Chemicals used as flame retardants are present as environmental pollutants at locations around the globe, including remote sites in Indonesia, Nepal and Tasmania, according to a study by researchers from the Indiana University School of Public and Environmental Affairs.
The study, published this month in the journal Environmental Science and Technology, makes use of a novel but highly effective sampling technique: measuring concentrations of the chemicals in the bark of trees, which absorbs compounds in both vapor and particle phases.
"These findings illustrate further that flame retardants are ubiquitous pollutants and are found all around the world, not only in biota and humans but also in plants," said Amina Salamova, a research associate in the School of Public and Environmental Affairs at IU Bloomington and co-author of the study with Ronald A. Hites, Distinguished Professor in SPEA and in the Department of Chemistry in the College of Arts and Sciences.
The study measured concentrations of brominated and chlorinated flame retardants collected in tree bark samples at 12 locations around the globe: three sites in Canada and single sites in Iceland, Ireland, Norway, Czech Republic, South Africa, Nepal, Indonesia, Tasmania and American Samoa.
The highest concentrations were found at an urban site: Downsview, Ontario, Canada, near Toronto. However, the second-highest concentration of one type of flame retardant, Dechlorane Plus, was found at a remote site at Bukit Kototabang in Indonesia. Researchers don't know the cause of the relatively high concentrations at the site but suspect it may be near a source.
The study was carried out in cooperation with the Global Atmospheric Passive Sampling network, an international monitoring initiative established in 2004 on six continents.
Brominated and chlorinated flame retardants have been used for several decades in consumer products made of plastic, foam, wood and textiles to prevent combustion and slow the spread of fire. They persist in the environment and bio-accumulate in ecosystems and in human tissues. Exposure to the compounds has been associated with thyroid and other endocrine system disruption and with adverse neurological development. As a result, the production and use of certain flame retardants has been restricted in North America and the European Union.
Researchers measured a variety of flame retardants, including widely used polybrominated diphenyl ethers, or PBDE, as well as nonregulated compounds such as Dechlorane Plus and "older" flame retardants that were used in the 1980s. Findings included:
Most of the compounds were detected at all the locations, with concentrations varying widely.
Concentrations were associated with population density, suggesting the compounds most likely entered the environment through their use in nearby homes and offices.
Concentrations found in tree bark are correlated with those measured in previous atmospheric sampling at the sites by the Global Atmospheric Passive Sampling network.
Higher concentrations of flame retardants in bark and the atmosphere have been found by Hites and others in previous studies of the Great Lakes region, especially urban areas near Chicago and Cleveland, and also at cities in China. Even higher concentrations were found in southern Arkansas and at Niagara Falls, N.Y., near the sites of manufacturing facilities for PBDE and Dechlorane Plus, respectively.
The study also confirms the effectiveness of using tree bark as a sampling medium, a technique that Hites and colleagues have used in previous studies of persistent organic pollutants such as flame retardants.
Bark makes an effective sampling medium because of its large surface area and high lipid content. The samples are easy and inexpensive to collect, an advantage in developing countries that lack funding for extensive environmental monitoring programs. Tree bark also collects both vapor and particle phase pollutants, while other samplers collect one or the other.
Support for the study came from the Great Lakes National Program Office of the U.S. Environmental Protection Agency. The article is available online. To speak with Salamova or Hites, contact Steve Hinnefeld at IU Communications, 812-856-3488 or email@example.com, or Jim Hanchett at the School of Public and Environmental Affairs, 812-856-5490 or firstname.lastname@example.org
Steve Hinnefeld | EurekAlert!
Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel
Oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”
05.07.2018 | European Geosciences Union
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
18.07.2018 | Materials Sciences
18.07.2018 | Life Sciences
18.07.2018 | Health and Medicine