapids, making it one of only a few such U.S. urban soil studies ever conducted.

The authors of the study, published in the November online edition of the journal Environmental Pollution, collected soils in the residential areas of downtown Cedar Rapids and analyzed them for industrial pollutants known as PCBs (polychlorinated biphyenyls) and chlordanes. Measured values for both chemical groups were found to be similar to other urban/industrial sites around the world. Also, measured values were found to be of the same order of magnitude as the provisional threshold recommended by the U.S. EPA to perform soil remediation.

Project principal investigator Keri Hornbuckle, UI professor of civil and environmental engineering and researcher at IIHR-Hydroscience and Engineering, says that soil often stores residual amounts of persistent organic pollutants such as PCBs and chlordanes and -- because children and others can be be exposed on a regular basis -- contaminated soil may be a source of concern.

Hornbuckle notes that her study is somewhat unique because the few existing reports of chlordanes or PCBs in U.S. soil samples concern remote, unpopulated areas. In researching similar studies, she found only one study reporting chlordanes and two reporting PCBs for U.S. urban-residential soil concentrations. She adds that her study was aided by the fact that she grew up in Cedar Rapids and that several former Cedar Rapids teachers -- who were very familiar with the city -- assisted the team while sampling was being conducted.

During the historic floods of 2008, flooding of the Cedar River exceeded the historical record of flood discharge in Cedar Rapids and affected a large portion of residential, commercial, and industrial land in the city, including Cedar Lake. Having an average depth of less than four feet, Cedar Lake was long used as a cooling lake for the Sixth Street Generating Station and is contaminated with chlordanes and PCBs. It remains unknown whether the 2008 flooding caused any redistribution of those pollutants in the city, says Hornbuckle.

The UI study technique involved collecting 66 soil samples near Cedar Rapids streets on August 25, 2008 -- about 70 days after the flood. About 94 percent of the sampling sites were located inside the estimated flood area, and researchers concentrated on sampling sites south of Cedar Lake and west of the Cedar River. The total sampling area covered almost 4 square miles. Each sample involved collecting approximately 2 pounds of soil from a 5-inch-deep site using a trowel. The soil samples were placed in labeled, plastic Ziplock freezer bags and brought to the UI, where they were refrigerated prior to being analyzed -- using gas chromatography, mass spectrometry for chlordanes, and tandem mass spectrometry for PCBs.

Hornbuckle says that residents of Cedar Rapids and other cities should know that these chemicals are widely present in urban soils. She adds that we don't know the source of the PCBs found in Cedar Rapids soils, but that chlordane is probably present because homeowners used the insecticide to kill termites and that the original contamination probably occurred more than 30 years ago.

"Both these chemicals are now banned from production and sale, but are still in our environment because they are nearly nonbiodegradable," she says. "It is my opinion that we should not use chemicals that are so persistent in any household activity, but it is difficult for the average homeowner to know how to judge this. This data is not, but should be, provided on the containers of all the products we purchase."

Manufactured from about 1930 until being banned in the 1970s due to their toxicity and persistence in the environment, PCBs were widely used as coolants, in electrical transformers and in a wide variety of products ranging from waterproofing compounds to paints and pesticides. Chlordanes were used to control termites in buildings and as insecticides on lawns and gardens, as well as on corn and other crops, before the EPA banned their use in 1988.

The project was funded by the National Science Foundation (NSF) and as part of the Iowa Superfund Basic Research Program, which is funded by the National Institutes of Health.

The paper, titled "Spatial distribution of Chlordanes and PCB congeners in soil in Cedar Rapids, Iowa, USA," is scheduled for publication in the February 2012 print edition of the journal.

Hornbuckle's co-authors are Andres Martinez, Nicholas R. Erdman, Zachary L. Rodenburg, and Paul M. Eastling, all of the UI Department of Civil and Environmental Engineering and IIHR -- Hydroscience and Engineering. Of special note, Erdman and Rodenburg performed all chemical analysis required for the study while enrolled as UI undergraduate chemical and biochemical engineering students, and Eastling reported a draft of the study in his master's degree thesis in environmental engineering.

STORY SOURCE: University of Iowa News Services, 300 Plaza Centre One, Suite 371, Iowa City, Iowa 52242-2500

MEDIA CONTACTS: Keri Hornbuckle, principal investigator, 319-331-3053, keri-hornbuckle@uiowa.edu; Gary Galluzzo, writer, 319-384-0009, gary-galluzzo@uiowa.edu

Jennifer Brown | EurekAlert!
Further information:
http://www.uiowa.edu

More articles from Studies and Analyses:

nachricht Some brain tumors may respond to immunotherapy, new study suggests
11.12.2018 | Columbia University Irving Medical Center

nachricht Climate change and air pollution damaging health and causing millions of premature deaths
30.11.2018 | International Institute for Applied Systems Analysis (IIASA)

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Data use draining your battery? Tiny device to speed up memory while also saving power

14.12.2018 | Power and Electrical Engineering

Tangled magnetic fields power cosmic particle accelerators

14.12.2018 | Physics and Astronomy

In search of missing worlds, Hubble finds a fast evaporating exoplanet

14.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>