MUSC News Center
MUSC researchers pinpoint how oil spill disasters affect human health
By Dawn Brazell | News Center | Nov. 24, 2014
|Dr. Louis Guillette (right) works with Ph.D. student James Nifong, using National Geographic's Crittercams to capture video footage from alligators to get a view into their private lives. The study results were published in the January 2014 issue (volume 9) of PLOS One.|
It may be decades before researchers will truly know how the Deepwater Horizon (DWH) oil spill will affect human health.
Four researchers at MUSC from four varying specialties hope to speed up that timetable and use the spill to reveal other secrets in how the environment and genetics interact to cause disease.
The researchers all have unique views into the problem.
The group’s major focus is to determine if exposure to crude oil – specifically the mixture represented by the Deepwater Horizon (DWH) oil spill – affects long-term human health. The other critical question, just as in research being done by Michael Fulton, Ph.D, in his mesocosm studies, is whether the dispersant used on the spill to break down the oil also has detrimental health effects.
In other words, is the ‘cure’ causing more harm?
Spyropoulos said diluted mixtures of substances might be just as potent as more concentrated single components of those mixtures, suggesting that single-component testing may be misleading as far as determining safe levels of exposures.
“Dispersant was deemed non-toxic at low “working” dilutions. It’s been sold as something that allows for easier breakdown of crude oil by microorganisms, but it also makes oil components more bioavailable to people and aquatic organisms, including seafood. So crude oil components or the detergent- and solvent-type components of dispersant, may not be toxic individually, but combined, impact long-term health. We’re trying to find out how that works, and we’re now trying to break apart the dispersant into its components and test new combinations of components.”
If you want to really see Spyropoulos light up, bring up how the researchers are doing just that by taking adult cells and making stem cells out of them. “The stem cells are seen as surrogates for fetal growth. We have whale, dolphin, alligator and human cells. We’ve focused on human health, but we need to know how these other top, trophic predators are faring as well, partly because we share common food sources with shared exposure histories,” he said.
Guillette said the problem with long-term studies or even large-scale studies based on epidemiological approaches in such a large area as was affected in the Gulf is the complexity of sorting out one factor – the oil spill – versus so many other factors affecting human health, such as smoking, diet and stress.
“We decided to use the power of in vitro systems and either stem cells or ‘engineered cells’ to approach the question of potential detrimental health effects.”
The lab groups of the four researchers have extensive experience working with engineered cells and using them to examine environmental factors. In this case, they are culturing engineered cells from humans and other organisms to determine if exposure to oil changes the fate of the cell.
“That is, can we change a cell’s fate by exposure to crude oil or dispersant or a mixture of components of the two?” Guillette said. “In our case, we are finding exposure to crude oil alters development so that stem cells are more likely to become fat cells versus bone or connective tissue. This has serious implications as the fate of these cells is critical for future embryonic health, and more fat cells lead to obesity.”
The researchers outlined a way they could test oil and oil components on surrogates for developing embryos without manipulating the embryos. They are using an “engineered cell” system that’s exciting in two ways, he said. It spares research animals’ lives, for one, given how the technology works, and it provides a high-end biotechnology model that can be used to test hundreds of substances to determine potency of suspected environmental contaminants, he said.
“We suspected that, like in a lot of environmental health studies, the developing embryo is a major target because it’s at a sensitive stage of development. We can’t expose human embryos –before we even get to exposing other kinds of embryos, we thought, there’s a mechanism that we can actually start to use, kind of this high-end biotechnology that we have to try and assess what’s going on.”
Guillette and his colleagues work closely with scientists at the Hollings Marine Laboratory (HML), including ones with The National Institute of Standards and Technology (NIST). “Because we also have NIST here and their principal chemists involved with analytical chemistry, we could marry this kind of world-class analytical chemistry with our biology.”
It’s been a formula for success in how the research is developing.
Guillette said if an embryo is exposed to certain compounds, its development will be altered and it may become predisposed to disease. “We are now collecting data. It took us a year to establish and validate our assays and approaches for use with crude oil and its fractions and the surfactants used during the oil spill. Early data suggests that there are components of crude oil – dispersant mixtures that are obesogenic – driving the fate of stem cells toward fat cells. Work over the next year or two will further these initial observations.”
Though the DWH spill provided the impetus for the current research, which is funded by the BP/The Gulf of Mexico Research Initiative, the results will go far beyond the spill.
“It accelerates the work in this area and fosters the science,” he said of the DWH spill research. “Here’s a component we use every day, and it’s forcing us to look in very different ways, at an oil spill, and because of its scale, because it was so massive, it demanded a massive response. There are tankers that hit shoals every day and spill 100,000 gallons of oil, and everybody goes ‘well that’s just modern society.’ But the fact is that oil has an impact on those systems and quite bluntly, we don’t understand them. We still don’t understand all the ramifications of Exxon Valdez, which was ‘just’ an oil spill off the Alaskan coast.”
Another beneficial effect is how the DWH research was put together so that scientists from different areas were encouraged to collaborate. Guillette said in his past 30 years experience as a scientist, he has found the greatest discoveries take place at the interfaces of science fields. When this kind of complex problem presents itself, that’s where the solutions will appear. The DWH spill is requiring people with different skill sets to work together to try and understand the impacts.
“Chemists can fractionate oil, but they can’t do what we do with those fractions in our engineered cells. By working together, we’re actually going to make much bigger discoveries, and that’s the model of the HML. All of the faculty members who are a part of the central mission of HML are, in fact, interested in that interface between environment and health. Whether it’s chemists, biologists, molecular biologists or managers who are trying to understand how you manage food or the other resources that the state is going to use, that’s how it all links together. That’s the bigger picture.”
Spyropoulos agrees, noting the wealth of individuals with warehouses of data, samples and technology at HML. “There’s a huge amount of measurements on toxic exposures in different regions and sentinel organisms. I can go and talk to a host of HML partners involved in water, sediment and marine organism tissue acquisition, contaminant analysis and fractionation, and they can tell me what I need to know. For example, if organisms in those areas carry such contamination, I can go to HML partners that have been conducting health assessments on coastal dolphins and get cells from individual dolphins that have been tracked since 2005.
“We have partners who can measure heavy metals, including the obesogen Trybutyltin used in antifouling paint – people who can measure these compounds with world expertise. If I want to make sense of huge amounts of data on mixtures of components of crude oil and dispersant, I can access HML partners’ ‘Machine Learning Tools,’” he said of an innovative research tool that interprets patterns in complex data that allows for the diverse stressors that occur in nature.
Guillette said all these researchers are tied together by the marine environment, where sentinel organisms, such as alligators and dolphins, reveal important clues about human health and the growing field of epigenetics. It’s why a place such as HML, with such diverse groups, has such cohesion. They all are tied together by a similar mantra.
“The mantra that we always have is, ‘if it’s not healthy for this organism living out there, it’s probably not healthy for us. If it’s not healthy for their kids, it’s probably not healthy for our kids.’ Now, is it always a one-to-one relationship? Of course not, but a red flag is a red flag. So if we’re seeing something going on in the environment, we have to ask is there something going on in ourselves?”
For more information on MUSC’s Marine Biomedicine and Environmental Sciences, visit its website.