Aquaculture in the crossroad of microplastic contamination

Plastic pollution threatens life and human health, with microplastics (MP) linked to seafood consumption. MPs enter aquaculture through the environment and from aquaculture gear. During aquaculture production, plastic is used in nets and sacks for the growth process and in collecting and processing so it becomes important to expand the knowledge about how much MPs are present in seafood. The aim was to investigate the presence of MPs in three bivalve's species; oysters (Crassostrea gigas), clams (Ruditapes decussatus), and mussels (Mytilus galloprovincialis) produced in offshore and intertidal aquaculture in two different climate conditions. Water, bivalves and sediments were collected from each site and abundance, size, colour, type and composition of the MPs polymers analysed. The most common colour in offshore aquaculture was blue while in intertidal was black, and the type was fragments. Sixty per cent of bivalves did not have MPs in their tissues. Bivalves from offshore aquaculture was less impacted by MPs probably due to the hydrographic conditions and distance from the coast. Most of MPs ingested by bivalves were related to the plastic type used in aquaculture materials. Transformative solutions and/or procedures to eliminate plastic from aquaculture equipment are needed, and depuration might be a practical solution.