Tracing the genealogy of the scientific claim that Indian lung capacity is deficient vis-à-vis the “European norm,” it is argued that the pathologisation of the Indian lung that once justified colonial-era segregation has made a troubling contemporary return, producing state imperceptibility of pollution-induced illness. Specifically, colonial theories of tropical air suggest that the Indian lung is uniquely suited to a dusty environment. When invoked in the present, this obviates the need for urgent pollution abatement action.