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Updated: May 11, 2026
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A Fish-feeding Laboratory Bioassay to Assess the Antipredatory Activity of Secondary Metabolites from the Tissues of Marine Organisms
Published on: January 11, 2015
Assessing bioavailability of DDT and metabolites in marine sediments using solid-phase microextraction with
Lian-Jun Bao1, Fang Jia, J Crago
1Department of Environmental Science, University of California, Riverside, CA, USA. lyla.bao@ucr.edu
Environmental Toxicology and Chemistry
|May 11, 2013
Summary
This study introduces a faster method using stable isotope-labeled analogues as performance reference compounds (PRCs) with solid-phase microextraction (SPME) to measure contaminant concentrations in sediments. The PRC-SPME approach significantly reduces sampling time while maintaining accuracy for hydrophobic compounds like DDT.
Area of Science:
- Environmental Chemistry
- Analytical Chemistry
- Environmental Science
Background:
- Solid-phase microextraction (SPME) is widely used for estimating freely dissolved contaminant concentrations (Cfree) in sediments.
- A major limitation of SPME is the long equilibrium time required, especially for hydrophobic compounds like DDT.
- Accurate measurement of Cfree is crucial for assessing contaminant bioavailability and ecological risk.
Purpose of the Study:
- To develop and validate a novel SPME method using stable isotope-labeled analogues as performance reference compounds (PRCs) to accelerate Cfree measurements.
- To assess the accuracy and efficiency of the PRC-SPME method for determining DDT and its metabolites (DDTs) in marine sediments.
- To evaluate the correlation between PRC-SPME derived Cfree values and actual bioaccumulation in benthic organisms.
Main Methods:
- Stable isotope-labeled analogues (deuterated or C-13 labeled) were impregnated into polydimethylsiloxane (PDMS) SPME fibers as PRCs.
- The PRC-SPME method was applied to historically contaminated marine sediment, comparing results with conventional equilibrium SPME (Eq-SPME).
- Bioaccumulation of DDTs in the marine worm Neanthes arenaceodentata was assessed and correlated with fiber equilibrium concentrations.
Main Results:
- The PRC-SPME method achieved Cfree values for DDTs identical to Eq-SPME but reduced the required mixing time from 9 days to 9 hours.
- Desorption and absorption kinetics of PRCs and DDTs were found to be isotropic across various sediments.
- Strong correlations were observed between PRC-SPME derived equilibrium concentrations and lipid-normalized tissue residues in exposed worms.
Conclusions:
- Coupling PRCs with SPME sampling offers a significant reduction in analysis time for Cfree measurements of hydrophobic contaminants.
- The PRC-SPME method provides a more flexible and efficient tool for evaluating contaminant bioavailability in environmental matrices.
- This approach enhances the practical application of SPME in environmental monitoring and risk assessment studies.
