10 million tonnes of plastic enter the ocean every year, mainly through rivers but as it turns out most plastic is not floating on the ocean surface.
Sea surface accumulations only account for 1% of the estimated marine plastic budget while microplastics account for 3.5 %. All the plastic that is seen in locations like the great pacific garbage patch is just the tip of the iceberg.
Just off the coast of Italy in the Mediterranean Sea the university of Manchester found a microplastic concentration of 1.9 million plastic pieces per square metre (190 pieces per 50 grams) on the ocean floor. Perhaps more disturbingly is that all seafloor samples that were taken contained microplastics.
The microplastics (fragments smaller than 1mm) are being concentrated in specific locations on the ocean floor by powerful currents, falling within a depth range of 600 to 900m, where the currents have the greatest interaction with the seafloor.
These ‘thermohaline-driven currents’, naturally build large accumulations of sediment on the seafloor but it has been shown that they also control the distribution of microplastics.
On the surface the currents concentrate plastics into giant floating garbage patches, below the surface they move and settle heaps of microplastics into biodiversity hot spots and owing to their small size, microplastics can be easily ingested by organisms of all sizes increasing transfer of harmful toxic substances throughout the food web and to us.
The average yearly human consumption of microplastic consumption ranges from 40,000 to 50,000 particles. The biggest known source of microplastics is bottled water, single-use water bottles contained up to 44 microplastics per litre and people who drink only bottled water ingest an additional 90,000.
We are consuming food along with its plastic packaging, but the research still is not conclusive about the amount of microplastics a body can tolerate or how much damage they do.
Another beverage drinks industry generating microplastics is the coffee industry, the disposable paper coffee cups, the ones lined with plastic. As the paper decomposes the thin plastic fragments into smaller and smaller pieced until they are microplastics and find their way into the ocean.
It is now the case that one kilogram of sea salt can contain over 600 microplastics.
Have a wonderful day.
HAQUA Research Dept.