Chemical availability of cadmium in Mississippi River sediment

Journal Article · Thu Oct 01 04:00:00 EDT 1981 · J. Environ. Qual.; (United States)

DOI:https://doi.org/10.2134/jeq1981.00472425001000040021x· OSTI ID:5929179

Khalid, R A; Gambrell, R P; Patrick, W H

There is concern that changes in the physiochemical conditions occurring during dredging and disposal of polluted sediments may increase chemical mobility and hence bioavailability of sediment-bound toxicants such as Cd. The objectives of this research were to study the chemical transformations of Cd in freshwater sediment as affected by pH and redox potential under controlled laboratory conditions and predict Cd behavior during dredging and disposal of Cd-contaminated sediments. Mississippi River sediment suspensions were incubated at four redox potential levels (-150, +50 +250, and +500 mV) at each of three pH levels (5.0, 6.5, and 8.0) and spiked with 0.2 ..mu..Ci carrier-free /sup 109/Cd/g solids. Sediment suspensions were sequentially extracted for easily mobile and potentially available /sup 109/Cd fractions. Essentially all of /sup 109/Cd extracted from alkaline sediment suspensions was associated with potentially available chelated, insoluble organic-bound and reducible fractions and was not affected by changes in oxidation-reduction conditions. A change from alkaline to acidic pH under moderately oxidized to well-oxidized conditions results in /sup 109/Cd transformations from potentially available organic forms to more mobile and readily available dissolved and exchangeable forms. This could create potential hazards of disposal of Cd-contaminated dredged sediments due to enhanced availability and leaching of Cd as affected by altered physiochemical environments.

• Research Organization: Louisiana State Univ., Baton Rouge
• OSTI ID: 5929179
• Journal Information: J. Environ. Qual.; (United States), Journal Name: J. Environ. Qual.; (United States) Vol. 10:4; ISSN JEVQA
• Country of Publication: United States
• Language: English

Related Subjects

520200* -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
BETA DECAY RADIOISOTOPES
CADMIUM
CADMIUM 109
CADMIUM ISOTOPES
CHEMICAL PROPERTIES
CHEMISTRY
DREDGING
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
ENVIRONMENTAL EFFECTS
EVEN-ODD NUCLEI
GEOCHEMISTRY
INTERMEDIATE MASS NUCLEI
ISOTOPES
METALS
MISSISSIPPI RIVER
NUCLEI
PH VALUE
PHYSICAL PROPERTIES
RADIOISOTOPES
REDOX POTENTIAL
RIVERS
SEDIMENTS
STREAMS
SURFACE WATERS
YEARS LIVING RADIOISOTOPES