Ending Plastic Permanence through Sandhi

Plastic pollution is commonly framed as a toxicity or recycling-efficiency problem, yet its true hazard lies in persistence. Plastic is feared because it does not end. When recycling systems tolerate reversible intermediate states, waste accumulates as instability, economic loss, and environmental risk. Ending plastic permanence—not optimizing gradual degradation—is therefore the core challenge in sustainable waste management. This paper introduces Sandhi, a system-level control principle that enforces irreversible identity collapse in plastic waste processing. By defining a testable irreversibility threshold, implementing conservative sensing, and recirculating any reversible material, Sandhi stabilizes conversion and improves energy recovery for dry mixed waste streams. Rather than proposing new chemistry, the framework reframes plastic recycling as a problem of controlled irreversibility, offering a practical and experimentally verifiable pathway to scalable plastic waste resolution. We fear plastic because it never ends. End it — and the fear disappears.