Navigation Links
ORNL scientists hone technique to safeguard water supplies
Date:8/28/2009

OAK RIDGE, Tenn., Aug. 28, 2009 A method to detect contaminants in municipal water supplies has undergone further refinements by two Oak Ridge National Laboratory researchers whose findings are published on line in Water Environment Research.

The new work demonstrates that the technology that uses algae as sentinels has broader applications than previously reported, according to authors Miguel Rodriguez Jr. and Elias Greenbaum of the Department of Energy's ORNL. For example, under real-world operating conditions, the sensitivity of the algae to toxins has a natural daily cycle that tracks the sun.

"When the sun is overhead and shining brightly, the algae are less sensitive to the toxins," Greenbaum said. "The new work shows that keeping the water sample in darkness for about 30 minutes prior to testing for toxins restores full sensitivity to the test."

The new results also show that the technology can be applied to many different water quality environments such as when the algae are starved for nutrients.

"Our key result is that despite real-world conditions that create challenges, free-living microalgae combined with 'work-around' strategies can be used as broad-spectrum automated biosensor systems for continuous monitoring of source drinking water," Greenbaum said.

The process uses a fluorometer to measure the fluorescence signal of algae that grow naturally in source water such as Tennessee's Clinch River, which was used in this study. Researchers exploit the known characteristics of Photosystems I and II, which convert light energy into chemical energy, to detect any changes in the process of photosynthesis.

"Recent advances in optoelectronics and portability make this a powerful technology for monitoring the in situ physiology of aquatic photosynthetic organisms such as green algae and cyanobacteria," the authors wrote. Even low levels of toxins alter fluorescence patterns within minutes.

Another significant aspect of this work is the reporting of statistically reliable data on the threshold detection levels for broad classes of toxins such as blood and nerve agents and agrochemicals. These levels are at or near Environmental Protection Agency regulatory guidelines, Greenbaum said.

For this study, the researchers looked at five classes of chemical agents in water: Diuron, atrazine, paraquat, methyl parathion and potassium cyanide. All are known to be harmful to human health. In the case of Diuron, used in agriculture for 50 years, Greenbaum and Rodriguez were able to detect 1 part per million. This was indicated by a 17 percent decline in the algae's Photosystem II efficiency.

"We have shown that microalgae in source drinking water can be used as broad-spectrum, robust sentinel sensors to detect relatively low concentrations of toxins," Greenbaum said. "We have also shown that the microalgae do not need to be in an optimized state for this technology to be effective."


'/>"/>

Contact: Ron Walli
wallira@ornl.gov
865-576-0226
DOE/Oak Ridge National Laboratory
Source:Eurekalert

Related biology news :

1. UK scientists working to help cut ID theft
2. Scientists show that mitochondrial DNA variants are linked to risk factors for type 2 diabetes
3. Comet probes reveal evidence of origin of life, scientists claim
4. Scientists link fragile X tremor/ataxia syndrome to binding protein in RNA
5. Male elephants get photo IDs from scientists
6. Scientists retrace evolution with first atomic structure of an ancient protein
7. Muscle mass: Scientists identify novel mode of transcriptional regulation during myogenesis
8. Carnegie Mellon scientists develop nanogels that enable controlled delivery of carbohydrate drugs
9. Clemson scientists shed light on molecules in living cells
10. Scientists tackle mystery mountain illness
11. T. rex quicker than Becks, say scientists
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/21/2016)... , June 21, 2016 NuData ... the new role of principal product architect and ... the director of customer development. Both will report ... technical officer. The moves reflect NuData,s strategic growth ... response to high customer demand and customer focus ...
(Date:6/9/2016)... an innovation leader in attendance control systems is proud to announce the introduction of ... make sure the right employees are actually signing in, and to even control the ... ... ... ...
(Date:6/2/2016)... 2, 2016 The Department of Transport ... the 44 million US Dollar project, for the , ... including Personalization, Enrolment, and IT Infrastructure , to ... production and implementation of Identity Management Solutions. Numerous renowned international ... Decatur was selected for the most compliant ...
Breaking Biology News(10 mins):
(Date:12/2/2016)... ... , ... DrugDev believes the only way to achieve real change ... three tenets were on display at the 2nd Annual DrugDev User Summit (hosted by ... and site organizations to discuss innovation and the future of clinical research. , ...
(Date:12/2/2016)... December 2, 2016 The immunohistochemistry (IHC) ... at a CAGR of 7.3% during the forecast period of 2016 ... diagnostic laboratories segment accounted for the largest share of immunohistochemistry (IHC) ... , ... global immunohistochemistry (IHC) market spread across 225 pages, profiling 10 companies ...
(Date:11/30/2016)... TORONTO , Nov. 30, 2016 /PRNewswire/ - Portage ... Canadian Securities Exchange: PBT.U), is excited to announce ... company focused on developing preclinical ophthalmology assets through ... a potent anti-inflammatory created by Portage Pharmaceuticals Limited ... patients with ocular surface and anterior segment diseases. ...
(Date:11/30/2016)... BEIJING , Nov. 30, 2016 Novogene ... services and solutions with cutting edge next-generation sequencing (NGS) ... a USD $75 Million [515 Million RMB] B round ... Capital Management ( Shenzhen ) Co., Ltd. ... Innovation") and Shanghai Sigma Square Investment Center LP ("Sigma ...
Breaking Biology Technology: