PARENT SESSION
PW13 - Trophic Transfer
Wednesday, 20 November 2002
8:00 AM to 6:30 PM
Exhibit Hall

(P876) PAHs in the Lake Michigan Aquatic Ecosystem.

Fernandez, Joseph^*,1, Burkhard, Lawrence¹, Cook, Philip¹, Nichols, John¹, ¹ Mid-Continent Ecology Division, U.S. EPA, Duluth, MN, USA

ABSTRACT- In this study, we are investigating the accumulation of PAHs in the Lake Michigan food web. Focusing on EPA's 16 "Priority Pollutant" PAHs and the methyl- and dimethyl-analogs of several of these PAHs, chemical analyses were performed on archived samples of water, sediment, invertebrates (Mysis spp.and Diporeia spp.) and fish species representing different trophic levels (alewives, chubs, sculpins, smelt and multple age classes of lake trout) which were collected in conjunction with U.S.EPA's Lake Michigan Mass Balance Study (LMMBS). Because PAHs are metabolized by aquatic species and some of the subject fish species have high lipid contents, e.g., >20%, sample preparation techniques were optimized for low detection levels using GC/MS in tissues with high lipid content. These data will be used to calculate bioaccumulation factors (BAFs) and biota sediment accumulation factors (BSAFs). The BAFs and BSAFs will be compared to values determined from mechanistic models and a suite of compounds with differing metabolism rates ranging from recalcitrant PCBs to the more metabolizable PAHs. These data will augment efforts to reduce large uncertainties in risk assessments and water quality criteria developed for PAHs. This abstract does not necessarily reflect EPA policy.

Key words: PAH, BAF, BSAF, Lake Michigan