The effect of membrane filtration on dissolved trace element concentrations |
| |
Authors: | Arthur J. Horowitz Ken R. Lum John R. Garbarino Gwendy E. M. Hall Claire Lemieux Charles R. Demas |
| |
Affiliation: | 1. U.S. Geological Survey, Peachtree Business Center, 3039 Amwiler Road, 30360, Atlanta, GA, USA 2. Centre Saint-Laurent, Environment Canada, H2Y2E7, Montreal, Quebec, Canada 4. U.S. Geological Survey, Branch of Analytical Services, 5293 Ward Road, 80002, Arvada, CO, USA 5. Geological Survey of Canada, 601 Booth Street, KIA OE8, Ottawa, Ontario, Canada 7. U.S. Geological Survey, 3535 S. Sherwood Forest Blvd., Suite 120, 70816, Baton Rouge, LA, USA
|
| |
Abstract: | The almost universally accepted operational definition for dissolved constituents is based on processing The almost universally accepted operational definition for dissolved constituents is based on processing whole-water samples through a 0.45-μm membrane filter. Results from field and laboratory experiments indicate that a number of factors associated with filtration, other than just pore size (e.g., diameter, manufacturer, volume of sample processed, amount of suspended sediment in the sample), can produce substantial variations in the ‘disolved’ concentrations of such elements as Fe, Al, Cu, Zn, Pb, Co, and Ni. These variations result from the inclusion/exclusion of colloidally-associated trace elements. Thus, 'dissolved' concentrations quantitated by analyzing filtrates generated by processing whole-water through similar pore-sized membrane filters may not be equal/comparable. As such, simple filtration through a 0.45-μm membrane filter may no longer represent an acceptable operational definition for dissolved chemical constituents. This conclusion may have important implications for environmental studies and regulatory agencies. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|