TA8 Assessing Toxicity: Critical Body Residue Approach
Room 19A/B, Level 4
8:00 AM - 12:00 PM, Tuesday, 11 November 2003
Chair: Meador, James , Lotufo, Guilherme ,
(237) Linking critical body residues with equilibrium sampling devices for ecological risk assessment.
Lanno, R.1, Voigt, A,1, Tost, B.1, Wells, J.2, TenEyck, M.3, 1 Ohio State University, Columbus, OH2 USGS, Columbia, MO3 University of Wisconsin-Superior, Superior, WI
ABSTRACT- Physical and chemical characteristics of soil such as organic carbon and particle size distribution modify the bioavailability of polycyclic aromatic hydrocarbons (PAHs) to soil-dwelling invertebrates. Variation in these same soil characteristics results in a poor correlation between total PAH measures of exposure and observed organism effects. Critical body residues offer one alternative for expressing exposure relatively independently of physical and chemical soil characteristics. However, in some soils, matrix effects are observed in soil test organisms. In such systems, a biomimetic equilibrium sampling device may be a useful tool for determining chemical exposure. Biomimetic sampling devices, such as solid-phase microextraction (SPME) fibres, provide an indirect measure of chemical bioavailability that may correlate well with bioaccumulation and/or toxicity in soil invertebrates. Phenanthrene (PHE) accumulation by the earthworm (Eisenia fetida) was well correlated with PHE determinations in soil using SPMEs (r=0.93), but not with total PHE levels. The relationship between tissue chemical residues and chemical availability as determined using equilibrium sampling devices will be discussed in the context of ecological risk assessment.
Key words: bioavailability, critical body residues, earthworms, PAHs