Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Combination of Gulf oil and dispersant spell potential trouble for gut microbes

23.10.2012
A study to be published in mBio®, the online open-access journal of the American Society for Microbiology, on Tuesday, October 23, examined whether crude oil from the 2010 Deepwater Horizon oil spill, the dispersant used on it, or a combination of the two might affect the microbes of the human digestive tract.

The researchers found that although high concentrations of oil combined with dispersant are detrimental to these helpful microbial communities, the low to undetectable concentrations typically found in Gulf shellfish had no discernable effect.

"The oil and the dispersant were not hazardous or toxic to the bacteria [at the tested concentrations], but when you combined them and increased the concentrations, you got a dose-response effect," says Carl Cerniglia of the National Center for Toxicological Research at the U.S. Food and Drug Administration (NCTR, FDA), a senior author on the study.

The Deepwater Horizon oil spill released roughly 4.9 million barrels of crude oil into the northern Gulf of Mexico in the spring and summer of 2010. To accelerate dispersion and enhance breakdown of the oil by microorganisms, 1.5 million gallons of the dispersant COREXIT 9500 were sprayed on the surface of the spill and applied at the underwater source of the leak. Concerns were soon raised about the safety of that dispersant for wildlife, plants, and humans alike. Oysters, shrimp, and other delicacies could well bioaccumulate oil or dispersant in their tissues, so eating contaminated shellfish presents one possible route by which humans could be exposed.

Although studies of the toxicity of crude oil and COREXIT 9500 to the human body have been carried out, science has not explored whether the dispersant or a mixture of oil and dispersant could have an impact on the microorganisms that line our intestinal tracts and aid in digestion, enhance immunity, and manufacture essential vitamins that the body absorbs.

Cerniglia and his colleagues combined human fecal samples, which are loaded with the microorganisms that reside in the intestines, with varying quantities of Deepwater Horizon crude oil and the dispersant, and then tested the samples to see how the microorganisms fared.

The crude oil and dispersant together had a greater toxic effect on the microbes present in the fecal samples, says Cerniglia, apparently because the dispersant is doing what it was designed to do: break up the oil blobs into smaller blobs with greater surface-to-volume ratios and greater bioavailability. "By adding the dispersant to the crude you're solubilizing the oil, which may make it more bioavailable to the organisms and create a potentially toxic response."

The oil and dispersant affected some types of bacteria more than others, says Cerniglia. In fecal samples from all three volunteers in the study that were treated with oil and dispersant, the abundance of Escherichia coli increased while the abundance of Bacteroides uniformis and uncultured Faecalibacterium were reduced. This is important because high densities of E. coli have been associated with greater susceptibility to foodborne infections.

Cerniglia cautions that although the findings reveal that dispersant and crude oil together can have a negative impact on the human microbiome, it is important to note that the concentrations of these materials in seafood are typically well below the concentrations used in this study.

"We had to get to the higher concentrations to see an effect," says Cerniglia. "And that's not a typical concentration that would be found in a residue analysis of seafood." Hence, although high concentrations of oil and dispersant can impact gut communities, there is no evidence to indicate shellfish harbor great enough quantities of these materials to have an effect. "It's almost like a worst case scenario, but that's the kind of information one needs to know in the beginning," so that scientists can eventually discern what safe levels of exposure to oil-dispersants mixtures might be.

Moving forward, Cerniglia says his group would like to expand the preliminary study to include samples from a greater number and variety of volunteers. "The microbiota of each individual is unique. We provided information with the three individuals' fecal samples that we used, but we'd like to expand that," Cerniglia says.

mBio® is an open access online journal published by the American Society for Microbiology to make microbiology research broadly accessible. The focus of the journal is on rapid publication of cutting-edge research spanning the entire spectrum of microbiology and related fields. It can be found online at http://mBio.asm.org.

The American Society for Microbiology is the largest single life science society, composed of over 39,000 scientists and health professionals. ASM's mission is to advance the microbiological sciences as a vehicle for understanding life processes and to apply and communicate this knowledge for the improvement of health and environmental and economic well-being worldwide.

Jim Sliwa | EurekAlert!
Further information:
http://www.asmusa.org
http://mBio.asm.org

More articles from Studies and Analyses:

nachricht When a fish becomes fluid
17.12.2018 | Institute of Science and Technology Austria

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

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 storage using individual molecules

Researchers from the University of Basel have reported a new method that allows the physical state of just a few atoms or molecules within a network to be controlled. It is based on the spontaneous self-organization of molecules into extensive networks with pores about one nanometer in size. In the journal ‘small’, the physicists reported on their investigations, which could be of particular importance for the development of new storage devices.

Around the world, researchers are attempting to shrink data storage devices to achieve as large a storage capacity in as small a space as possible. In almost...

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...

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

When a fish becomes fluid

17.12.2018 | Studies and Analyses

Progress in Super-Resolution Microscopy

17.12.2018 | Life Sciences

How electric heating could save CO2 emissions

17.12.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>