Cinnamon-flavored e-liquids significantly ↓ phagocytic activity of both alveolar macrophages and neutrophils and suppressed NK cells' ability to eliminate target leukemia cells. ↑ IL-6 in macrophages, ↑ IL-8 production, and enhanced NET formation (anti-bacterial function) in neutrophils. Restoration of phagocytic activity of macrophages with small-molecule reducing agent 1,4-dithiothreitol. Cinnamaldehyde-flavored VEC did not significantly alter neutrophil phagocytosis compared to the unheated e-liquids. Here, CXCL8 is linked to leukemia.