Polystyrene contains the toxic substances Styrene and Benzene, suspected carcinogens, and neurotoxins that are hazardous to humans. Some estimates put the lifespan of styrofoam in a landfill around 500 years, and some put it way beyond that.
Most bean bags are filled with a manmade material known as expanded polystyrene (EPS). EPS is a hard-celled plastic very similar to Styrofoam, which is extruded polystyrene.
Besides bean bag beads, EPS is used for pop disposable coffee cups and as cushioning material for packaging and shipping.