Bioaccumulation of PCBs and OCPs in Antarctic phytoplankton and zooplankton: Insights into bioconcentration and biomagnification in Fildes Bay.

This study was conducted at Fildes Bay, King George Island, Antarctica, from November 30th, 2019, to January 30th, 2020. We determined the concentrations of Organochlorine Pesticides (OCPs) and Polychlorinated Biphenyls (PCBs) in phytoplankton, and zooplankton. The most abundant compounds found were hexachlorobenzene (HCB) in phytoplankton and γ-HCH in zooplankton. We estimated the bioconcentration factors (BCF) for phytoplankton and zooplankton (BCF), as well as biomagnification factors (BMF) across trophic levels. Our findings indicate that BCF values were generally higher for compounds with a higher degree of chlorination, and noticeable biomagnification of these contaminants was observed, emphasizing the enhancement of contaminant concentrations from phytoplankton to zooplankton. This biomagnification varied depending on the specific compound and environmental conditions. Throughout the study period, the factors influencing bioconcentration and biomagnification were closely correlated with the seasonal dynamics of the phytoplankton biomass, which were affected by local conditions such as slower S and SE winds. These events enhanced the concentration of chlorophyll-a and POPs, influencing their transfer across trophic levels. Our study underscores the complex interplay between biotic and abiotic factors in determining the fate of these persistent pollutants in a rapidly changing polar environment. These findings highlight the need for continuing ongoing monitoring to understand the long-term impacts of environmental changes on the distribution and behavior of hazardous substances in remote regions like Antarctica.