Anthropogenic pollution in marine ecosystems presents a multifaceted threat, with both physical and chemical contaminants posing potential risks to marine life and human consumers. This study investigates the occurrence of microplastics (MPs) and chlorinated paraffins (CPs) in chondrichthyan and teleost fish species from coastal waters of Argentina. Fish specimens were collected from the Buenos Aires province coastline, specifically from Balneario Claromecó and the Bahía Blanca Estuary. Digestive tracts were analyzed for MPs using KOH digestion and microscopic identification, while sharks muscle tissue was assessed for short- and medium-chain CPs (SCCPs/MCCPs) via gas chromatography. Results revealed a high incidence of MPs, with an average of 19.5±11.1 items ind.-1 in the endangered angel shark (Squatina guggenheim) and 8.9±4.3 items ind.-1 in the elephant fish (Callorhinchus callorhynchus), predominantly as transparent fibers <1000 µm. Polymeric composition included chlorinated polyethylene, polyester, and textile blends. In the prey fishes while the abundance of MPs was in a similar range, CPs were detected in 41% (SCCPs) and 36% (MCCPs) of the analysed fish, with amounts ranging up to 29 ng g−1 and 19 ng g−1 wet weight, respectively. Homolog profiles were dominated by C10-11Cl6 for SCCPs and C14Cl6-7 for MCCPs. A preliminary human health risk assessment for CPs indicated no immediate risk from fish consumption based on current guidelines; however, the combined presence of MPs—which can act as vectors for chemical additives like CPs—highlights a complex exposure pathway. These findings provide the first evidence of CPs in the South Atlantic Ocean and, when integrated with MP data, underscore the need for holistic monitoring strategies that assess both particle and chemical pollution to fully understand the ecological and public health implications of contaminated seafood.

Microplastics,Chlorinated Paraffins,Chondrichthyes,Seafood Safety,Risk Assessment