MODELING THE BIOCONCENTRATION OF HYDROPHOBIC ORGANIC-CHEMICALS IN AQUATIC ORGANISMS

By incorporating organism growth into the bioconcentration process for hydrophobic organic chemicals (HOCs) in aquatic organisms, a set of e quations is proposed to express the time course for uptake of HOCs by the organism. The Boltzman equation, which produces sigmoidal curve an d is somewhat similar to the logistic growth equation, is used to desc ribe organism or population growth. The effect of metabolism can be in cluded, if desired. With the proposed model, values of uptake and elim ination rate constants, k(1) and k(2), and thereafter the bioconcentra tion factor, BCF, can be obtained, depending only on the time course f or uptake of HOCs by the organism. The set of equations is tested by u sing some published data for the time course of HOC uptake by aquatic organisms. The agreement of our values for k(1), k(2) and BCF with tho se in the literature is excellent. Various features of the proposed mo del are discussed. (C) 1996 Elsevier Science Ltd