|
(39-03) Factors affecting bioaccumulation of PCDD/Fs and PCDEs. Lyytikäinen, Merja*,1, Rantalainen, Anna-Lea2, Mikkelsson, Pirjo3, Hämäläinen, Heikki4, Paasivirta, Jaakko3, Kukkonen, Jussi1, 1 University of Joensuu, Joensuu, Finland2 University of Helsinki, Lahti, Finland3 University of Jyväskylä, Jyväskylä, Finland4 Karelian Institute, Joensuu, Finland ABSTRACT- Bioaccumulation patterns of sediment-associated dibenzo-p-dioxins, furans (PCDD/F) and −ethers (PCDE) in Lumbriculus variegatus tissue and semipermeable membrane devices (SPMD) were studied. The biota-sediment accumulation factors (BSAFs) for individual congeners were determined after a 28-d laboratory exposure with contaminated river sediments. Several hexa-, hepta- and octachlorinated congeners were found to bioaccumulate, which aroused particular interest since octanol-water partition coefficient (Kow) and molecular weight (MW) of these compounds are high (logKow > 7, MW > 350). Potential relationships between the observed BSAFs and physico-chemical characteristics of the congeners were analyzed in order to get some insight into factors possibly controlling the bioaccumulation. Decreasing water solubility explained best the observed decline in bioaccumulation factor among congeners for L. variegatus. For SPMD, both decreasing water solubility and increasing molecular weight were associated with the decline. The planarity of the molecule appeared to affect the bioaccumulation potential also. The physico-chemical characteristics studied here associated best with the behavior of coplanar PCDD/Fs. Key words: PCDD/F, PCDE, physico-chemical characteristics, bioaccumulation |
