Environmental impacts and hazardous characteristics of LED lamps waste

Abstract

LED lighting technology has strongly taken the Thai lighting market due to the high consumption in residential, industrial and commercial sectors so the sustainability of LED lamps chain is considered as a critical factor for Thai lighting market. Additionally LED lamps waste consist of toxic metals hence improper landfilling has high potential to create negative environment and human health impact due to toxic metals contamination to environment. Therefore, this study focused on (1) quantifying environmental impact due to consumption behaviors among industrial lighting consumers and (2) hazard characterization and toxicity estimation of improper landfilling of LED lamps waste. Environmental impact due to the consumption of residential LED lamps for industrial purpose were compared by using Life Cycle Assessment (LCA) methodology via 6 scenarios based on possible lifespans and two energy mixes. Results identified that using residential LED models for industrial lighting purpose generates 25% greater impact in all six scenarios and human health impact is the highest contributing factor for endpoint indicators of all six scenarios.

In addition, toxic metal contents in LED lamp waste were examined by leaching process and compared with Thai and TTLC regulatory limits. Later the environmental and human toxicity impacts were investigated by applying USEtox model. From this study, the LED driver and source exhibited hazard characteristics under Thai regulations. Due to the presence of Copper (Cu), Lead (Pb), Zinc (Zn) and Silver (Ag) metals in exceeding concentrations compared to TTLC standard. For the environmental and human toxicity impacts, Aluminum (Al) leaching from LED driver showed the highest eco-toxicity level in all three compartments: soil, air, and water. The highest human toxicity impact from LED driver occurred due to Pb leaching to agricultural soil and air compartments. Only in water compartment, LED source was responsible for the human health toxicity impact from Zn leaching. Based on research findings, LED lamps consumption practices among industrial users and disposal options should be reevaluated for sustainable LED lighting applications in Thailand.