Research/Academic Showcase

Researchers at Texas Tech University Find Toxic and Pathogenic Contaminants in New Orleans Soils and Water

Following massive flooding in New Orleans after Hurricane Katrina, CNN reporter Miles O’Brien broadcasted live from a sludge-covered area and said, “I want to know what is in this muck.”

His comment piqued the curiosity of scientists at The Institute of Environmental and Human Health, who traveled in September to the Big Easy to collect soil, sediment and standing water samples.

Their results, which found unsafe levels of toxic metals, biological and chemical contaminants, were published Dec. 14 in the on-line version of The American Chemical Society’s peer-reviewed journal, Environmental Science and Technology.

Steven Presley, research coordinator for the Admiral Elmo R. Zumwalt, Jr. National Program for Countermeasures to Biological and Chemical Threats at the TTU institute, serves as the principal investigator for the research project.

He and his multidisciplinary team of 12 scientists found unsafe levels of 11 toxicants in sediment, soil and water samples. They uncovered arsenic, lead, pesticides and Aeromonas – a pathogenic bacterium.

“We recognized the real potential for dispersion of huge amounts of hazardous materials in the floodwaters,” Presley says. “We wanted to get baseline information on what kinds of contaminants or toxicants were present in the soil, the water and the whole area as a result of the flooding.”

Researchers took numerous soil and sediment samples from a six-mile stretch of road through the middle of the city and from two sites in the wetlands around New Orleans.

Lab analyses found two samples containing lead that exceeded the U.S. Environmental Protection Agency’s Human Health Soil Screening Levels, which are used to determine a human health threat. Also, the samples exceeded EPA High Priority Bright Line Levels, which the agency uses to prioritize and plan for hazardous materials cleanup.

As well as chemicals, researchers uncovered areas in the city where water samples showed high levels of Aeromonas bacteria.

Aeromonas levels were higher than anything we’ve seen in playa lakes around Lubbock, or what's been published in the scientific literature,” says John Zak, chairman of the Department of Biological Sciences. “The levels from New Orleans are some of the highest levels reported to date from polluted areas. What is unique about Aeromonas is it is an opportunistic pathogen that can get into open wounds. It may be difficult to treat, because Aeromonas can be resistant to antibiotics.”

While Presley believes more science is needed to understand the entire scope of contamination in New Orleans, workers and homeowners potentially run the risk of inhaling toxic pollution and microbial agents that reside in the dried sediment stirred up by the rebuilding process.

Children could be most at risk for ingesting lead contained in sediment as they play in the dirt and put their hands in their mouths. Ingestion of lead by children can cause developmental problems and impaired nervous systems.

The team plans to travel back to New Orleans for a third study in January.

For more information on the research, visit www.neworleanspollution.texastech.edu.

- John Davis

 

Jan 15, 2020