The world’s annual production of plastic materials has been steadily increasing over the past 20 years at a rate of nearly 5% production growth. In 2010, 265 million tonnes were produced, 6% (15 million) more than the previous year and consumption patterns show that within developing countries the increase of plastic consumption has been higher that the world average due to rapid urbanisation and economic development. This trend implies not only an increase in needed resources but higher quantities of plastic waste being generated.
In Asia and the Pacific region, plastic consumption has increased much more than the world average due to rapid urbanization and economic development. The consumerism has picked up sharply resulting in a rapid increase in plastic waste generation levels.
Most of the plastic waste generation is in cities. After food waste and paper waste, plastic waste is the major constituent of municipal waste and industrial waste in cities. Even the cities with low economic growth have started producing more plastic waste due to plastic packaging, plastic shopping bags, PET bottles and other goods/appliances using plastic as the major component (e.g. Dhaka produces about 140 tons of plastic waste every day). Figure 1 and 2 illustrate these findings.
ESP: Spain, GRC: Greece, HUN: Hungary, NDL: Netherlands, JPN: Japan
FRA: France, USA: United States of America
Figure 1: Increased Plastic Percentage within the Municipal Waste in selected OECD Countries
Figure 2: Plastic Waste Generation in 7 OECD Countries and in 7 Asian Cities
Due to the properties of the plastics, their high quantities being generated and the lack of efficient end of life management, in many developing countries plastics are now posing serious threats to the environment. Large amounts of waste plastics can be found as litter, spread within the cities, or are subject to treatments such as being burned, buried or open dumped; having all of these options detrimental consequences. Littered plastics, not only spoil the landscape but they block the sewage systems/drains, which contributes to floods, and also represent potential threats to wildlife when plastics are eaten as if they were food. On the other hand, the practice of burning plastics, along with other waste, releases toxic pollutants, which affects the quality of the air and poses negative impacts to public health.
Plastics disposed at the landfill, due to the high quantities generated and their non biodegradability (and therefore long life), require large spaces in the landfills and add pressure to space constrains. Additionally these plastics foster the formation of green house emissions (GHG) in the landfill by encapsulating organic materials under anaerobic conditions that will lead to the formation of methane.
Furthermore, even though recovery of plastics usually occurs within the informal sector, some types of plastic waste which in the past were being collected by waste reclaimers for recycling are nowadays being left in the trash since their lightweight nature make their collection not profitable (e.g. plastic containers or carrier bags).
These negatives impacts of waste plastics could be addressed or minimized through the recycling of plastic waste by which the plastics can be converted into a valuable resource. In this case, plastic recycling could contribute to:
Resource conservation, an important goal for most of the national and local governments, due to the current pressure on natural resources as a consequence of rapid industrialization and economic development.
GHG emission reduction potential on two accounts; (a) making fuel from waste plastic can obviate an equivalent amount of fossil fuels, (b) co-disposal of waste plastic in landfills causes formation of pockets of anaerobic decomposition of organic waste which can be avoided.
Plastic waste recycling, in most of the situations, could also be economically viable, as it generates resources which are in high demand however analysis of local conditions and consideration of the required initial capital investment are to be assessed.