Costa, M.F. ; Silva-Cavalcanti, J.S. ; Barbosa, C.C. ; J.L. Portugal and Barletta, M.
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ABSTRACT Plastics have become the most important marine contaminant of the XXI Century. Benthic fauna is not frequently a concern, but can ingest plastics which suffered fragmentation and chemical contamination accumulated in the sediments. This work approaches the amounts and types of plastic buried in the sediments of an intertidal plain on the Northeast coast of Brazil. During one seasonal cycle, 450 samples of sediment were taken. Sediments were sieved (1mm mesh). Thirty-eight plastic fragments of different sizes and types occurred distributed in space and time. Plastics size varied from 1mm to 160cm2. All plastics were heavily weatherized. Soft plastics, nylon and hard plastics items were found. The most likely sources of these plastics are the river basin, the communities that inhabit the margins of the estuary, fishery activities and the mangrove forest. A significant difference between the rainy and dry seasons was detected for the amount and type of plastic found (plastic or nylon) among three sampling areas. Nearer to the mangrove forest there was a larger accumulation of plastic items. This estuary is undergoing an intense process of aggradation and there is a possibility of dredging of the main channel and harbor areas. This, plus the disposal of spoils will further spread the plastics once buried. The dredged areas will become a secondary source of plastics as their pollution burden will be, once more, exposed to tidal currents and main channel flow. |