Bioaccumulation of super‐lipophilic chemicals in fish

Abstract
The influence of increasing molecular size and hydrophobicity on bioaccumulation kinetics in guppies (Poecilia reticulata) was investigated for a series of polychlorinated biphenyls (PCBs) in comparison with other halogenated aromatic compounds. Extremely low clearance rates were characteristic of the higher chlorinated biphenyls and resulted in a linear accumulation in fish. For these compounds, in contrast to more soluble chemicals, direct uptake from water appeared to be less efficient than uptake from contaminated food. Hexabromobenzene, octachlorodibenzo‐p‐dioxin and tetradecachloroterphenyl were not accumulated by living fish. The importance of food‐chain accumulation (biomagnification) versus direct bio‐concentration is discussed in relation to molecular structure and physico‐chemical properties of organic chemicals.