<p>System boundary diagram.</p>

Plastic waste poses significant environmental challenges in developing countries such as Ghana, where rapid economic growth, inadequate waste management infrastructure, and the persistence of linear production systems heighten the urgency of transitioning to circular, resource-efficient industrial pathways. This study evaluates the environmental impacts of manufacturing polyethylene carrier bags from recycled plastic waste in Ghana using the life cycle assessment (LCA) approach, in accordance with ISO 14040 and ISO 14044. The analysis considers 100,000 polyethylene carrier bags produced per year as the functional unit, with a total bag weight of 750 kg. The system boundary encompasses the manufacturing phase and includes the upstream environmental burdens of electricity consumption, sodium nitrate, and carbon black production, as captured in the Ecoinvent 3.11 database. Impact assessment was performed using SimaPro 10.2.0.3 and the ReCiPe 2016 Midpoint (H) V1.11/ World (2010) H methodology, covering 18 impact categories. Results showed that electricity consumption, sourced from Ghana’s fossil-intensive national grid (66.4% thermal, 32.9% hydropower, 0.7% renewables), is the dominant contributor to most impact categories, accounting for a global warming potential of 288.9 kg CO₂ eq (total GWP is 353.53 kg CO₂ eq), 137.2 kg 1,4-DCB eq (total is 264.5 kg 1,4-DCB eq) terrestrial ecotoxicity, and 106.3 kg oil eq (total is 131.3 kg oil eq) fossil resource scarcity. Sodium hydroxide, used in wastewater treatment, is the second-largest contributor to global warming (26.0 kg CO₂ eq). Carbon black is the second-largest contributor to fossil resource scarcity (13.7 kg oil eq), while sodium hydroxide and polyaluminium chloride used in wastewater treatment are significant contributors to toxicity categories. A sensitivity analysis comparing Ghana’s electricity grid to a solar tower energy scenario demonstrates that switching to renewable electricity reduces global warming potential by approximately 74%, from 353.5 kg CO₂ eq to 92.0 kg CO₂ eq, with similarly substantial reductions across most other impact categories. These findings underscore the critical role of energy decarbonization and additive optimization in improving the environmental performance of plastic recycling operations in Ghana and comparable sub-Saharan African contexts.