Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Pollutants could pose health risks for 5 sea turtle species

29.06.2012
Researchers at the Hollings Marine Laboratory (HML) and four partner organizations have measured for the first time concentrations of 13 perfluoroalkyl compounds (PFCs) in five different endangered species of sea turtles.

While PFC toxicology studies have not yet been conducted on turtles, the levels of the compounds seen in all five species approach the amounts known to cause adverse health effects in other animals.

PFCs are man-made compounds that have many uses including stain-resistant coatings, fire-fighting foams and emulsifiers in plastics manufacturing. They have become widespread pollutants, are detectable in human and wildlife samples worldwide, infiltrate food chains, and have been shown in laboratory animals—rats, mice and fish—to be toxic to the liver, the thyroid, neurobehavioral function and the immune system. The PFCs most commonly found in the environment are perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA).

Located in Charleston, S.C., the HML is a collaboration of the National Institute of Standards and Technology (NIST), the National Oceanic and Atmospheric Administration (NOAA), the South Carolina Department of Natural Resources, the College of Charleston and the Medical University of South Carolina.

"In our experiment, we wanted to accomplish two goals," says NIST research biologist and study lead Jennifer Keller. "We wanted to get the first accurate measurements of the plasma blood concentrations of PFCs in five sea turtle species across different trophic [food chain] levels, and then compare those concentrations to ones known to cause toxic effects in laboratory animals. That way, we could estimate the potential health risks from PFC exposure for all five turtles."

The five sea turtle species studied were the green, hawksbill, leatherback, loggerhead and Kemp's ridley. Their preferred diets range up the food chain from the green's sea grasses and algae to the crabs favored by the Kemp's ridley. The researchers expected that the PFC concentrations would be higher in species that fed farther up the food chain, since their prey's tissues would probably concentrate the pollutants.

This was generally the case. Plant-eating green turtles had the lowest plasma concentrations for the majority of PFCs examined, especially PFOS. As expected, leatherbacks, loggerheads and Kemp's ridleys had progressively higher PFOS concentrations. Surprisingly, however, hawksbills—who browse low on the food chain, primarily on sponges—recorded the second-highest average concentration of PFOS and were the only species to have a detectable PFOA level. The researchers surmise that this may relate to the locations where the hawksbills forage, or it may suggest that sponges have unusually high concentrations of PFOS and PFOA.

In the second part of the study, Keller and her colleagues compared the plasma concentrations of PFOS that they found in the five sea turtle species with previously reported concentrations that were shown to have adverse health effects in laboratory animals. The results showed that hawksbills, loggerheads and Kemp's ridleys had PFOS concentrations approaching those linked to liver and neurobehavioral toxicity in other animals; levels in loggerheads and Kemp's ridleys approached those linked to thyroid disruption in other animals; and all five species had levels that approached those linked to suppressed immunity in other animals.

"Better understanding the threat of PFCs, especially PFOS, to sea turtles can help wildlife managers and others develop strategies to deal with potential health problems," Keller says. "Our study provides the first baseline data in this area but more research is needed—especially for hawksbills after seeing their unexpectedly high PFC exposure."

Researchers from the College of Charleston's Grice Marine Laboratory, NOAA's National Marine Fisheries Service and the Loggerhead Marinelife Center also contributed to the study.

* J.M. Keller, L. Ngai, J.B. McNeill, L.D. Wood, K.R. Stewart, S.G. O'Connell and J.R. Kucklick. Perfluoroakyl contaminants in plasma of five sea turtle species: Comparisons in concentration and potential health risks. Environmental Toxicology and Chemistry, Vol. 31, No. 6, pp. 1223-1230 (June 2012). DOI: 10.1002/etc.1818

Michael E. Newman | EurekAlert!
Further information:
http://www.nist.gov

More articles from Ecology, The Environment and Conservation:

nachricht Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen

nachricht A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde

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: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>