Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

U of M study finds rising levels of dioxins from common soap ingredient in Mississippi River sediments

19.05.2010
Dioxins in general decreasing, but those derived from triclosan increasing

Specific dioxins derived from the antibacterial agent triclosan, used in many hand soaps, deodorants, dishwashing liquids and other consumer products, account for an increasing proportion of total dioxins in Mississippi River sediments, according to University of Minnesota research.

The study appears online in the May 18 issue of the journal Environmental Science and Technology.

The researchers, from the university's Institute of Technology (soon to be College of Science and Engineering), found that over the last 30 years, the levels of the four dioxins derived from triclosan have risen by 200 to 300 percent, while levels of all the other dioxins have dropped by 73 to 90 percent.

In April, the Food and Drug Administration announced it would study the safety of triclosan, which has been linked to disruptions of hormonal function and may also play a role in the evolution of bacterial resistance to antibiotics. In papers published in 2003 and 2009, university civil engineering professor William Arnold and his colleague Kristopher McNeill, a former professor in the university's Department of Chemistry, discovered that triclosan, when exposed to sunlight, generated a specific suite of four dioxins.

In the current study spearheaded by Jeff Buth, a recent Ph.D. graduate in chemistry (supervised by Arnold and McNeill), the researchers examined sediment core samples from Lake Pepin, an enlargement of the Mississippi River 120 miles downstream from the Minneapolis-St. Paul metro area. The sediment cores, containing a record of pollutant accumulation in the lake for the past 50 years, were analyzed for triclosan, the four dioxins derived from triclosan, and the entire family of dioxin chemicals. The study was a collaborative effort between researchers at the University of Minnesota, Pace Analytical (Minneapolis), the Science Museum of Minnesota and Virginia Tech.

“These four dioxins only come from triclosan. They didn’t exist in Lake Pepin before triclosan was introduced,” Arnold said. “In the most current sediments, these triclosan-derived dioxins account for about 30 percent of the total dioxin mass.”

Triclosan was first added to commercial liquid hand soap in 1987, and by 2001 about 76 percent of commercial liquid hand soaps contained it, researchers say. About 96 percent of triclosan from consumer products is disposed of in residential drains, leading to large loads of the chemical in water entering wastewater treatment plants.

Triclosan is incompletely removed during the wastewater treatment process, and when treated wastewater is released to the environment, sunlight converts some of the triclosan (and related compounds) into dioxins. Triclosan and the dioxins ended up in Lake Pepin sediments by sticking to organic particles in the river, which then sank when they reached the calmer waters of the lake.

The toxicity of the dioxins derived from triclosan currently is not well understood, nor is the extent of their distribution in the environment at large, Arnold says.

To read the complete study, visit http://pubs.acs.org/doi/abs/10.1021/es1001105

Ryan Maus | EurekAlert!
Further information:
http://www.umn.edu

More articles from Ecology, The Environment and Conservation:

nachricht Upcycling 'fast fashion' to reduce waste and pollution
03.04.2017 | American Chemical Society

nachricht Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

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: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>