For the first time, researchers have quantified the amount of plastic waste entering the ocean from land. In 2010, an estimated eight million tonnes of plastic waste made its way into the ocean; it is nearly the amount of plastic generated globally in 1961. The results of the study were published in the journal Science on February 13, 2015.
Most of the plastic waste that enters the ocean is on account of plastic litter and mismanaged plastic waste systems in several countries. The total amount that ended up in the ocean would have been much higher as the study did not take into account the contribution from other sources like fishing activities or at-sea vessels.
Twenty countries accounted for 83 per cent of mismanaged plastic waste that entered the ocean. The list of countries that pumped the greatest amount of waste into the ocean was arrived at by taking into account the population and quality of waste management systems in place.
India, with 0.60 million tonnes per year of mismanaged plastic waste, is ranked 12th. China ranks no. 1 with 8.82 million tonnes per year of mismanaged plastic waste. There are 11 Asian and Southeast Asian countries in the list, including Sri Lanka, Bangladesh, Pakistan and Burma.
The cumulative amount of plastic debris that would enter the ocean in the next decade will be more than double the 2010 figure in the absence of any improvement to waste management systems in the 192 coastal countries. In 2010, 275 million tonnes of plastic waste was generated in the world’s 192 coastal countries. It is very unlikely that a global “peak waste” will be reached before 2100.
With a 50-per-cent improvement in waste disposal in the 20 top-ranked countries, the mass of mismanaged waste will fall by 41 per cent by 2025.
Alternatively, a 26-per-cent decrease in waste can be achieved by 2025 if per capita waste generation is reduced to the 2010 average (1.7 kg per day) in the 91 countries that exceed it.