Sustainable Urban Development: A Particulate Matter 2.5 Moss Mitigation System for Air Pollution Control in Kuala Lumpur, Malaysia

Abstract

Fine particulate matter 2.5 (PM2.5) poses a significant public health concern in rapidly urbanising cities such as Kuala Lumpur, Malaysia, where concentrations often exceed international air quality guidelines. This study evaluates the feasibility and effectiveness of a moss-based PM2.5 mitigation system using Leucobryum glaucum as a natural biofilter. A controlled mesocosm experiment was conducted to simulate urban pollution conditions, with PM2.5 generated through a controlled combustion source in a sealed chamber and monitored over a 120-minute exposure period. Baseline trials without moss were compared against treatments incorporating moss covering a surface area of 234cm2. The presence of moss resulted in a substantial reduction in PM2.5 concentrations, with weighted mean values decreasing from 806.5 μg m−3 to 281.5 μg m−3 and an average absorption rate of 4.29 μg m−3 min−1, corresponding to an estimated removal efficiency of approximately 65%. Extrapolation of these findings suggests that moss-based installations could meaningfully reduce local PM2.5 levels in high-traffic urban environments. The results indicate that moss-based systems represent a promising, low-cost, and environmentally sustainable nature-based solution for urban air pollution mitigation, with potential applications in urban planning and green infrastructure strategies.