THE INTERACTION OF CARBON-14 HEXACHLOROBIPHENYL (CARBON-14-PCB) WITH PHYTOPLANKTON UNDER VARIOUS ENVIRONMENTAL CONDITIONS (ALGAE, PARTITION COEFFICENT, BIOACCUMULATION)
Abstract
A recently developed radio-bioassay was adapted and modified to measure the sorption of ('14)C-hexachlorobiphenyl (('14)C-PCB) onto freshwater algae (Chlorella pyrenoidosa, Scenedesmus quadricauda) and marine (Nannochloris atomus, Skeletonema costatum) phytoplankton. Freundlich sorption isotherms, generated by the bioassay, satisfied the assumptions of the equilibrium partitioning model for toxicant accumulation in the biosphere. These formulations of the BET isotherm produced partition coefficients--a measure of sorptive capacity. ('14)C-PCB exists in the aqueous phase as an emulsion. The magnitude of partitioning of the toxicant from the aqueous phase onto the particulate (algal) phase was a function of that toxicant's environmental concentration of the organic content of the cells, and of environmental parameters (salinity and temperature). Partition coefficients increased with increasing phytoplankton biomass and surface to volume ratios. Higher experimental salinity levels led to larger ('14)C-PCB aggregates in the emulsion and corresponded to a salinity--dependent reduction of sorptive capacity. As predicted from Gibb's free energy considerations, high incubation temperatures resulted in lower partition coefficients. The agreement of these results with classical multilayered sorption theory indicates that this research has achieved a more realistic representation, than that offered by previous investigators, of the interaction of ('14)C-PCB with particulates in the freshwater/marine environment. The implications of this behavior in aqueous phase demonstrate the efficacy of the bioassay as a physiological and biochemical tool for validation and calibration of the equilibrium partitioning model.
Subject Area
Ecology
Recommended Citation
ROSCIGNO, PASQUALE FRANK, "THE INTERACTION OF CARBON-14 HEXACHLOROBIPHENYL (CARBON-14-PCB) WITH PHYTOPLANKTON UNDER VARIOUS ENVIRONMENTAL CONDITIONS (ALGAE, PARTITION COEFFICENT, BIOACCUMULATION)" (1984). ETD Collection for Fordham University. AAI8506358.
https://research.library.fordham.edu/dissertations/AAI8506358
