The primary focus of research in our laboratory lies in applied and theoretical aspects of determining the bioavailability of chemicals in the environment, particularly in soil systems. We strive to understand and interpret bioavailability as it relates to 1) soil-chemical interactions; 2) interaction, uptake, and distribution within organisms; 3) toxicity and bioaccumulation at the organism, population, and community level; 4) development of models to describe relationships between chemicals, environmental matrices, bioaccumulation, and toxicity; 5) in vivo and in vitro techniques for measuring dietary bioavailability; 6) development of environmental quality guidelines and cleanup policy; 7) ecological risk assessment. Specifically, research examines the relationship between the uptake, kinetics, and body residues of chemicals and toxicity endpoints such as lethality, growth, reproduction, or biomarkers in both aquatic and terrestrial systems. Organisms that have been used as models in examining bioavailability include earthworms, soil arthropods (Collembola, isopods), and fish.
Complementing research on chemical bioavailability, we also examine the development and application of biomimetic sampling devices as organism surrogates that can be used to measure the potentially bioavailable fraction of chemical in environmental matrices. Examples include solid-phase microextraction (SPME) fibres semi-permeable membrane devices (SPMDs) for organic chemicals and cation/anion exchange resins for metals.
Another area of research is the development and application of methods for the use of community structure and terrestrial model ecosystems (TMEs) in assessing the effects of chemicals in soil systems.