Marine Plastic Pollution in Waters around Australia: Characteristics, Concentrations, and PathwaysPosted on October 30, 2015 by DrRossH in Plastic Waste News
Plastics are a diverse group of materials derived from petrochemicals . Their global production has grown exponentially from 1,700,000 tonnes in 1950 to 280,000,000 tonnes in 2011 . The disposability of plastics, together with their low recycling rates, has contributed to a significant rise in the amount of waste produced globally . For instance, in Australia, 1,433,046 tonnes of plastics were used in 2010–2011, of which only 20% was recycled. Moreover, around 37% of this plastic was for the manufacturing of single-use disposable packaging . Plastics are transported from populated areas to the marine environment by rivers, wind, tides, rainwater, storm drains, sewage disposal, and even flood events. It can also reach the sea from vessels (e.g. fishing gear) and offshore installations . Once in the oceans, they will either float at the ocean surface, or sink to the seafloor if made from polymers denser than seawater . Buoyant plastics may be cast ashore by inshore currents or winds , or may enter the open ocean, where they tend to accumulate in convergence zones such as the ones formed by the five large-scale gyres (South and North Pacific, South and North Atlantic, and Indian.