Microplastic in the Oceans
A study led by the UK’s National Oceanography Center analyzed the upper layers of water -up to 200 meters deep- in the middle of the Atlantic Ocean. During this research mission from the United Kingdom to the Falkland Islands, scientists detected up to 7,000 microscopic plastic particles per cubic meter of seawater. Based on this analysis, it is estimated that there are 12-21 million tons of microplastic particles in the waters of the Atlantic Ocean. This amount of microplastic is estimated to be enough to fully fill almost 1000 cargo ships.
The most common sources of microplastic is plastic that is often used in packaging and ends up as waste in the oceans, i.e. polyethylene, polypropylene, and polystyrene. Another lesser known source is paints on metal surfaces. It is estimated that about 1.5-2.25 million tons of microplastic coming from paints on metal surfaces enter the oceans, a quantity equivalent to 150-225 billion empty plastic bottles. If one considers that the amount of plastic that ends up in the oceans every year is estimated to be around 8 million tons, then it becomes clear that paints on metal surfaces contribute a significant percentage of the total amount. This kind of microplastic particles appear to be produced by the corrosion, tear, and general wear of painted metal surfaces, but also by the traditional open-blasting methods used during cleaning and maintenance of metal surfaces.
Finally, it is worth noting that a recent scientific publication investigated the possible function of marine microplastic particles as carriers of pathogenic microorganisms and as vectors of diseases, and concluded by recommending further research on this critical issue.