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Updated: Jun 1, 2026
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Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies
Published on: July 1, 2016
Geochemical controls on trace element mobilization in contaminated estuarine sediments
Guanlei Li1, Xiao Jian2, Zhilang Lao1
1Archaeology, Environmental Changes & Geo-chemistry (AMGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, Brussels 1050, Belgium.
Journal of Hazardous Materials
|May 30, 2026
Summary
Early diagenesis in Scheldt sediments releases trace elements like Fe and Mn under specific conditions. High sediment concentrations pose a potential ecological threat due to possible future release.
Area of Science:
- Environmental Chemistry
- Geochemistry
- Sedimentology
Background:
- Early diagenesis significantly influences metal behavior in estuarine sediments.
- Understanding trace element dynamics is crucial for assessing ecosystem health.
Purpose of the Study:
- Investigate the impact of early diagenesis on trace element behavior (Fe, Mn, Cr, Co, Pb, As, Cu, Cd, Ni, Zn, P) in Scheldt sediments.
- Compare current conditions with historical data from the early 1990s.
Main Methods:
- Diffusive Gradient in Thin-films (DGT) sampling for labile metal fractions.
- Visual MINTEQ modeling for speciation and saturation index calculations.
- Principal Component Analysis (PCA) for element behavior analysis.
Main Results:
- Trace element mobilization linked to iron/manganese oxyhydroxide dissolution under sub-oxic conditions and lower pH.
- Labile element fractions varied with sediment depth and season.
- Oversaturation of specific minerals (CoFe2O4, Hematite, MnHPO4(s), Rhodochrosite) observed.
- Compared to the 1990s, lower dissolved Fe/Mn but higher porewater trace elements were found in 2023, despite similar solid-phase concentrations.
Conclusions:
- Estuarine sediment solid phases act as significant reservoirs for trace elements.
- These reservoirs pose a potential threat due to release under specific physico-chemical conditions.
- Diagenetic processes and historical pollution impact current trace element behavior and bioavailability.
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