Environmental Research Letters
Published 25 August 2020
https://iopscience.iop.org/article/10.1088/1748-9326/ab9e1e

Martin C Heller $^1$ , Michael H Mazor $^1$ and Gregory A Keoleian $^1$
$^1$ Center for Sustainable Systems, School for Environment and Sustainability, University of Michigan, 3012 Dana Building, 440 Church Street, Ann Arbor, Michigan 48109-1041 United States of America

Abstract

The first contemporary plastics material flow by resin type through the US economy (2017 production, sales, use markets and end-of-life management).

2. Methods

2.1. Plastics manufacture, trade and use by market sectors

• The starting point is the survey-based industry data compiled for the American Chemistry Council (ACC), covering 95% - 100% of the total US production for the materials reported.
• Reported exports represent sales by resin manufacturers to foreign buyers, but do not capture additional exports by brokers or other third party sales.
• We include US imports of primary form plastics as well as formed plastics (rods, sticks, sheets, films, plates, caps, etc) based on US trade data for 2017.
• The plastics contained in imported finished goods (foods, apparel, footwear, computers and electronics, appliances, automobiles, furniture, medical supplies, athletic goods, toys) and their packaging were estimated using the monetary value of net imports into the US, averaged over three years (2016–2018) combined with sector-level estimates of plastic content per unit of revenue .

2.2. Plastics in municipal solid waste

• The US EPA maintains national level data of municipal solid waste(MSW) in the US, using to define the post-use flow of plastics.
• In the US EPA method, containers and packaging are assumed to be discarded in the same year that the products they contain are purchased.
• Disposal of non-durable goods(last less than three years) and durable goods(over three years) reported as data of previous years of 2017.

2.3. Disposition of plastics in MSW

• The End of life (EOL) disposition of plastics contained in MSW is informed by data from US EPA.
• Recovery of plastics in US EPA is also primarily based on industry-sourced surveys.
• After recovery, disposal of plastics in MSW is distributed between combustion with energy recovery and landfill based on average national rates.

2.4. Additional waste streams

• Construction and demolition(C&D) waste and automotive shredder residue(ASR) are estimated according to <2% of total C&D generation in the US and the number of end of life vehicles disposed annually in the US (with plastics content in 2003). Packaging materials of the former is recycled by the C&D recyclers and the landfill disposal is assumed for the latter.

3. Results and discussion

• Figure 1 represents our best understanding of the material flow of plastics in the US circa the year 2017, based on available data.