New technique put to use to test clean up of contaminated groundwater

Jan 30, 2009

Cleaning up the dangerous contaminants — dry-cleaning fluids, solvents and petroleum hydrocarbons — found in underground water presents one of the most urgent challenges facing environmental science. A report issued today by the U.S. Environmental Protection Agency (EPA) sheds light on a new way to monitor and improve the success of clean-up efforts using a technique developed at the University of Toronto.

"The most common method to clean-up groundwater is biodegradation — using microbes to consume the contaminants and break them down into more benign end products that are not harmful to the environment," says U of T geochemist Barbara Sherwood Lollar, the scientist who initiated the concept and goals for the EPA report and is one of its five international authors.

The report outlines how this can be done using a novel technique called Compound Specific Isotope Analysis, developed in U of T's Stable Isotope Laboratory. The elements of carbon that form the basis for the hydrocarbon contaminants actually come in two types called isotopes, explains Sherwood Lollar. "When microbes degrade contaminants, they prefer the lighter isotope carbon 12 over the heavier isotope carbon 13. The resulting change in the ratio of these isotopes in the contaminant itself is a dramatic and definitive indicator that the biodegradation is successfully taking place."

Beginning in the 1990s, U of T's Stable Isotope Laboratory has been an international pioneer in discovering how different carbon isotopes can be used to identify whether or not biodegradation is taking place. "Today, dozens of students in Canada have been trained in this method, drawn in by the fascinating combination of fundamental research that has important applications such as the clean-up of drinking water," says Sherwood Lollar. Over the past decade, as the new technique has become more widespread, centres for research and education —- and even private companies — have blossomed worldwide.

"Much of the research on new methods of analyzing groundwater contamination has been published in scientific and professional journals but this report — written specifically for the practitioners in accessible language with clear procedural information and decision-making strategies — is a milestone," says Sherwood Lollar.

"It is particularly gratifying to be able to take a technique out of the lab and to put it into the hands of the people working on this issue every day around the world," she says.

Source: University of Toronto

Explore further: Five anthropogenic factors that will radically alter northern forests in 50 years

add to favorites email to friend print save as pdf

Related Stories

Meteorites yield clues to Martian early atmosphere

2 hours ago

(Phys.org) —Geologists who analyzed 40 meteorites that fell to Earth from Mars unlocked secrets of the Martian atmosphere hidden in the chemical signatures of these ancient rocks. Their study, published ...

Decline of Bronze Age 'megacities' linked to climate change

Feb 26, 2014

Scientists from the University of Cambridge have demonstrated that an abrupt weakening of the summer monsoon affected northwest India 4,100 years ago. The resulting drought coincided with the beginning of the decline of the ...

Scientists blend synthetic air to measure climate change

Feb 26, 2014

Scientists at the National Physical Laboratory (NPL) have produced a synthetic air reference standard which can be used to accurately measure levels of carbon dioxide and methane in the atmosphere. This will ...

Recommended for you

New research on Earth's carbon budget

10 hours ago

(Phys.org) —Results from a research project involving scientists from the Desert Research Institute have generated new findings surrounding some of the unknowns of changes in climate and the degree to which ...

User comments : 0

More news stories

Magnitude-7.2 earthquake shakes Mexican capital

A powerful magnitude-7.2 earthquake shook central and southern Mexico on Friday, sending panicked people into the streets. Some walls cracked and fell, but there were no reports of major damage or casualties.

Treating depression in Parkinson's patients

A group of scientists from the University of Kentucky College of Medicine and the Sanders-Brown Center on Aging has found interesting new information in a study on depression and neuropsychological function in Parkinson's ...