Featured Research

from universities, journals, and other organizations

New low-cost, nondestructive technology cuts risk from mercury hot spots

Date:
October 25, 2013
Source:
Smithsonian
Summary:
Hot spots of mercury pollution in aquatic sediments and soils can contaminate local food webs and threaten ecosystems, but cleaning them up can be expensive and destructive. Researchers have found a new low-cost, nonhazardous way to reduce the risk of exposure: using charcoal to trap it in the soil.

Upal Ghosh (UMBC) spreading SediMite.
Credit: Cynthia Gilmour, Smithsonian Environmental Research Center

Hot spots of mercury pollution in aquatic sediments and soils can contaminate local food webs and threaten ecosystems, but cleaning them up can be expensive and destructive. Researchers from the Smithsonian Environmental Research Center and the University of Maryland, Baltimore County have found a new low-cost, nonhazardous way to reduce the risk of exposure: using charcoal to trap it in the soil.

Mercury-contaminated "Superfund sites" contain some of the highest levels of mercury pollution in the U.S., a legacy of the many industrial uses of liquid mercury. But despite the threat, there are few available technologies to decrease the risk, short of digging up the sediments and burying them in landfills -- an expensive process that can cause significant ecological damage.

In a new study published in the journal Environmental Science & Technology, Cynthia Gilmour (SERC), Upal Ghosh (UMBC) and their colleagues show that adding activated carbon, a form of charcoal processed to increase its ability to bind chemicals, can significantly reduce mercury exposure in these highly contaminated sites. With funding and support from several industry and federal partners, the team tested the technology in the laboratory with mercury-contaminated sediments from four locations: a river, a freshwater lake and two brackish creeks. To reduce the harm from mercury, the sorbents also had to decrease the amount of methylmercury taken up by worms.

"Methylmercury is more toxic and more easily passed up food webs than inorganic mercury," said Gilmour, the lead author on the study. "Unfortunately, methylmercury is produced from mercury contamination by natural bacteria. To make contaminated sites safe again, we need to reduce the amount of methylmercury that gets into animals."

Added at only 5 percent of the mass of surface sediments, activated carbon reduced methylmercury uptake by sediment-dwelling worms by up to 90 percent. "This technology provides a new approach for remediation of mercury-contaminated soils -- one that minimizes damage to contaminated ecosystems, and may significantly reduce costs relative to digging or dredging," said Ghosh, co-author on the study. Activated carbon can be spread on the surface of a contaminated sediment or soil, without physical disturbance, and left in place to mix into the sediment surface. Called "in-situ remediation," the use of sorbents like activated carbon has been proven to reduce the uptake of several other toxic pollutants. However, this is the first time activated carbon had been tested for mercury-contaminated soils.

The research group is now testing its effectiveness in the field at several Superfund sites across the country. If successful in the field, this approach of treating soil with activated carbon may be able to reduce the risk of mercury exposure in polluted sites and subsequent contamination of food webs.


Story Source:

The above story is based on materials provided by Smithsonian. Note: Materials may be edited for content and length.


Journal Reference:

  1. Cynthia C. Gilmour, Georgia S. Riedel, Gerhardt Riedel, Seokjoon Kwon, Richard Landis, Steven S. Brown, Charles A. Menzie, and Upal Ghosh. Activated Carbon Mitigates Mercury and Methylmercury Bioavailability in Contaminated Sediments. Environmental Science & Technology, 2013 DOI: 10.1021/es4021074

Cite This Page:

Smithsonian. "New low-cost, nondestructive technology cuts risk from mercury hot spots." ScienceDaily. ScienceDaily, 25 October 2013. <www.sciencedaily.com/releases/2013/10/131025091940.htm>.
Smithsonian. (2013, October 25). New low-cost, nondestructive technology cuts risk from mercury hot spots. ScienceDaily. Retrieved August 1, 2014 from www.sciencedaily.com/releases/2013/10/131025091940.htm
Smithsonian. "New low-cost, nondestructive technology cuts risk from mercury hot spots." ScienceDaily. www.sciencedaily.com/releases/2013/10/131025091940.htm (accessed August 1, 2014).

Share This




More Earth & Climate News

Friday, August 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Visitors Feel Part of the Pack at Wolf Preserve

Visitors Feel Part of the Pack at Wolf Preserve

AP (July 31, 2014) Seacrest Wolf Preserve on the northern Florida panhandle allows more than 10,000 visitors each year to get up close and personal with Arctic and British Columbian Wolves. (July 31) Video provided by AP
Powered by NewsLook.com
Florida Panther Rebound Upsets Ranchers

Florida Panther Rebound Upsets Ranchers

AP (July 31, 2014) With Florida's panther population rebounding, some ranchers complain the protected predators are once again killing their calves. (July 31) Video provided by AP
Powered by NewsLook.com
Big Waves In Arctic Ocean Threaten Polar Ice

Big Waves In Arctic Ocean Threaten Polar Ice

Newsy (July 30, 2014) Big waves in parts of the Arctic Ocean are unprecedented, mainly because they used to be covered in ice. Video provided by Newsy
Powered by NewsLook.com
Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
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