The ocean is slowly turning into a receptacle for a major portion of the trash generated by humans such as plastic bags, wood, metal and glass, which are washed into the ocean from a variety of sources. Every year around 280 million tons of plastic is produced worldwide, of which nearly 48 million tons are produced by the US alone. Every year, the ocean is trashed with 500 billion plastic bags and about 35 million bottles made out of plastic. Such a trend is now being recognized as an environmental threat to not just the organisms living in and around the ocean but also humans since the plastic debris tends to produce harmful persistent, bio-accumulating and toxic substances (PBTs). This trend also affects the tourism since the ambience of the seashore is lost under the heaps of garbage littered around the beaches. Terms such as “garbage patch” or “convergence zone” are becoming increasingly relevant due to the tendency of the ocean waves to carry the buoyant plastics to five main gyres in the world. The five gyres where most of the world’s plastic accumulates are the Indian Ocean, North and South Pacific Ocean and the North and South Atlantic Ocean. Simulation models of 10 years of trash floating shows that the West coast of North America and the West and East coasts of South America are highly vulnerable.

Plastic are not biodegradable. An example of this durability was explained by the 28,000 plastic ducks lost in the Pacific Ocean more than 20 years ago, somewhere between Hong Kong and the USA. Experts believe that 2000 plastic ducks from that cargo are still floating in the Pacific Garbage Patch, often washing ashore in intact conditions in Hawaii, Australia, South America and Alaska. Some of the plastics can be degraded by UV rays, although it is extremely slow and remain on the ocean bed for possibly hundreds of years. Ingestion of smaller plastic, metal or glass trash could slowly kill sea organism. Microplastics that contain plasticizers such as bisphenol A (BPA) affect hatching success in many sea organisms and cause developmental abnormality. Humans could be affected if they ingest such a contaminated sea creature.

The Global Programme of Action (GPA) for the Protection of the Marine Environment from Land based Activities is an initiative that provides guidelines to tackle invasion of plastic and marine debris.

S. Park