Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A Different Kind of Mine Disaster

14.04.2010
The world's largest antimony mine has become the world's largest laboratory for studying the environmental consequences of escaped antimony -- an element whose environmental and biological properties are still largely a mystery.

"Antimony is an emergent contaminant," said IU Bloomington Ph.D. student Faye Liu, the paper's lead author. "People have not paid enough attention to it."

Used in small quantities, antimony has a wide variety of applications -- from hardening the lead in bullets and improving battery performance to combating malaria.

Little is known about antimony's toxicity, in part because the metalloid element is usually found at low, parts-per-billion concentrations in natural environments. At Xikuangshan, Liu and her colleagues found that aqueous antimony concentrations could be as high 11 parts per million, 1,000 times the antimony levels found in uncontaminated water.

The alarming circumstances at Xikuangshan present an opportunity to understand what happens to antimony, geologically and chemically, when large quantities of it are introduced to the environment. That knowledge will be useful to investigations of antimony contamination near factories and military bases around the world.

The U.S. Environmental Protection Agency and similar regulatory agencies in Europe operate under the assumption that antimony's properties are similar to those of arsenic, another element in antimony's chemical group.

"That will need to change," said IU Bloomington geologist Chen Zhu, Liu's advisor and the project's principal investigator. "We saw that antimony behaves very differently from arsenic -- antimony oxidizes much more quickly than arsenic when exposed."

The vast majority of antimony the scientists isolated at Xikuangshan was of the "V" type, an oxidation state in which the metal has given up five electrons. It is believed V is the least toxic of the three oxidation states of which antimony is capable (I, III and V). It is not known whether antimony-V's relatively diminished toxicity is upended at Xikuangshan by its overwhelming presence.

Land within and around the mining area is used for farming. The drinking water plant for local residents was built in the mining area. Zhu says health problems are common at Xikuangshan, possibly the result of antimony intoxication.

Zhu says he is discussing a possible collaboration with IU School of Medicine toxicologist Jim Klaunig. Researchers would return to Xikuangshan to determine whether the elevated antimony can be tied to acute and chronic health problems among those who live in the vicinity. Another possible study group might be those Chinese who live downstream of Xikuangshan along the Qing River.

As part of their Environmental Geochemistry and Health study, Zhu and scientists from the Chinese Academy of Sciences conducted field work at Xikuangshan in 2007, drawing multiple water samples from 18 different sample sites. Samples were shipped back to Bloomington for atomic fluorescence spectroscopic analysis and to Alberta for inductively coupled plasma mass spectroscopy analysis. The scientists learned antimony-III was rare, beyond detection or present at trace levels. The near totality of antimony in each water sample was antimony-V.

The Xikuangshan antimony mine is the world's largest. Since antimony mining began there more than 200 years ago, mine production has increased steadily to the present day. Today, Xikuangshan produces 60 percent of the world's antimony.

While Zhu was on sabbatical leave in 2008, Faye Liu was advised by IU Bloomington biogeochemist and inaugural Provost's Professor Lisa Pratt. Zhu and Pratt recently began a joint project to learn more about the biogeochemistry of antimony. The scientists' antimony research complements their concurrent NSF-funded research on arsenic.

IU Bloomington geologists Claudia Johnson and Erika Elswick, both participants in the Environmental Geochemistry and Health study, have also taken seawater samples from the Caribbean. Liu is investigating the samples' antimony content.

Also contributing to the research were University of Alberta environmental toxicologist X. Chris Le and his students, Anthony McKnight-Whitford (Ph.D.) and Yunlong Xia (M.S.), and Chinese Academy of Sciences geochemist Fengchang Wu. The research was supported by the China Scholarship Council and Indiana University.

To speak with Zhu or Liu, please contact David Bricker, University Communications, at 812-856-9035 or brickerd@indiana.edu.

"Antimony speciation and contamination of waters in the Xikuangshan antimony mining and smelting area, China," Environmental Geochemistry and Health, by Faye Liu, X. Chris Le, Anthony McKnight-Whitford, Yunlong Xia, Fengchang Wu, Erika Elswick, Claudia C. Johnson, and Chen Zhu (early access online)

David Bricker | Newswise Science News
Further information:
http://www.indiana.edu

More articles from Earth Sciences:

nachricht Geophysicists and atmospheric scientists partner to track typhoons' seismic footprints
16.02.2018 | Princeton University

nachricht NASA finds strongest storms in weakening Tropical Cyclone Sanba
15.02.2018 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Rare find from the deep sea

20.02.2018 | Life Sciences

In living color: Brightly-colored bacteria could be used to 'grow' paints and coatings

20.02.2018 | Life Sciences

Observing and controlling ultrafast processes with attosecond resolution

20.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>