A study by the Federal University of São Paulo (Unifesp) reveals high levels of microplastic contamination in the Santos estuary on the São Paulo coast.
The study focused on the ferryboat area, Góes Beach, and Palmas Island.
Comparing data from 100 studies conducted in 40 countries, researchers found the ferryboat area to be the most contaminated, with oysters and mussels showing poor health conditions and 12-16 plastic particles per gram of tissue.
One mussel contained over 300 microplastics per gram, raising concerns for the approximately 300 residents of Góes Beach who likely consume these contaminated shellfish.
The study, published in the journal Science of the Total Environment, highlights oysters and mussels as indicators of contamination, using two species, Crassostrea brasiliana and Perna perna, to establish this conclusion.
The research team plans to analyze stored samples from zoological collections to understand the historical timeline of shellfish contamination in the region.
Microplastic contamination in the Santos estuary is primarily caused by domestic sewage discharge containing laundry waste, including colorless fibers, cellulose, and acrylic compounds. Textile fibers were the most prevalent microplastic type.
The study emphasizes the need for new public policies on basic sanitation in Brazil, as current legislation lacks requirements for microplastic removal from effluents.
This poses risks to the estuary’s health, organisms, and human well-being.
Plastic pellets from shipping operations are a concern, but they were not the source of microplastics found in the mollusks.