The roles of informal plastic packaging waste recycling pathways in a large metropolitan region

In many large metropolitan regions in developing countries plastic packaging waste (PPW) management services remain insufficient, limiting the recirculation of materials, and much of the gap is filled by the informal sector. This study investigates informal PPW recycling pathways using mass flow analysis in the city of Lima, Peru. Primary data were collected between 2024 and 2025 through household surveys (n = 418), an exploratory waste audit (n = 21), and semi-structured interviews (n=127) with key stakeholders. Average household PPW generation is 12.8 kg/yr per capita, with plastic bags accounting for almost one third of the total PPW. Household separation averages 37.9% of all PPW generation, yet more than half (58.7%) of the separated PPW is disposed of informally. At the collection stage, most waste is recovered through informal pathways, and this dominance increases at the aggregation stage. Recycling rates differ strongly by material type, with high recovery for PET, moderate for rigid plastics, and very limited for flexibles, reflecting economic selectivity in recycling. These findings reveal that informal collection and aggregation are responsible for most recovered materials, acting as a key functional part of PPW recycling in Lima despite limited formal services. PPW management in Lima operates as a hybrid formal–informal system, where household practices, material value, and limited service coverage jointly determine recovery outcomes, shaping the extent to which materials can be retained within a circular economy.