Navigation Links
Biological selenium removal: The solution to pollution?
Date:9/15/2008

MADISON, WI, AUGUST 25, 2008 Selenium has been referred to as an "essential toxin" due to the fact that it shows only a marginal line between the nutritious requirement and toxic effects upon exposure. The steep dose response curve due to bioaccumulation effects have lead to the characterization of selenium as a "time bomb" that can be fused by exceeding a narrow threshold concentration in ecosystems through anthropogenic activities. Ironically, an estimated 0.5 to 1 billion people worldwide suffer from selenium deficiency, whereas areas of toxicity can be separated from selenium deficient areas by only 20 km.

The microbiological treatment of selenium - so called "dissimilatory metal reduction" - could supersede this problem, as selenium-reducing microorganisms are highly selective for selenate, reducing it to insoluble, less-toxic elemental selenium that can potentially be recovered from the process.

A study funded by the European Union, published in the September-October issue of the Journal of Environmental Quality, demonstrates that the biological treatment is indeed efficient for selenate reduction, and substantial amounts of selenate are converted to methylated selenium species or nano-sized elemental selenium particles. The emission of nano-sized selenium particles is problematic, as these can become bioavailable by direct assimilation or reoxidize to selenite and selenate. Dimethlyselenide and dimethyldiselenide, two species with unknown ecotoxicological long-term effects, contributed substantially to selenium dissolved in the effluent. Their formation was induced by minor temperature changes during biological reduction, thus a careful process control might drastically increase removal success of existing biotreatment systems for selenium and is a prerequisite for successful removal in full scale applications.

Consequently, remediative systems aiming at minimizing ecotoxicological risks on the one hand and selenium recovery and reuse on the other hand should be implemented. Due to the "high volume - low concentration" character, no sustainable solution has been found yet to treat selenium-contaminated drainage waters originating from the San Joachin Valley, one of the agriculturally most productive areas of the US (a comprehensive report by the USGS is available at http://pubs.usgs.gov/pp/p1646/pdf/pp1646.pdf).


'/>"/>

Contact: Sara Uttech
suttech@soils.org
608-268-4948
Soil Science Society of America
Source:Eurekalert

Related biology news :

1. Mate selection more biologically determined in some human populations
2. Interdisciplinary volume on biological rhythms serves as both primer and in-depth resource
3. Biological invasions increasing due to freshwater impoundments, says CU-Boulder study
4. Study shows more genes are controlled by biological clocks
5. Light receptors in eye play key role in setting biological clock, study shows
6. Francisella tularensis: Stopping a biological weapon
7. Tips on how to build a better home for biological parts
8. Genomics of large marine animals showcased in the biological bulletin
9. Securing the future of Europes biological data resources
10. Religion and the narrative of biological science
11. AIBS honors outstanding contributions to the biological sciences
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/20/2016)... Securus Technologies, a leading provider of ... safety, investigation, corrections and monitoring announced that after ... secured the final acceptance by all three (3) ... Systems (MAS) installed. Furthermore, Securus will have contracts ... by October, 2016. MAS distinguishes between legitimate wireless ...
(Date:6/9/2016)... Paris Police Prefecture ... solution to ensure the safety of people and operations in ... major tournament Teleste, an international technology group specialised ... today that its video security solution will be utilised by ... public safety across the country. The system roll-out is scheduled ...
(Date:6/2/2016)... --  The Weather Company , an IBM Business (NYSE: ... in which consumers will be able to interact with IBM ... voice or text and receive relevant information about the product ... have long sought an advertising solution that can create a ... and valuable; and can scale across millions of interactions and ...
Breaking Biology News(10 mins):
(Date:12/5/2016)... 5, 2016 According to ... by Products (Consumable, Instruments, Automated Cell Expansion System), ... Stem Cell Research, Cancer, and Cell-Based Research), End-users ... - Global Revenue, Trends, Growth, Share, Size and ... the global cell expansion market is expected to ...
(Date:12/5/2016)... /PRNewswire/ - Resverlogix Corp. ("Resverlogix" or the "Company") ... Safety Monitoring Board (DSMB) for the Company,s Phase ... patients has completed a second planned safety review ... planned without any modifications. The DSMB reviewed available ... efficacy concerns were identified. The DSMB will conduct ...
(Date:12/5/2016)... , Dec. 5, 2016  Eisai Inc. ... open-label two-year study of rufinamide, which were presented ... Epilepsy Society (AES) held from December 2-6 in ... final two-year safety, tolerability and cognitive data showed ... experienced similar safety and tolerability profiles, cognitive development ...
(Date:12/5/2016)... 2016 The U.S. Biotechnology industry ... billion of revenue and some $890 billion of total ... global biopharmaceuticals, and this figure is expected to exceed ... up these four equities for assessment: Northwest Biotherapeutics Inc. ... ACAD ), Acorda Therapeutics Inc. (NASDAQ: ...
Breaking Biology Technology: