Resin pellets from beaches of the Portuguese coast and adsorbed persistent organic pollutants

Abstract

The occurrence of stranded plastic marine debris along the Portuguese coastline was investigated. Number of items m−2 and size range of resin pellets were recorded, corresponding to 53% of total marine debris collected items. In addition, concentrations of adsorbed persistent bioaccumulative and toxic chemicals (PBTC) were determined, PAH – polycyclic aromatic hydrocarbons; PCB – polychlorinated biphenyls and DDT – dichlorodiphenyltrichloroethane. Matosinhos (Mt) and Vieira de Leiria (VL) presented the highest number of items m−2 (362 and 332, respectively). Resin pellets with 4 mm diameter were the most abundant (50%). Contaminants concentration was variable. PAH concentrations recorded values between 53 and 44800 ng g−1, PCB ranged from 2 to 223 ng g−1 and DDT between 0.42 and 41 ng g−1. In general, aged and black pellets recorded higher concentrations for all contaminants. Matosinhos (Mt), Vieira de Leiria (VL) and Sines (Si), near industrial areas and port facilities, were the most contaminated beaches. Research efforts are needed to assess the points of entry of industrial plastic pellets in order to take action and minimize impacts on the ecosystems, in particular, points of transfer during transportation from plastic manufacturers to plastic converters should be identified and controlled so that virgin pellets are contained and will not enter rivers and be carried to the oceans where they can remain for a long time and travel great distances.