Editing Polystyrene (section)

===Production===
Polystyrene foams are produced using blowing agents that form bubbles and expand the foam. In expanded polystyrene, these are usually hydrocarbons such as [[pentane]], which may pose a flammability hazard in manufacturing or storage of newly manufactured material, but have relatively mild environmental impact.{{citation needed|date=June 2015}} Extruded polystyrene is usually made with [[hydrofluorocarbon]]s ([[HFC-134a]]),<ref>[http://www.earthresource.org/campaigns/capp/capp-styrofoam.html Polystyrene Foam Report] {{webarchive|url=https://web.archive.org/web/20130325091953/http://www.earthresource.org/campaigns/capp/capp-styrofoam.html |date=25 March 2013 }}. Earth Resource Foundation.</ref> which have global warming potentials of approximately 1000–1300 times that of carbon dioxide.<ref>[http://www.epa.gov/ozone/geninfo/gwps.html Global Warming Potentials of ODS Substitutes]. EPA.gov</ref> In Europe, where HFC-134a was banned since beginning 2022, XPS is produced using carbon dioxide as blowing agent, achieving an ODP (Ozone depletion potential) of 0 and a GWP (Global warming potential) below 5.Packaging, particularly expanded polystyrene, is a contributor of [[microplastics]] from both land and maritime activities.<ref>{{Cite web |last=Environment |first=U. N. |date=2021-10-21 |title=Drowning in Plastics – Marine Litter and Plastic Waste Vital Graphics |url=http://www.unep.org/resources/report/drowning-plastics-marine-litter-and-plastic-waste-vital-graphics |access-date=2022-03-21 |website=UNEP - UN Environment Programme |language=en}}</ref>