During the period 1950-2015, the group estimated that we have generated 8.3 Gt of plastics, 6.3 Gt of which has already become waste. Of that waste total, only 9% was recycled, 12% incinerated and 79% accumulated in landfills or the natural environment. The study predicts that, if current trends continue, this latter proportion will weigh 12 Gt by 2050. Global production of plastics was calculated to have increased from 2 Mt in 1950 to over 400 Mt in 2015, outgrowing most other human-made materials.
The scientists compiled production statistics for resins, fibres and additives from a variety of industry sources and synthesised them according to type and consuming sector.
The largest groups in total nonfibre plastics production were PE (36%), PP (21%), and PVC (12%), followed by PET, PUR, and PS (<10% each). Polyester, most of which is PET, accounted for 70% of all polyester, polyamide and acrylic fibre production. These groups together were found to account for 92% of all plastics ever made.
Approximately 42% of all nonfibre plastics were found to have been used for packaging, which was the largest plastics market – and usually results in single-use applications that are rapidly discarded.
Lead author of the paper Roland Geyer said: “Half of all plastics become waste after four or fewer years of use.” He added: “What we are trying to do is to create the foundation for sustainable materials management. Put simply, you can't manage what you don't measure, and so we think policy discussions will be more informed and fact based now that we have these numbers.”
Co-author Kara Lavender Law added: “There are areas where plastics are indispensable, especially in products designed for durability. But I think we need to take a careful look at our expansive use of plastics and ask when the use of these materials does or does not make sense.”
Science Advances: http://doi.org/b9sp