Unregulated Dust: The Impact of Excavation on Urban Air Quality and Vulnerable Communities in the Global South

Urban excavation activities are a major yet underregulated source of particulate and gaseous emissions in rapidly developing economies. This systematic review examines excavation-related air pollutants—PM2.5, PM10, NOx, and CO—through quantitative synthesis of emission factors, regulatory standards, and mitigation measures. Following a PRISMA-guided protocol, 60 peer-reviewed studies were screened, with inclusion criteria emphasizing urban contexts in the Global South. Results indicate that excavation phases can generate PM2.5 and PM10 concentrations up to 20 times higher than WHO limits, with localized spikes persisting for hours. Comparisons across Delhi, Belgrade, and Kanpur reveal variations linked to machinery age, fuel type, and enforcement rigor. Case analyses show that strict regulatory frameworks, such as Hong Kong’s NRMM controls, achieve measurable pollutant reductions, while technically ambitious but weakly enforced policies underperform. Engineering interventions, including water mist cannons, soil binders, wheel-wash facilities, and negative-pressure enclosures, demonstrate reductions in particulate loads ranging from 50% to over 90% when properly deployed. However, coverage is inconsistent, and real-time monitoring systems remain underutilized. A significant environmental justice gap is evident, with low-income and informal communities disproportionately exposed. The study recommends targeted excavation-specific regulations, integration of continuous monitoring with automated enforcement, and energy-efficient dust suppression technologies to minimize both air quality and carbon impacts. By framing excavation emissions as both an environmental and social equity challenge, this research underscores the urgency of embedding excavation-specific measures into urban air quality management in developing economies.