Abstract
Accurate material flow models of plastic waste and recycling streams are crucial in intervening plastic waste’s negative environmental impact while enhancing circular lifestyles. Nairobi generates roughly 500 t of plastic waste daily, with about 70 % to 75 % collected by the responsible actors. 93 % of collections go to landfills with a small fraction recovered by informal waste pickers, collection or transfer stations and landfill scavengers. This study tracks importation, manufacturing, export, consumption, and disposal of PET (Polyethylene Terephthalate), HDPE (High Density Polyethylene), LDPE (Low Density Polyethylene), and PP (Polypropylene) plastics in Nairobi City applying Material Flow Analysis based on the mass balance model. Annually, approximately 385,000 t of plastics are imported into Nairobi for both B2B and B2C enterprises. Around 214,000 t of semi-refined materials move from one B2B to other B2B entities, and about 87,000 t to B2C companies, highlighting significant internal business dynamics. This novel study of interactions between B2B and B2C companies provides crucial insights into previously overlooked flows, enabling targeted policy interventions. Studying these dynamics is particularly important in growing economies like Nairobi, where rapid urbanization and economic expansion significantly influence plastic consumption and disposal patterns. Export activities including extra-boundary sales account for roughly 273,000 t annually, while local consumption reaches about 0.035 t per capita. Consumer-generated waste totals nearly 170,000 t annually, with a minimal fraction stored. Recyclers receive about 101,000 t annually, with an output efficiency of roughly 60 %, accumulating a stockpile of nearly 42,000 t. These figures indicate existing recycling infrastructure inefficiencies, underlining significant opportunities to enhance a circular economy. Policymakers can utilize these findings to strategically boost waste recovery efforts, optimize recycling operations, promoting sustainable plastic management.
