This story was originally published by Grist. Sign up for Grist’s weekly newsletter here. If you were to create a recipe for plastics, you’d need a very big cookbook. In addition to fossil fuel-based building blocks like ethylene and propylene, this ubiquitous material is made from a dizzying amalgam of more than 16,000 chemicals—colorants, flame retardants, stabilizers, lubricants, plasticizers, and other substances, many of whose exact functions, structures, and toxicity are poorly understood.
These pebble-sized pieces often spill directly from factories or during transportation, and can release their chemicals once in the environment. At the end of the plastic life cycle, incinerators and landfills can release PFAS, dioxins, PCBs, and other endocrine disruptors as air or soil pollution—some of which may contaminate nearby food supplies.