On February 14, 2022, María Del Camino Troya and co-authors from the Centre for Marine and Renewable Energy, University College Cork, Ireland published a perspective article in Frontiers in Marine Science in which they discuss loopholes in the EU Single Use Plastics Directive (SUP) around extruded versus expanded polystyrene (PS, CAS 9003-53-6). The SUP bans most uses of expanded PS but does not include restrictions on structurally similar extruded PS.
Both expanded and extruded PS “are rigid, closed cell foamed types of PS consisting of 98% air.” According to the authors, in Europe, most research either focuses solely on expanded PS or all PS-based materials together. “It is possible that the tendency to aggregate expanded PS and extruded PS data is driven by the presumption that results would apply to both styrenic polymers when placed under the same conditions, and may therefore not require independent studies. However, it would stand to reason that extruded PS would therefore, by association, have been included in the SUP Directive’s Annex of listed materials.” However, it is not.
Del Camino Troya et al. highlight several examples in Europe and the US that when expanded PS was banned for environmental and health effects, manufacturers and retailers switched to extruded PS. They suggest, “that a harmonization of terminology for foamed polystyrene which clearly differentiates between expanded and extruded PS should be adopted and supported to minimize confusion in regulatory, media, and academic environments.”
The International Agency for Research on Cancer (IARC) classifies styrene (CAS 100-42-5, the material from which PS is produced) as “probably carcinogenic to humans” and the US state of California includes styrene on its Proposition 65 list of carcinogens (FPF reported here and here). The European Commission (EC) is currently consulting on the use of styrene as a food contact material. Stakeholders can contribute to the survey until April 11, 2022.
Reference
Troya, M.D.C., et al. (2022). “Is It All About the Data? How Extruded Polystyrene Escaped Single-Use Plastic Directive Market Restrictions.” Frontiers in Marine Science. DOI: 10.3389/fmars.2021.817707
European Commission (February 2022). “Consultation: Survey on the use of styrene (FCM No. 193) in the manufacture of plastic and non-plastic food contact materials.”
