Vol. 8, Special Issue 9 (2025)
Abstract
End-of-life tyres (ELTs) management is a growing environmental problem globally, caused by their complex material contents, non-biodegradable nature, and increasing abundance. Recycling, retreading, and energy recovery as sustainable management methods are promoted, yet a significant proportion of used tyres end up in landfills. This review examines environmental impacts of tyre rubber waste in landfill environments, considering in particular soil, ground, and atmospheric contamination, together with associated ecological and health risk consequences. Tyres are a combination of natural and synthetic rubber, carbon black, steel, various fibres, and an array of chemical additives that include heavy elements and organic chemicals. When disposed of in landfills, such wastes decompose slowly, providing leachates that are composed of extremely high levels of zinc, lead, cadmium, and other toxic materials that could be washed into nearby soil and groundwater. Further, tiny tyre pieces could contaminate soil and disrupt microbial communities, along with leachate flow, which could destroy nearby bodies of water. Another glaring fact is that tyres are a fire hazard when tyres are burned in a pile or buried as they lead to emission of toxic gases such as dioxins, furans, and volatile organic chemicals, causing air pollution as well as altering climate. Apart from devastating the environment, these pollutants directly and indirectly affect the health of people. They do so by polluting groundwater and by human beings inhaling dangerous smoke from burnt tyres. The current methods of managing such pollutants, such as unique landfill constructions and incorporation of tyre shredding in construction work, reduce it somewhat, yet don't eliminate the ultimate threat. This review suggests a need of better regulatory body for surveillance of landfill leachate, and adoption of circular economy strategies to reduce accumulation of tyres in landfill areas. The study is however unclear, specifically in regard to fates of micro-rubbers in soil as well as environmental outcomes from leachate transit through soil. More research targeting such knowledge gaps is a move towards sustainable approaches to tyre rubber waste management.
