Spiers Memorial Lecture: Compostable plastics: promise and pitfalls

Plastics have enabled modern innovations through their unique attributes, which include a combination of light weight, durability, and cost-effectiveness. These characteristics, while central to their utility, have paradoxically contributed to the escalating plastic pollution crisis. No single approach can resolve this challenge; rather, it requires coordinated efforts with a diversity of strategies. Among them, compostable plastics have emerged as a particularly promising avenue. Under controlled conditions, such ephemeral plastics can degrade and transform into compost, offering environmental benefits that extend to soil, water, and agriculture. Nevertheless, substantial challenges remain before compostable plastics can achieve broad adoption and deliver their full promise. In this perspective, we (i) make the case for more widespread use of compostable plastics in the food packaging market, (ii) review labeling, infrastructure, and regulatory hurdles facing compostable-plastic adoption, and (iii) discuss the future of compostable-polymer research and development.