Polystyrene (PS)

Polystyrene (PS) is a petroleum-based synthetic polymer made from styrene monomers, creating either rigid plastic or expanded foam (commonly known as Styrofoam). Polystyrene comes in two main forms: solid polystyrene (used for disposable cutlery and plastic cups) and expanded polystyrene foam/EPS (used for takeout containers, coffee cups, packing materials, coolers). PS is valued for its low cost, lightweight, insulating properties (foam), and ease of molding. However, polystyrene is one of the most problematic plastics from both health and environmental perspectives, leaches styrene (a human carcinogen), breaks apart easily into microplastics and is virtually impossible to recycle (less than 1% is recycled), is banned in many cities worldwide, and persists in the environment for 500+ years while causing significant harm to marine ecosystems.

For those seeking plastic-free living, polystyrene should be avoided by opting for plastic-free alternatives.

Food Service (Foam EPS): Takeout containers, coffee cups, plates, bowls, clamshell containers, soup cups

Packaging Materials: Foam peanuts, protective foam inserts, electronics packaging, foam blocks

Grocery Packaging: Meat trays, produce trays, egg cartons, bakery containers

Disposable Items: Cutlery (forks, spoons, knives), clear plastic cups, plastic plates

Coolers & Insulation: Foam coolers, ice chests, insulation boards, foam panels

Microplastic Concerns: Polystyrene is one of the worst plastics for microplastic pollution and exposure. PS foam takeout containers crumble when handled, while hot liquids and acidic foods only cause the material to break down faster, releasing even more microplastics. The foam structure ensures PS never fully breaks down, only fragmenting into smaller pieces indefinitely.

Chemical Safety: Outside of microplastic shedding, polystyrene's primary health concern is the leaching of styrene, a human carcinogen. Styrene exposure is linked to: increased cancer risk (leukemia, lymphoma), reproductive effects, developmental issues, neurological effects (headaches, fatigue, dizziness), hormone disruption. The most common use case of polystyrene - hot coffee or tea foam cups - shed additional styrene from the exposure to hot liquids.