For nearly four decades, scientists have suspected that persistent organic pollutants (POPs) contributed to a green turtle's susceptibility to the virus that causes fibropapilomatosis (FP), a disease that forms large benign tumors that can inhibit the animal's sight, mobility and feeding ability.
In a new study,* researchers from the Hollings Marine Laboratory (HML), a government-university partner facility in Charleston, S.C., and from university and federal collaborators in Hawaii demonstrated POPs are not, in fact, a co-factor linked to the increasing number of green sea turtles afflicted with FP.
POPs are a large group of man-made chemicals that, as their name indicates, persist in the environment. They also spread great distances through air and water, accumulate in human and animal tissues, increase in concentration up food chains, and may have carcinogenic and neurodevelopmental effects.
POPs include banned substances such as DDT and toxaphenes, once used as pesticides; polychlorinated biphenyls (PCBs), once used as insulating fluids; and polybrominated diphenyl ethers (PDBEs), still used as flame retardants. Two previous studies attempting to link POPs and FP were unable to rule out the impact of the pollutants on the disease.
"We wanted to do a thorough study looking at a large, statistically valid population of turtles and using methods that could detect even tiny levels of POPs in their tissues," says National Institute of Standards and Technology (NIST) research biologist Jennifer Keller, lead author on the paper appearing in the journal Environmental Science and Technology.
Keller and her colleagues collected turtle blood samples at four locations across Hawaii, each one having a different prevalence of FP—none, low, moderate and high—in the marine turtle population residing there. "We analyzed the plasma for 164 different organic compounds to see if POP concentrations increased with increasing prevalence of FP," Keller says. "We also looked at the levels of halogenated phenols, chemicals which can come from either man-made [POP] sources or naturally from the green turtle's main food source, marine algae."
The researchers discovered that increasing POP concentrations did not correspond with a like rise in the numbers of FP tumors observed. "Our findings show that POPs are not the trigger for FP, so we can eliminate these pollutants from future studies trying to explain why the disease is more common in certain areas or why its prevalence is changing with time," Keller says.
As for halogenated phenols, the team found that the sampled turtles did have detectable concentrations of the compounds. "While it's a novel discovery for sea turtles, we believe that these phenols are likely from the turtle's diet of algae rather than man-made POPs," Keller explains.
Collaborating with Keller were researchers from Hawaiian branches of two federal agencies, the National Marine Fisheries Service and the U.S. Geological Survey, as well as from Hawaii Pacific University and the Hawaii Preparatory Academy.
The HML is a unique partnership of governmental and academic organizations including NIST, NOAA's National Ocean Service, the South Carolina Department of Natural Resources, the College of Charleston and the Medical University of South Carolina.
*J.M. Keller, G.H. Balazs, F. Nilsen, M. Rice, T.M. Work and B.A. Jensen. Investigating the potential role of persistent organic pollutants in Hawaiian green sea turtle fibropapillomatosis. Environmental Science and Technology. Accepted for publication June 25, 2014, DOI: 10.1021/es5014054
Michael E. Newman | Eurek Alert!
New switch decides between genome repair and death of cells
27.09.2016 | University of Cologne - Universität zu Köln
A blue stoplight to prevent runaway photosynthesis
27.09.2016 | National Institute for Basic Biology
Friction stir welding is a still-young and thus often unfamiliar pressure welding process for joining flat components and semi-finished components made of light metals.
Scientists at the University of Stuttgart have now developed two new process variants that will considerably expand the areas of application for friction stir welding.
Technologie-Lizenz-Büro (TLB) GmbH supports the University of Stuttgart in patenting and marketing its innovations.
Friction stir welding is a still-young and thus often unfamiliar pressure welding process for joining flat components and semi-finished components made of...
Optical quantum computers can revolutionize computer technology. A team of researchers led by scientists from Münster University and KIT now succeeded in putting a quantum optical experimental set-up onto a chip. In doing so, they have met one of the requirements for making it possible to use photonic circuits for optical quantum computers.
Optical quantum computers are what people are pinning their hopes on for tomorrow’s computer technology – whether for tap-proof data encryption, ultrafast...
The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.
“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...
With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.
Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...
For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.
Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...
28.09.2016 | Event News
27.09.2016 | Event News
23.09.2016 | Event News
28.09.2016 | Medical Engineering
28.09.2016 | Materials Sciences
28.09.2016 | Business and Finance