Plastic the Evil in blue water
The world’s biodiversity is under a vast threat nowadays due to development, human population growth, and industrialization. Human activities are the leading cause of loss of biodiversity worldwide. Species extinction rates have gone beyond the natural rate to 1000-10,000 times, mainly due to human activities (Lovejoy, 1997). The marine environment also experiences the threats of human activities in various ways. Dumping waste into the marine environment is the most significant damage, humans created it. Apart from that, over-fishing, over-exploitation, alien species, and dredging harms the marine environment. Above all, plastic pollution is the most significant danger to the marine environment. Oceans and coastal areas have become highly polluted with plastic debris, which releases to the environment after human and industrial consumption.
Worldwide annual plastic production is about 330 million metric tons, with a yearly production rate of 6% (Europe, 2016). Large volumes of plastic become debris from packaging applications and disposable products.
Any solid material that enters the ocean, which is persistent, manufactured, or processed, is considered as marine litter (Coe and Rogers, 1997). Apart from the above human-mediated process, natural scenarios like a tsunami, floods, and cyclones govern ocean pollution.
Million years before, humankind intentionally released plastic debris into oceans assuming that oceans are capable of self-cleansing. It would be correct unless the human population growth rate and industrialization were not growing exponentially. Million years ago, coastal pollution was very low, human needs were lower, and considerable pollution did not exist. The question of marine pollution was first discussed in 1970 through academic publications, and it was identified as an environmental problem (Markic, 2014). Those studies found plastic debris from the ocean surface, on the seabed, and as costal accumulations (Feder, Jewett, and Hilsinger, 1978). However, all the studies revealed that the leading cause of marine pollution is the mismanagement of solid plastic waste.
Most of the anthropogenic plastic debris enters the ocean due to improper waste management practices, and some enter through various human activities such as street and beach littering fishing and shipping activities and natural disasters. Sources of marine pollutants can be classified mainly under two categories as 1) land-based and 2) ocean-based (Markic, 2014).
Debris that comes from land originates from densely populated coastal areas. Coastal regions closely related to the high industrial areas, or else metropolitan regions tend to produce more plastic debris compared to less industrialized areas. The wind and rain can transport producing plastic litter to the ocean.
Emissions from untreated municipal waste, storm-water release and industrial waste
From ancient times, we can see human settlements were forming near to water sources such as rivers or lakes. From that era with the development of human civilization, they have been using drainage systems to dispose of waste matters. At present, means of mass-scale industrial waste disposal and as the storm-water release can find with this practice.
Plastic from ocean-based activities
The most crucial ocean-based activities that create possible pollution risk to the ocean can consider as shipping and fishing. Merchant shipping tends to produce the highest marine debris pollution compared to other shipping purposes. Commercial fishing releases waste associated with cargo and operational activities. They include plastic pallets, wires, and other crew related plastics.
The polymerization reaction of monomers obtained from crude oil and gas produce plastics. Usually, adding stabilizers improve the pure(virgin) plastic to improve its performance. Plastic materials are highly diverse, and the most common type of plastic is Polypropylene (PP) and Polythene (PE). Polyvinyl chloride (PVC), Polystyrene (PS) are some of the other types. Once a plastic component gets entered into the environment, it undergoes deterioration due to environmental factors (Andrady, 2003, p 313).
Generally, microplastics are small plastic fragments with a diameter of less than 5mm (Barnes et al., 2009).Two groups can categorize microplastic as primary and secondary. Breaking down larger plastics formed primary microplastics are the little ones and secondary ones.
Distribution of Plastic in the ocean environment
It is difficult to get an exact measurement for marine plastics because it spreads all over the oceans globally, and marine pollution with plastic is not point sourced. Only 30% of marine plastic ended up in the coasts, and the remaining 70% reach the seabed have made with it.As responsible pathways to circulate plastic debris across the world’s oceans, have identified ocean currents (surface currents and deep-ocean currents).Motions in the oceans are continuous due to the earth’s rotation and the sun’s energy. Wind-driven ocean currents and density-driven deep ocean currents carry plastic and other debris across oceans.
Effects of Micro-plastic Pollution.
The number of incidents recorded on the impacts of marine plastic debris pollution on aquatic life has increased over time. Plastic ingestion and Entanglement are the two significant consequences that occur due to plastics.
Micro and macro plastic ingestion by sea birds
This is one of the most reported incidents related to aquatic animals over the past years. Plastic pallets were initially found from the gut dissections of beached prions Pachyptila Salvini and Pachyptila desolata from New Zealand beaches (Harper and Fowler, 1987). Plastic pallets were also found from Leach’s Petrels (Oceanodroma leucorhoa) from Newfoundland (Rothstein, 1973), gulls, and turns from Great Gull Island, New York (Hays and Cormons, 1974), etc. Hays and Cormons (1974) hinted that the ingestion of plastic pallets by sea birds could happen either via primary ingestion (directly eating) or via secondary ingestion (by having small fish who has eaten plastic pallets). In 2011, Carey found that parental feeding can also ingest plastic to juvenile sea birds when parent birds feed the food mixed with plastic pallets.
Entanglement; sea turtles
Plastic debris in the oceans gets entangle to marine animals, especially turtles, sea birds, and fish causing harmful effects for them. The effects include strangulation, drowning, infection, or tissue damage. When fishing nets, ropes releases to the ocean as trash, they can get entangled in turtles and fish fins, so those animals fail to swim properly or do any vital activity well. It is sometimes lethal for them.
Impacts on Human
Marine plastic pollution can get impact to humans in many ways. Health and economic impacts are primary among them. Health impacts humans due to pathogenic bacteria or viruses or ingestion with seafood due to physical injuries or infections. Sharp plastic objects in the beaches can get harm to people.The suspend plastic particles in water can get harm swimmers or divers.
Management actions to prevent pollution
To assess the level of pollution, responsible authorities should carry continuous research and monitoring activities. Environmental monitoring is a critical aspect of conserving the marine environment. Adequately managed and activated should with legislation. We should appropriately maintain waste and storm-water management plans. By initiating plastic recycling practices, it can reduce plastic waste generation and release it into the environment.