The total amount of microplastics deposited on the bottom of oceans has tripled in the past two decades with a progression that corresponds to the type and volume of consumption of plastic products by society.
This is the main conclusion of a study developed by the Institute of Environmental Science and Technology of the Universitat Autònoma de Barcelona (ICTA-UAB) and the Department of the Built Environment of Aalborg University (AAU-BUILD), which provides the first high-resolution reconstruction of microplastic pollution from sediments obtained in the northwestern Mediterranean Sea.
Despite the seafloor being considered the final sink for microplastics floating on the sea surface, the historical evolution of this pollution source in the sediment compartment, and particularly the sequestration and burial rate of smaller microplastics on the ocean floor, is unknown.
This new study, published in the journal Environmental Science and Technology (ES&T), shows that microplastics are retained unaltered in marine sediments, and that the microplastic mass sequestered in the seafloor mimics the global plastic production from 1965 to 2016. "Specifically, the results show that, since 2000, the amount of plastic particles deposited on the seafloor has tripled and that, far from decreasing, the accumulation has not stopped growing mimicking the production and global use of these materials," explains ICTA-UAB researcher Laura Simon-Sánchez.
Read more at Universitat Autonoma de Barcelona
Image: Researcher Laura Simon-Sánchez during one of the sample collection campaigns (Credit: Lena Heins)