Environmental impact of open burning of polyester and cotton textile waste: a comparative analysis

Open burning of waste (OBW), particularly textile waste, is a growing but under-researched global issue with critical environmental and public health implications. This study examines the scale and impact of open burning of textile waste (OBTW), focusing on polyester and cotton materials commonly found in post-consumer and industrial waste streams. While high-income countries strictly regulate open burning, it remains prevalent in low- and middle-income countries due to limited waste infrastructure and poor waste management, contributing to severe air pollution and greenhouse gas (GHG) emissions. Our analysis estimates that between 10 and 20 Mt (medium 15 Mt) of textile waste is burned annually across 137 countries, with polyester burning alone contributing 8.3 to 24.6 Mt of fossil carbon dioxide (CO₂) emissions. The South Asia region accounts for 37% of these emissions, highlighting regional disparities in waste impacts. Open burning also releases hazardous pollutants such as particulate matter (PM_2.5, PM₁₀), polycyclic aromatic hydrocarbons (PAHs), and toxic heavy metals (THMs), disproportionately affecting vulnerable populations. Although natural fibers like cotton emit less CO₂, their combustion can still produce high levels of carbon monoxide (CO) under specific conditions. A sensitivity analysis shows that uncertainty in polyester emissions is driven mainly by the textile fraction in MSW and polyester emission factors, whereas uncertainty in cotton emissions is primarily influenced by the assumed cotton fiber share within the textile waste stream. This demonstrates that current emission inventories may misestimate impacts unless improved textile composition data and fiber-specific emission factors become available. This study underscores the urgent need for improved data, targeted research on pollutant behavior during textile combustion, and the development of waste management strategies to reduce the environmental and health burdens of open-burning practices.