Low levels of residual oil fly ash (ROFA) impair innate immune response against environmental mycobacteria infection in vitro

► Air pollution provokes adverse health effects mainly on the respiratory system. ► Nowadays, urban pollution and mycobacteriosis produced by EM are emerging problems. ► We evaluated the effects of ROFA on the response to EM-infection on macrophages (AMs). ► ROFA altered AM response to EM by modifying the TNFα and superoxide anion production. ► ROFA reduced AM killing ability to EM and increased EM-infection susceptibility on AM.