text:  RPMI 2650 cells exposed to particle-free clean air 6h replicate 2 RPMI 2650 cells exposed to particle-free clean air for 6h with 0h post-exposure incubation cell line: ATCC #CCL-30 RPMI 2650; cell type: nasal septal squamous cell carcinoma cell line; treatment: exposed to clean air 6h