Featured Research

from universities, journals, and other organizations

Natural dissolved organic matter plays dual role in cycling of mercury

Date:
January 13, 2011
Source:
DOE/Oak Ridge National Laboratory
Summary:
Nature has a bit of a Jekyll and Hyde relationship with mercury, but researchers have made a discovery that ultimately could help explain the split personality.

Findings published in Proceedings of the National Academy of Sciences by Oak Ridge National Laboratory's Liyuan Liang and Baohua Gu help explain previously reported seemingly contradictory findings.
Credit: ORNL photo by Jason Richards

Nature has a bit of a Jekyll and Hyde relationship with mercury, but researchers at the Department of Energy's Oak Ridge National Laboratory have made a discovery that ultimately could help explain the split personality.

While scientists have known that microbes in aquatic environments make methylmercury, a more toxic form of mercury that accumulates in fish, they also know that nature and other types of bacteria can transform methylmercury to less toxic forms. What they haven't completely understood are the mechanisms that cause these transformations in anoxic environments -- lacking in oxygen -- in nature.

"Until now, reactions between elemental mercury and dissolved organic matter have rarely been studied in anoxic environments," said Baohua Gu of the the lab's Environmental Sciences Division.

In a paper published in the Proceedings of the National Academy of Sciences, a team led by Gu reports that compounds from the decay of organic matter in aquatic settings affect mercury cycling. Low concentrations of these compounds can chemically reduce mercury, but as those concentrations increase, that reaction is greatly inhibited. They performed their experiments by simulating conditions found in nature.

"This study demonstrates that in anoxic sediments and water, organic matter is not only capable of reducing mercury, but also binding to mercury," said co-author Liyuan Liang. "This binding could make mercury less available to microorganisms for making methylmercury."

The authors also noted that their paper offers a mechanism that helps explain the seemingly contradictory reports on the interaction of organic matter and mercury in nature.

Gu and Liang hope this newly gained knowledge will play a role in helping to understand how mercury cycles in aquatic and sediment environments and help in informed decision-making for mercury-impacted sites around the nation.

"Our long-term goal is to understand the mechanisms controlling the production of methylmercury in the environment, " Liang said. "This understanding could lead to ways to reduce levels of mercury in fish as this is a global problem of enormous significance."

Mercury is distributed around the globe mainly through the burning of coal, industrial uses and through natural processes such as volcano eruptions. Various forms of mercury are widely found in sediments and water.

This research benefits from ORNL's expertise in field-to-laboratory geochemistry and microbiology, computational modeling and simulation, world-class neutron sources and high-performance computing.


Story Source:

The above story is based on materials provided by DOE/Oak Ridge National Laboratory. Note: Materials may be edited for content and length.


Journal Reference:

  1. B. Gu, Y. Bian, C. L. Miller, W. Dong, X. Jiang, L. Liang. Mercury reduction and complexation by natural organic matter in anoxic environments. Proceedings of the National Academy of Sciences, 2011; DOI: 10.1073/pnas.1008747108

Cite This Page:

DOE/Oak Ridge National Laboratory. "Natural dissolved organic matter plays dual role in cycling of mercury." ScienceDaily. ScienceDaily, 13 January 2011. <www.sciencedaily.com/releases/2011/01/110112160958.htm>.
DOE/Oak Ridge National Laboratory. (2011, January 13). Natural dissolved organic matter plays dual role in cycling of mercury. ScienceDaily. Retrieved August 21, 2014 from www.sciencedaily.com/releases/2011/01/110112160958.htm
DOE/Oak Ridge National Laboratory. "Natural dissolved organic matter plays dual role in cycling of mercury." ScienceDaily. www.sciencedaily.com/releases/2011/01/110112160958.htm (accessed August 21, 2014).

Share This




More Matter & Energy News

Thursday, August 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Flower Power! Dandelions Make Car Tires?

Flower Power! Dandelions Make Car Tires?

Reuters - Business Video Online (Aug. 20, 2014) Forget rolling on rubber, could car drivers soon be traveling on tires made from dandelions? Teams of scientists are racing to breed a type of the yellow flower whose taproot has a milky fluid with tire-grade rubber particles in it. As Joanna Partridge reports, global tire makers are investing millions in research into a new tire source. Video provided by Reuters
Powered by NewsLook.com
Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Newsy (Aug. 19, 2014) Scientists have developed a new device that mimics the way octopuses blend in with their surroundings to hide from dangerous predators. Video provided by Newsy
Powered by NewsLook.com
Researcher Testing on-Field Concussion Scanners

Researcher Testing on-Field Concussion Scanners

AP (Aug. 19, 2014) Four Texas high school football programs are trying out an experimental system designed to diagnose concussions on the field. The technology is in response to growing concern over head trauma in America's most watched sport. (Aug. 19) Video provided by AP
Powered by NewsLook.com
Green Power Blooms as Japan Unveils 'hydrangea Solar Cell'

Green Power Blooms as Japan Unveils 'hydrangea Solar Cell'

AFP (Aug. 19, 2014) A solar cell that resembles a flower is offering a new take on green energy in Japan, where one scientist is searching for renewables that look good. Duration: 01:29 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins