Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Post-Katrina: Lead in disturbed soil may pose heightened health risk

15.12.2005


Unsafe levels of lead have been found in soil and sediments left behind in New Orleans following Hurricane Katrina and could pose a heightened health threat to returning residents, particularly children, according to a new study published in the American Chemical Society’s journal Environmental Science & Technology. In some soil samples collected from the area, lead levels were as much as two-thirds higher than what the U.S. Environmental Protection Agency considers safe, according to researchers at Texas Tech University.



High concentrations of lead in the city’s soil have previously been reported by others, but lead generally remains embedded in the soil and does not easily come in contact with people unless disturbed, says study leader Steven M. Presley, Ph.D., an environmental toxicologist at Texas Tech in Lubbock. He says that severe flooding may have loosened large amounts of embedded lead and caused it to be deposited on soil surfaces, where exposure to lead particles is more likely, either through skin contact or the inhalation of aerosolized particles. Lead exposure is a particular health concern among children because it can impair the nervous system and cause developmental problems.

Although lead is the biggest health concern, the scientists also found concentrations of aldrin (an insecticide), arsenic, and seven semivolatile organic compounds that exceeded EPA Region VI safe levels and are on EPA’s list of known or suspected human carcinogens. In all, the researchers analyzed the sediment and soil samples for 26 metals and more than 90 semi-volatile compounds.


In addition to sediment and soil samples, the researchers also tested water and animal tissues following the flood. Other contaminants found among samples include high levels of iron, several banned pesticides and pathogenic bacteria, but the researchers say that concentrations of most of these contaminants were unlikely to pose an immediate human health threat. The peer-reviewed study, which represents one of the most detailed environmental sampling efforts to date following the flooding caused by Katrina, will appear in the Jan. 15 issue of ES&T.

"The purpose of this study is to gather more extensive samples and establish baseline data upon which to evaluate the long-term environmental impact of the storm," says Presley. "It may take years before we really know the full extent of the human health risks and wildlife impact from the Katrina contaminants, but this is an important step."

The researcher cautions that this study alone won’t answer the much debated question of whether it is safe to return to the area. Nonetheless, says Presley, people should be made aware of the contaminants that are present and take appropriate cleanup measures to minimize the potential health risks. For the current study, the research team obtained sediment, soil, water and animal tissue samples over a three-day period (Sept. 16-18) from across a broad cross-section of the city 18 days after the hurricane struck and after most of the water had been pumped from the city. The sampling included 14 different sites in the New Orleans area and focused mainly on the sediment and soil.

Floodwater samples taken at some sites showed extremely high levels of bacteria, particularly Aeromonas hydrophila, a little known human pathogen that can cause diarrhea and wound infections. This is the first time that Aeromonas has been detected in the Katrina floodwaters, Presley says. Animal tissues sampled, including dead snakes and an alligator, also contained multiple metals and pesticides, but these levels were generally within an expected range and not likely to be caused by the hurricane, the researchers say. Of the 47 mosquito specimens collected in the study area, all tested negative for West Nile Virus and St. Louis Encephalitis, says Presley. But he cautions that virus-transmitting mosquito populations might increase in the spring and summer.

The researchers are planning to expand their sampling study to include additional cross-sections of the city, Presley says. The Institute of Environmental and Human Health at Texas Tech University and the Patent & Trademark Institute of America provided funding for this study.

Charmayne Marsh | EurekAlert!
Further information:
http://www.acs.org

More articles from Ecology, The Environment and Conservation:

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>