First basin-scale assessment of PCB and DDT contamination in Mediterranean zooplankton: a baseline for the central–southern basin

Abstract

dw), primarily as degradation products (DDE and DDD), indicating legacy inputs. Spatial patterns revealed higher PCB levels in coastal areas affected by industrial and urban pressures (e.g. Athens and eastern Sicily), while DDTs were more associated with regions influenced by historical agricultural use and riverine inputs (e.g., western Greece). Offshore sites showed low contamination levels, highlighting the influence of land-based sources. Comparative analyses revealed significantly lower PCB and DDT concentrations than those reported for the Tyrrhenian Sea (ANOVA, p < 0.0001; Kruskal-Wallis, p = 0.0116), supporting a longitudinal contamination gradient across the Mediterranean basin. This study provides a baseline for the central-southern Mediterranean and confirms zooplankton as an effective POP bioindicator. Future studies should extend monitoring and integrate chemical and eDNA approaches to improve basin-scale assessments of Mediterranean marine ecosystems.