Beached microplastics at the Bahia Blanca Estuary (Argentina): Plastic pellets as potential vectors of environmental pollution by POPs

Microplastics (MPs) from the coastal areas of a highly anthropised estuary were sampled to assess their distri-bution in coastal sediments and their role as potential vectors of pollution. The average MP density was 1693 +/- 2315 MPs/kg, which mainly accumulated in the high tide and storm berm areas of the beach. The Microplastic Pollution Index (MPPI), Microplastic Impact Coefficient (CMPI), Hierarchical Cluster Analysis and Principal Component Analysis revealed spatial variation in MPs pollution. High-density polyethylene plastic pellets were abundant at two beaches (192 +/- 218 MPs/kg sediment). Furthermore, the presence of sorbed chemicals on pellets was assessed through GC-MS, showing 0.95 +/- 0.09 ng/g of E7OCPs, 4.03 +/- 0.89 ng/g of E7PCBs, 108.76 +/- 12.88 ng/g of E16 PAHs and 122.79 +/- 11.13 g/g of E29 PAHs. The sorption capacity of plastics, combined with their abundance, poses an environmental concern and also highlights their suitability as in-dicators of chemical exposure.

Automated summary

Microplastics (MPs) were sampled from a highly anthropised estuary's coastal areas to assess their distribution in coastal sediments and their potential role as pollution vectors. The average MP density was 1693 +/- 2315 MPs/kg, with accumulation mainly in high tide and storm berm areas of the beach. Various analysis techniques revealed spatial variation in MPs pollution and the presence of sorbed chemicals on plastic pellets. This highlights the environmental concerns and their significance as indicators of chemical exposure.