Marine debris is any man-made solid material entering waterways (oceans) directly or indirectly. Marine debris can be simple items like soda cans, fish hooks, plastic commodities, etc. almost 80% of marine debris is generated from land sources like municipal landfills, discharge of untreated sewage and stormwater, industrial facilities, and tourism. All these potentially end up in oceans and pose threat to marine life. The main reason for all this debris entering water bodies is improper waste management.
The marine debris (mostly plastics) reaches the deeper parts of the ocean, as recently scientists working in marine found microplastics in 100% of the crustaceans they examined that came from deeper and darker parts of the oceans. The plastic crisis is so high that 97% of all fish species have microplastics in them. An average person eats 1000 bits of plastic every year and the main source is through the water. More than 5.6 million tonnes of marine debris every year is estimated to come from ocean-based sources like merchant ships, ferries, and cruise liners. Of all the plastic dumped into the sea annually, 15% floats on the surface, 15% is washed to the shores and the remaining 70% will sink to the sea bottom.
Fishes and other sea creatures consume plastic directly or indirectly (by consuming other sea creatures) and that’s how it enters the cycle of life along with many toxic pollutants, ingestion of the debris ultimately kills the birds, fishes, mammals. Sea turtles mistake floating plastic for jellyfish. Entanglement of fishnets/lines can hamper marine mobility, it causes various other problems of breathing, trouble in eating once entangled. Marine debris causes damage to shipping vessels through collision, entanglement in propeller blades, and clogging of water intakes for engine cooling systems. Plastic debris acts as a sponge for toxic, hormone-disrupting chemicals like Polychlorinated Biphenyl (PCBs) and Dichloro-Diphenyl-Trichloroethane (DDT) that reside in seawater.
The marine debris mostly plastics (in the form of microplastics) contributes to the melting of polar ice glaciers which leads to the rise in sea level raising more problems.
We now know that what we careless dump in oceans is not only affecting us but also other organisms, and the worst part is not many realize it even today and continue to contribute to this harmful debris. Our irresponsible and insensitive behaviour has caused an ecological imbalance. We can only contribute by completely banning the dumping activity in water bodies and taking the responsibility of removing debris from the same when it comes to our notice.