Mercury Emission Dynamics in India: Insights from Sensitivity Analysis

India, as the second-largest global emitter of mercury, faces significant environmental challenges despite being a signatory to the Minamata Convention. Mercury’s toxic nature, coupled with its long-lasting presence and tendencies to bioaccumulate and biomagnify, underscores the urgency of monitoring its emissions and impacts. However, India lacks robust ground-based observation data to assess mercury's distribution and deposition comprehensively. In this study, we utilized the GEOS-Chem model with the latest inventory available at 0.25° × 0.3125° to simulate mercury dynamics over India (2015 to 2017). The results reveal that regions hosting coal-based thermal power plants and brick kilns exhibit the highest mercury deposition (100-140 µg m^-2 a^-1) and atmospheric concentrations (10-20 ng m^-3). Sensitivity analyses further delineated the contributions of natural and Indian anthropogenic emissions to mercury deposition across India and Asia. Additionally, we evaluate the impact of Asian emissions on India’s mercury burden. This study provides insights into the spatial dynamics of mercury in India and highlights the regional interdependence of emissions. These findings can guide policymakers in formulating targeted mitigation strategies to reduce mercury emissions and their transboundary impacts effectively. Further research is needed to examine the transformation of deposited mercury into its bioaccumulative form, methylmercury, and its implications for human health.