<p>This study investigates the impact of the COVID-19 lockdown on the dynamic behavior of atmospheric pollutants in the Caribbean using multifractal analysis techniques. Statistical analyses first revealed a marked decrease in nitrogen oxide concentrations, attributable to the sharp reduction in anthropogenic activity in 2020. However, contrary to global trends reported in numerous studies, PM₁₀ levels increased during the lockdown period, while ozone concentrations exhibited an unexpected decline. This increase is mainly attributed to the dominance of natural sources such as Saharan dust and marine aerosols, which are largely unaffected by reductions in local anthropogenic activities. Then, the Multifractal Detrended Fluctuation Analysis (MFDFA) highlighted notable changes in nitrogen oxide dynamics. During the reference period (2018-2019), NO exhibited persistent multifractal behavior, while NO₂ was monofractal and persistent. In 2020, under lockdown conditions, NO fluctuations became nearly uncorrelated, and NO₂ developed multifractal characteristics. These results suggest a disruption in emission patterns due to reduced anthropogenic activity. In contrast, ozone and PM₁₀ did not show significant changes, indicating that their dynamics are less influenced by local emissions. Ozone remained persistent, consistent with its long atmospheric lifetime, and PM₁₀ showed no clear scaling properties, likely due to dominant natural sources such as sea spray and Saharan dust. Multifractal Analysis based on the Partition Function (MFPF) identified two scale-dependent regimes in nitrogen oxide time series: a medium-scale regime with strong multifractality and a large-scale regime with lower multifractality. At medium scales, changes in the degree and symmetry of multifractality were evident during the lockdown. At large scales, a rightward asymmetry emerged in NO₂ and NO_x, reflecting a dominance of low concentrations. These findings underscore the sensitivity of nitrogen oxides to short-term human activity.</p>