Cu and Zn concentration gradients created by dilution of pH neutral metal-spiked marine sediment: A comparison of sediment geochemistry with direct methods of metal addition
Author(s)
Hutchins, Colin M
Teasdale, Peter R
Lee, Shing Yip
Simpson, Stuart L
Year published
2008
Metadata
Show full item recordAbstract
The geochemistry of artificially metal contaminated sediments prepared using three methods of metal-spiking was compared in this study. Marine sediments with a gradient of Cu and Zn concentrations were prepared by direct-spiking without and with pH-adjustment to pH 7, and also by serial dilution of direct-spiked sediment (4000 姠g-1, pH 7 adjusted) with uncontaminated sediment. Porewater concentrations of Cu, Zn, Fe, and Mn in direct-spiked sediments without pH adjustment were orders of magnitude higher than the equivalent sediments adjusted to pH 7 or those prepared by the serial dilution method. Despite pH-adjustment, ...
View more >The geochemistry of artificially metal contaminated sediments prepared using three methods of metal-spiking was compared in this study. Marine sediments with a gradient of Cu and Zn concentrations were prepared by direct-spiking without and with pH-adjustment to pH 7, and also by serial dilution of direct-spiked sediment (4000 姠g-1, pH 7 adjusted) with uncontaminated sediment. Porewater concentrations of Cu, Zn, Fe, and Mn in direct-spiked sediments without pH adjustment were orders of magnitude higher than the equivalent sediments adjusted to pH 7 or those prepared by the serial dilution method. Despite pH-adjustment, porewater Cu and Zn concentrations of direct-spiked sediment remained higher than concentrations observed within metal-contaminated natural sediment. The serial dilution of metal-spiked, pH-adjusted sediment substantially decreased Cu and Zn partitioning to the dissolved phase, and minimized the variation of potential competitive ions (H+, Fe2+, Mn2+) over the entire gradient of spiked Cu and Zn concentrations. Metal concentration gradients created using serial dilution of Cu- and Zn-spiked, pH-adjusted sediments produced porewater Cu or Zn, Fe, and Mn concentrations that resemble sediment-porewater partitioning (Cu, Zn, Fe, Mn) typical of metal-contaminated natural sediments. This method is recommended for whole-sediment toxicology studies.
View less >
View more >The geochemistry of artificially metal contaminated sediments prepared using three methods of metal-spiking was compared in this study. Marine sediments with a gradient of Cu and Zn concentrations were prepared by direct-spiking without and with pH-adjustment to pH 7, and also by serial dilution of direct-spiked sediment (4000 姠g-1, pH 7 adjusted) with uncontaminated sediment. Porewater concentrations of Cu, Zn, Fe, and Mn in direct-spiked sediments without pH adjustment were orders of magnitude higher than the equivalent sediments adjusted to pH 7 or those prepared by the serial dilution method. Despite pH-adjustment, porewater Cu and Zn concentrations of direct-spiked sediment remained higher than concentrations observed within metal-contaminated natural sediment. The serial dilution of metal-spiked, pH-adjusted sediment substantially decreased Cu and Zn partitioning to the dissolved phase, and minimized the variation of potential competitive ions (H+, Fe2+, Mn2+) over the entire gradient of spiked Cu and Zn concentrations. Metal concentration gradients created using serial dilution of Cu- and Zn-spiked, pH-adjusted sediments produced porewater Cu or Zn, Fe, and Mn concentrations that resemble sediment-porewater partitioning (Cu, Zn, Fe, Mn) typical of metal-contaminated natural sediments. This method is recommended for whole-sediment toxicology studies.
View less >
Journal Title
Environmental Science & Technology
Volume
42
Issue
8
Publisher URI
Copyright Statement
© 2008 American Chemical Society. Self-archiving of the author-manuscript version is not yet supported by this publisher. Please refer to the journal link for access to the definitive, published version or contact the authors for more information.